JP4805730B2

JP4805730B2 - Evaluation method, evaluation program, and evaluation apparatus

Info

Publication number: JP4805730B2
Application number: JP2006157146A
Authority: JP
Inventors: 健二野村
Original assignee: Fujitsu Ltd
Current assignee: Fujitsu Ltd
Priority date: 2006-06-06
Filing date: 2006-06-06
Publication date: 2011-11-02
Anticipated expiration: 2026-06-06
Also published as: JP2007327767A

Description

本発明は評価方法、評価プログラムおよび評価装置に関し、特に、強誘電体の分極を評価する評価方法、評価プログラムおよび評価装置に関する。 The present invention relates to an evaluation method, an evaluation program, and an evaluation apparatus, and more particularly, to an evaluation method, an evaluation program, and an evaluation apparatus for evaluating the polarization of a ferroelectric substance.

近年、半導体装置を構成する素子の材料として、チタン酸ジルコン酸鉛（Ｐｂ（Ｚｒ_1-xＴｉ_x）Ｏ₃）をはじめとする強誘電体材料が注目されている。また、すでにそのような強誘電体をキャパシタ材料として用いた強誘電体メモリ（Ferroelectric Random Access Memory，ＦｅＲＡＭ）が実用化されている。ＦｅＲＡＭに強誘電体からなる膜を用いた場合には、その膜の分極の極性および大きさが、ＦｅＲＡＭ特性に大きく影響してくる。 In recent years, ferroelectric materials such as lead zirconate titanate (Pb (Zr _1-x Ti _x ) O ₃ ) have attracted attention as materials for elements constituting semiconductor devices. In addition, a ferroelectric memory (Ferroelectric Random Access Memory, FeRAM) using such a ferroelectric as a capacitor material has already been put into practical use. When a film made of a ferroelectric material is used for FeRAM, the polarity and magnitude of polarization of the film greatly influence the FeRAM characteristics.

従来、強誘電体の分極を評価する方法としては、走査型プローブ顕微鏡（Scanning Probe Microscope，ＳＰＭ）を用いてその極性および大きさを評価する方法が提案されている（特許文献１参照）。このほか、強誘電体の分極を評価する方法として、試料の温度を変化させて表面電荷の極性を評価する方法も提案されている（特許文献２参照）。なお、この提案では、試料に光を照射し、分域壁における消光比の劣化によって極性を評価する方法についても述べられている。 Conventionally, as a method for evaluating the polarization of a ferroelectric material, a method of evaluating the polarity and size using a scanning probe microscope (SPM) has been proposed (see Patent Document 1). In addition, as a method for evaluating the polarization of the ferroelectric, a method for evaluating the polarity of the surface charge by changing the temperature of the sample has been proposed (see Patent Document 2). This proposal also describes a method for evaluating the polarity by irradiating the sample with light and degrading the extinction ratio in the domain wall.

また、従来、Ｘ線を用いて強誘電体の分極を評価する方法も提案されている（特許文献３参照）。この提案では、Ｘ線回折による回折ピークが分裂しているか否かに応じ、分裂している場合にはその回折ピーク位置を基に、分裂していない場合には所定の回折線の半値幅を基に、それぞれ分極の大きさを算出するようにしている。また、このようなＸ線のほか、強誘電体にアルゴンレーザ等を照射し、そのときその強誘電体から放射されるラマン散乱光を検出することによって、その強誘電体の分極の大きさを評価するといった方法も提案されている（特許文献４参照）。
特開２００２−３２３５４３号公報特開平９−４９８１３号公報特開２００２−１８１７３９号公報特開２０００−６８４６４号公報 Conventionally, a method for evaluating the polarization of a ferroelectric using X-rays has also been proposed (see Patent Document 3). In this proposal, depending on whether or not the diffraction peak by X-ray diffraction is split, the half-width of a predetermined diffraction line is set based on the position of the diffraction peak when splitting, or when not splitting. Based on this, the magnitude of polarization is calculated. In addition to such X-rays, the ferroelectric material is irradiated with an argon laser or the like, and the Raman scattered light emitted from the ferroelectric material is detected at that time, whereby the magnitude of polarization of the ferroelectric material is determined. An evaluation method has also been proposed (see Patent Document 4).
JP 2002-323543 A Japanese Patent Laid-Open No. 9-49813 JP 2002-181739 A JP 2000-68464 A

しかし、強誘電体の分極を評価するための従来の方法には、以下のような問題点があった。
まず、強誘電体の分極の極性および大きさをＳＰＭによって評価する場合には、評価に当たり、収束イオンビーム（Focused Ion Beam，ＦＩＢ）等による試料の加工が必要になり、その試料を破壊してしまうことになる。そのため、ＳＰＭは、完成前あるいは完成後の製品についての不良解析には用いることができても、最終的に製品の良・不良を判定する際のような非破壊で行われるべき検査には用いることができない。 However, the conventional method for evaluating the polarization of the ferroelectric has the following problems.
First, when the polarity and magnitude of the polarization of the ferroelectric material are evaluated by SPM, the sample needs to be processed by a focused ion beam (FIB) or the like for the evaluation, and the sample is destroyed. Will end up. Therefore, SPM can be used for failure analysis of products before or after completion, but it is used for inspections that should be performed non-destructively, such as when determining the quality of products. I can't.

また、試料の温度を変化させて表面電荷の極性を評価する方法は、電極を形成して強誘電体キャパシタとした状態では評価することができない。また、この方法の場合、温度変化による試料の変質の懸念もある。 Further, the method of evaluating the polarity of the surface charge by changing the temperature of the sample cannot be evaluated in the state where the electrode is formed to form a ferroelectric capacitor. In the case of this method, there is a concern that the sample may be deteriorated due to a temperature change.

試料に光を照射し分域壁における消光比の劣化によって極性を評価する方法、あるいは光を照射しラマン散乱光を検出して分極の大きさを評価する方法の場合でも、やはり強誘電体キャパシタとした状態では評価することができない。 Even in the case of the method of irradiating the sample with light and evaluating the polarity by the deterioration of the extinction ratio in the domain wall, or the method of irradiating the light and detecting Raman scattered light to evaluate the magnitude of polarization, the ferroelectric capacitor is still used. It cannot be evaluated in the state.

したがって、これらの方法では、ＦｅＲＡＭの製造過程、すなわち強誘電体の成膜からメモリの完成（パッケージ封止後）にわたって、強誘電体を非破壊・非接触で評価することができなかった。 Therefore, in these methods, the ferroelectric could not be evaluated in a non-destructive and non-contact manner during the FeRAM manufacturing process, that is, from the ferroelectric film formation to the completion of the memory (after packaging).

メモリの完成までの強誘電体の評価を非破壊・非接触で行うことのできる方法として、上記のようなＸ線回折ピークの位置や形状（分裂状態）を基に評価する方法がある。しかし、この方法では、強誘電体の分極の大きさを知ることはできても、その分極の極性を判別することはできなかった。 As a method capable of performing non-destructive and non-contact evaluation of the ferroelectric material until the completion of the memory, there is a method of evaluating based on the position and shape (split state) of the X-ray diffraction peak as described above. However, with this method, although the magnitude of the polarization of the ferroelectric material can be known, the polarity of the polarization cannot be determined.

本発明はこのような点に鑑みてなされたものであり、Ｘ線を用いて強誘電体の分極の極性を判別することのできる評価方法、評価プログラムおよび評価装置を提供することを目的とする。 The present invention has been made in view of these points, and an object thereof is to provide an evaluation method, an evaluation program, and an evaluation apparatus that can determine the polarity of polarization of a ferroelectric substance using X-rays. .

本発明の一観点によれば、強誘電体を構成する元素の吸収端近傍のエネルギーを有するＸ線であって、前記強誘電体の分極の極性によって前記強誘電体の分極方向と直交しない方位の回折ピーク強度が異なるエネルギーを有する前記Ｘ線を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定し、前記Ｘ線が有するエネルギーとの間に前記吸収端が含まれるようなエネルギーを有する他のＸ線を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定し、前記Ｘ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記他のＸ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度とを用いて前記強誘電体の分極の極性を判別する評価方法が提供される。 According to one aspect of the present invention , X-rays having energy in the vicinity of the absorption edge of an element constituting a ferroelectric material, the orientation not being orthogonal to the polarization direction of the ferroelectric material due to the polarity of polarization of the ferroelectric material Using the X-rays with different diffraction peak intensities, the diffraction peak intensities in directions not perpendicular to the polarization direction of the ferroelectric are measured, and the absorption edge is between the energy of the X-rays. Using other X-rays having energy as contained, the diffraction peak intensity in an orientation not orthogonal to the polarization direction of the ferroelectric is measured, and the ferroelectric of the ferroelectric measured using the X-ray is measured. The diffraction peak intensity in an orientation not orthogonal to the polarization direction and the diffraction peak intensity in an orientation not orthogonal to the polarization direction of the ferroelectric measured using the other X-rays are used to determine the polarization of the ferroelectric. Polarity Another to that evaluation method is provided.

このような評価方法によれば、強誘電体の分極方向と直交しない方位の回折ピーク強度が、その強誘電体を構成する元素の吸収端近傍のエネルギーを有しその強誘電体の分極の極性によって分極方向と直交しない方位の回折ピーク強度が異なるエネルギーを有するＸ線を用いて測定され、測定されたその回折ピーク強度を用いてその強誘電体の分極の極性が判別される。これにより、Ｘ線を用いて強誘電体の分極の極性が評価されるようになる。 According to such an evaluation method, the diffraction peak intensity in an orientation not orthogonal to the polarization direction of the ferroelectric has energy near the absorption edge of the element constituting the ferroelectric, and the polarity of polarization of the ferroelectric The diffraction peak intensity in an orientation not orthogonal to the polarization direction is measured using X-rays having different energies, and the polarity of polarization of the ferroelectric is determined using the measured diffraction peak intensity. Thereby, the polarity of polarization of the ferroelectric is evaluated using X-rays.

また、本発明の一観点によれば、コンピュータを、Ｘ線回折装置に、強誘電体を構成する元素の吸収端近傍のエネルギーを有するＸ線であって、前記強誘電体の分極の極性によって前記強誘電体の分極方向と直交しない方位の回折ピーク強度が異なるエネルギーを有する前記Ｘ線を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定させる手段、前記Ｘ線回折装置に、前記Ｘ線が有するエネルギーとの間に前記吸収端が含まれるようなエネルギーを有する他のＸ線を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定させる手段、前記Ｘ線回折装置によって前記Ｘ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記Ｘ線回折装置によって前記他のＸ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度とを用いて前記強誘電体の分極の極性を判別する手段、として機能させる評価プログラムが提供される。 According to an aspect of the present invention, the computer, the X-ray diffraction apparatus, an X-ray having an energy of the absorption edge near the elements constituting the ferroelectric, the polarity of the polarization of the ferroelectric Means for measuring a diffraction peak intensity of an orientation not orthogonal to the polarization direction of the ferroelectric using the X-rays having energy different in diffraction peak intensity of an orientation not orthogonal to the polarization direction of the ferroelectric; X Using another X-ray having an energy such that the absorption edge is included between the X-ray and the energy of the X-ray, the diffraction peak intensity in an orientation not orthogonal to the polarization direction of the ferroelectric means for measuring a diffraction peak intensity of the bearing by the X-ray diffraction apparatus is not orthogonal to the polarization direction of the ferroelectric measured using the X-ray before by the X-ray diffraction apparatus The ferroelectric said means for determining the polarity of the polarization of the ferroelectric by using the diffraction peak intensity of orientation that is not orthogonal to the polarization direction, evaluation program Ru to function as a measured using other X-ray Is provided.

このような評価プログラムによれば、コンピュータが、Ｘ線回折装置に所定エネルギーのＸ線を用いて強誘電体の分極方向と直交しない方位の回折ピーク強度を測定させる手段、測定されたその回折ピーク強度を用いてその強誘電体の分極の極性を判別する手段として機能する。これにより、コンピュータおよびＸ線回折装置によって、Ｘ線を用いた強誘電体の分極の極性の評価が行われるようになる。 According to such an evaluation program, the computer causes the X-ray diffractometer to measure the diffraction peak intensity in an orientation not orthogonal to the polarization direction of the ferroelectric substance using X-rays having a predetermined energy, and the measured diffraction peak. It functions as a means for discriminating the polarity of polarization of the ferroelectric substance using the intensity. Thereby, the polarity of the polarization of the ferroelectric using X-rays is evaluated by the computer and the X-ray diffractometer.

また、本発明の一観点によれば、強誘電体を構成する元素の吸収端近傍のエネルギーを有するＸ線であって、前記強誘電体の分極の極性によって前記強誘電体の分極方向と直交しない方位の回折ピーク強度が異なるエネルギーを有する前記Ｘ線を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定する手段と、前記Ｘ線が有するエネルギーとの間に前記吸収端が含まれるようなエネルギーを有する他のＸ線を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定する手段と、前記Ｘ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記他のＸ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度とを用いて前記強誘電体の分極の極性を判別する手段と、を有する評価装置が提供される。 According to another aspect of the present invention , X-rays having energy in the vicinity of an absorption edge of an element constituting a ferroelectric material, and orthogonal to the polarization direction of the ferroelectric material depending on the polarization polarity of the ferroelectric material. diffraction peak intensity of the bearing does not have by using the X-rays having different energies, means for measuring the diffraction peak intensity of orientation that is not orthogonal to the polarization direction of the ferroelectric, between the energy which the X-ray has Using other X-rays having such energy that the absorption edge is included, the diffraction peak intensity of an orientation not perpendicular to the polarization direction of the ferroelectric is measured using the X-rays . wherein using the diffraction peak intensity of orientation that is not orthogonal to the polarization direction of the ferroelectric, and a diffraction peak intensity of orientation that is not orthogonal to the polarization direction of the measured the ferroelectric using the other X-ray It means for discriminating the polarity of the polarization of the dielectric, the evaluation apparatus that have a are provided.

このような評価装置によれば、所定エネルギーのＸ線を用いて強誘電体の分極方向と直交しない方位の回折ピーク強度が測定され、測定されたその回折ピーク強度を用いてその強誘電体の分極の極性が判別される。これにより、Ｘ線を用いて強誘電体の分極の極性が評価されるようになる。 According to such an evaluation apparatus, the diffraction peak intensity in an orientation not orthogonal to the polarization direction of the ferroelectric is measured using X-rays of a predetermined energy, and the ferroelectric peak is measured using the measured diffraction peak intensity. Polarization polarity is determined. Thereby, the polarity of polarization of the ferroelectric is evaluated using X-rays.

強誘電体の構成元素の吸収端近傍でその強誘電体の分極の極性によって回折ピーク強度が異なるエネルギーを有するＸ線を用いて回折ピーク強度を測定し、測定されたその回折ピーク強度を用いてその強誘電体の分極の極性を判別する。これにより、強誘電体の分極の極性を、Ｘ線を用いて非破壊・非接触で評価することができると共に、その分極の極性を適正にかつ簡便に評価することができる。
A diffraction peak intensity is measured near the absorption edge of the constituent element of the ferroelectric using X-rays having an energy whose diffraction peak intensity differs depending on the polarization polarity of the ferroelectric, and the measured diffraction peak intensity is used. It determines the polarity of the polarization of the ferroelectric. Thereby, the polarity of the polarization of the ferroelectric can be evaluated non-destructively and non-contactly using X-rays, and the polarity of the polarization can be evaluated appropriately and simply.

以下、本発明の実施の形態を、図面を参照して詳細に説明する。
まず、第１の実施の形態について説明する。
図１は評価試料の断面模式図である。 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, the first embodiment will be described.
FIG. 1 is a schematic cross-sectional view of an evaluation sample.

図１に示す評価試料は、シリコン（Ｓｉ）基板１０上に酸化シリコン（ＳｉＯ₂）膜１１が形成され、その上に下地層として酸化アルミニウム（Ａｌ₂Ｏ₃）膜１２、下部電極として白金（Ｐｔ）膜１３、強誘電体膜としてＰｂ（Ｚｒ_0.5Ｔｉ_0.5）Ｏ₃（ＰＺＴ）膜１４、および上部電極として酸化イリジウム（ＩｒＯ₂）膜１５を順に積層した構造を有している。ＰＺＴ膜１４は、膜厚が約１５０ｎｍ、正方晶構造であって、その分極方向は（００１）であるものとする。 In the evaluation sample shown in FIG. 1, a silicon oxide (SiO ₂ ) film 11 is formed on a silicon (Si) substrate 10, an aluminum oxide (Al ₂ O ₃ ) film 12 is formed thereon as a base layer, and platinum ( A Pt) film 13, a Pb (Zr _0.5 Ti _0.5 ) O ₃ (PZT) film 14 as a ferroelectric film, and an iridium oxide (IrO ₂ ) film 15 as an upper electrode are sequentially stacked. The PZT film 14 has a film thickness of about 150 nm and a tetragonal structure, and its polarization direction is (001).

ここで、このような構造を有する評価試料であって、そのＰＺＴ膜１４の分極が上向き、下向きであることがわかっているものについてそれぞれ、ＰＺＴ膜１４の構成元素の１つであるジルコニウム（Ｚｒ）の吸収端近傍のエネルギーを有するＸ線を用いて、Ｘ線回折装置を用いて回折測定を行い、その分極方向と同じ方位の（００６）の回折ピークの積分強度（回折ピーク強度）を求めた。 Here, each of the evaluation samples having such a structure, in which the polarization of the PZT film 14 is known to be upward and downward, is respectively zirconium (Zr) which is one of the constituent elements of the PZT film 14. ) Is measured using an X-ray diffractometer using X-rays having energy near the absorption edge, and the integrated intensity (diffraction peak intensity) of the (006) diffraction peak in the same orientation as the polarization direction is obtained. It was.

図２および図３はＸ線のエネルギーと回折ピーク強度の関係を示す図である。図２において、横軸はＸ線のエネルギー（ｋｅＶ）を表し、縦軸は（００６）の回折ピーク強度Ｉ（００６）を表している。なお、図２中、分極が上向きのときの（００６）の回折ピーク強度はＩ↑（００６）、分極が下向きのときの（００６）の回折ピーク強度はＩ↓（００６）と示している。また、図３において、横軸はＸ線のエネルギー（ｋｅＶ）を表し、縦軸は図２に示した分極が上向きのときの（００６）の回折ピーク強度Ｉ↑（００６）を分極が下向きのときの（００６）の回折ピーク強度Ｉ↓（００６）で割った回折ピーク強度比Ｉ↑（００６）／Ｉ↓（００６）を表している。 2 and 3 are diagrams showing the relationship between X-ray energy and diffraction peak intensity. In FIG. 2, the horizontal axis represents X-ray energy (keV), and the vertical axis represents the diffraction peak intensity I (006) of (006). In FIG. 2, the diffraction peak intensity at (006) when the polarization is upward is I ↑ (006), and the diffraction peak intensity at (006) when the polarization is downward is I ↓ (006). In FIG. 3, the horizontal axis represents X-ray energy (keV), and the vertical axis represents the diffraction peak intensity I ↑ (006) of (006) when the polarization shown in FIG. 2 is upward. The diffraction peak intensity ratio I ↑ (006) / I ↓ (006) divided by the diffraction peak intensity I ↓ (006) of (006).

図２および図３より、Ｘ線のエネルギーがＺｒのＫ吸収端（Ｚｒ−Ｋ吸収端）より低い場合には、分極が上向きのときの回折ピーク強度Ｉ↑（００６）と、分極が下向きのときの回折ピーク強度Ｉ↓（００６）との間に差が認められた。一方、Ｘ線のエネルギーがＺｒ−Ｋ吸収端より高い場合には、双方の回折ピーク強度Ｉ↑（００６），Ｉ↓（００６）の間にほとんど差は見られなかった。 2 and 3, when the X-ray energy is lower than the Kr absorption edge (Zr-K absorption edge) of Zr, the diffraction peak intensity I ↑ (006) when the polarization is upward and the polarization is downward A difference was observed with respect to the diffraction peak intensity I ↓ (006). On the other hand, when the X-ray energy was higher than the Zr-K absorption edge, there was almost no difference between the diffraction peak intensities I ↑ (006) and I ↓ (006).

このように、分極が上向きと下向きのＰＺＴ膜１４について、その構成元素であるＺｒのＫ吸収端近傍のエネルギーを有するＸ線を用いて回折測定を行い、各エネルギーについて回折ピーク強度Ｉ（００６）を求めると、回折ピーク強度Ｉ（００６）が分極の極性によって異なるエネルギー範囲が存在する。 As described above, the PZT film 14 whose polarization is upward and downward is subjected to diffraction measurement using X-rays having energy in the vicinity of the K absorption edge of Zr, which is a constituent element, and the diffraction peak intensity I (006) for each energy. , There is an energy range in which the diffraction peak intensity I (006) varies depending on the polarity of polarization.

この第１の実施の形態では、このような性質、すなわち所定方位の回折ピーク強度が分極の極性によって異なるエネルギー範囲のＸ線を用いて、ＰＺＴ膜の分極を評価する。
例えば、まず、分極の極性が既知の強誘電体膜を含む評価試料について、その強誘電体膜の構成元素の吸収端近傍のエネルギーを有するＸ線を用いて回折測定を行い、図２や図３に示したような所定方位（例えば分極方向）の回折ピーク強度や用いたＸ線のエネルギー等をデータベース化しておく。そして、分極方向が同じで分極の極性が未知の強誘電体膜を含む評価試料について、その強誘電体膜の分極の極性によって回折ピーク強度が異なってくるエネルギーのＸ線を用いてその回折測定を行う。得られるその所定方位の回折ピーク強度をデータベースのデータと比較すれば、その評価試料に含まれる強誘電体膜の分極の極性を判別することが可能になる。 In the first embodiment, the polarization of the PZT film is evaluated using X-rays having such properties, that is, the diffraction peak intensity in a predetermined direction and the energy range that differs depending on the polarization polarity.
For example, first, with respect to an evaluation sample including a ferroelectric film whose polarization polarity is known, diffraction measurement is performed using X-rays having energy near the absorption edge of the constituent element of the ferroelectric film. A diffraction peak intensity in a predetermined direction (for example, the polarization direction) as shown in FIG. Then, with respect to an evaluation sample including a ferroelectric film whose polarization direction is the same and whose polarization polarity is unknown, diffraction measurement is performed using X-rays of energy whose diffraction peak intensity varies depending on the polarization polarity of the ferroelectric film. I do. By comparing the obtained diffraction peak intensity in the predetermined direction with the data in the database, it is possible to determine the polarity of polarization of the ferroelectric film included in the evaluation sample.

なお、ここでは、強誘電体膜の分極方向の回折ピークに着目し、それを用いて分極の極性を判別する場合を例示したが、分極方向と直交しない方位の回折ピークについては、図２および図３に示したのと同様の関係が得られ、そのような方位の回折ピークを用いた場合にも、同様に分極の極性を判別することが可能となる。Ｘ線のエネルギーと、分極方向と直交する方位の回折ピーク強度との関係については後述する（図６）。 Here, attention is paid to the diffraction peak in the polarization direction of the ferroelectric film, and the case where the polarity of polarization is discriminated using this is illustrated, but the diffraction peak in the direction not orthogonal to the polarization direction is shown in FIG. The same relationship as shown in FIG. 3 is obtained, and even when a diffraction peak having such an orientation is used, the polarity of polarization can be similarly determined. The relationship between the X-ray energy and the diffraction peak intensity in the direction orthogonal to the polarization direction will be described later (FIG. 6).

上記のような第１の実施の形態の評価方法の流れを図４に示す。
強誘電体の分極を評価するに当たり、まず、分極の極性が未知の強誘電体（極性未知強誘電体）と分極方向が同じで、分極の極性が既知の強誘電体（極性既知強誘電体）の所定のデータを有するデータベースを作成する。 The flow of the evaluation method of the first embodiment as described above is shown in FIG.
In evaluating the polarization of a ferroelectric, first, a ferroelectric whose polarization direction is the same as that of a ferroelectric whose polarity is unknown (polarity unknown ferroelectric) and whose polarization is known (a known polarity ferroelectric). A database having predetermined data is created.

その際は、Ｘ線回折装置を用いて、その強誘電体の構成元素の吸収端近傍のエネルギーＥを有するＸ線で回折測定を行い、その強誘電体の分極方向と直交しない方位（ｈｋｌ）の、分極上向きのときの回折ピーク強度Ｉ↑（ｈｋｌ）を求める（ステップＳ１）。 At that time, using an X-ray diffractometer, diffraction measurement is performed with X-rays having energy E in the vicinity of the absorption edge of the constituent element of the ferroelectric, and the orientation (hkl) not orthogonal to the polarization direction of the ferroelectric The diffraction peak intensity I ↑ (hkl) when the polarization is upward is obtained (step S1).

次いで、Ｘ線回折装置を用いて、エネルギーＥを有するＸ線で回折測定を行い、その強誘電体の分極方向と直交しない方位（ｈｋｌ）の、分極下向きのときの回折ピーク強度Ｉ↓（ｈｋｌ）を求める（ステップＳ２）。 Next, using an X-ray diffractometer, diffraction measurement is performed with X-rays having energy E, and the diffraction peak intensity I ↓ (hkl) in the orientation (hkl) that is not orthogonal to the polarization direction of the ferroelectric material is downward. ) Is obtained (step S2).

ただし、このステップＳ１，Ｓ２において、その回折測定に用いるＸ線には、得られる回折ピーク強度Ｉ↑（ｈｋｌ），Ｉ↓（ｈｋｌ）の値が異なるようなエネルギーＥを有するＸ線を選択する。例えば、強誘電体が図１に示した評価試料のＰＺＴ膜１４のような場合であれば、図２および図３に示したように、Ｚｒ−Ｋ吸収端よりも少し低いエネルギーＥを選択するようにすればよい。 However, in steps S1 and S2, X-rays having energy E such that the obtained diffraction peak intensities I ↑ (hkl) and I ↓ (hkl) are different are selected as X-rays used for the diffraction measurement. . For example, when the ferroelectric is the PZT film 14 of the evaluation sample shown in FIG. 1, as shown in FIGS. 2 and 3, energy E slightly lower than the Zr-K absorption edge is selected. What should I do?

このようにして得られたデータ、すなわちエネルギーＥ、指数（ｈｋｌ）、回折ピーク強度Ｉ↑（ｈｋｌ），Ｉ↓（ｈｋｌ）といったデータを有するデータベースを作成する（ステップＳ３）。 A database having data such as energy E, index (hkl), diffraction peak intensities I ↑ (hkl), I ↓ (hkl) is created (step S3).

分極の極性が未知の強誘電体（極性未知強誘電体）についてその評価を行う際には、まず、Ｘ線回折装置を用いて、エネルギーＥを有するＸ線で回折測定を行い、分極方向と直交しない方位（ｈｋｌ）の回折ピーク強度Ｉ（ｈｋｌ）を求める（ステップＳ４）。 When evaluating ferroelectrics whose polarization polarity is unknown (polarity unknown ferroelectrics), first, using an X-ray diffractometer, diffraction measurement is performed with X-rays having energy E, and the polarization direction is determined. A diffraction peak intensity I (hkl) in a non-orthogonal orientation (hkl) is obtained (step S4).

そして、エネルギーＥおよび指数（ｈｋｌ）にて、ステップＳ４で得られた回折ピーク強度Ｉ（ｈｋｌ）を、ステップＳ１〜Ｓ３で作成されたデータベースの回折ピーク強度Ｉ↑（ｈｋｌ），Ｉ↓（ｈｋｌ）と比較することにより、その強誘電体の分極の上向き、下向きを判別する（ステップＳ５）。なお、このステップＳ５において、分極の極性の判別に加え、上向きと下向きの比率を算出するようにしてもよい。 Then, with the energy E and the index (hkl), the diffraction peak intensity I (hkl) obtained in step S4 is used as the diffraction peak intensity I ↑ (hkl), I ↓ (hkl) in the database created in steps S1 to S3. ) To determine whether the polarization of the ferroelectric is upward or downward (step S5). In step S5, in addition to determining the polarity of polarization, an upward / downward ratio may be calculated.

このように、第１の実施の形態の評価方法では、分極の極性が既知の強誘電体のＸ線回折測定を行い、用いたＸ線のエネルギー、回折ピークの指数、分極の極性、回折ピーク強度を含むデータベースをあらかじめ作成しておき、分極の極性が未知の強誘電体のＸ線回折測定を行って、その測定結果をデータベースのデータと比較することで、その強誘電体の分極の極性を判別する。 As described above, in the evaluation method according to the first embodiment, X-ray diffraction measurement is performed on a ferroelectric material whose polarization polarity is known, and the X-ray energy used, the index of the diffraction peak, the polarity of the polarization, the diffraction peak Create a database including the intensity in advance, perform X-ray diffraction measurement of the ferroelectric whose polarization polarity is unknown, and compare the measurement result with the data in the database. Is determined.

この第１の実施の形態の評価方法の場合、Ｘ線回折測定の際には、強誘電体の分極が上向きであると下向きであるとを問わず、その試料表面に必ずしもその強誘電体が露出していることを要しない。例えば、Ｘ線回折測定の試料は、図１に示したような強誘電体キャパシタを構成しているものであっても構わない。したがって、強誘電体の分極の極性を評価するに当たり、その強誘電体を含む試料の加工は不要である。 In the evaluation method of the first embodiment, in the X-ray diffraction measurement, the ferroelectric material is not necessarily present on the sample surface regardless of whether the polarization of the ferroelectric material is upward or downward. It doesn't need to be exposed. For example, the sample for X-ray diffraction measurement may constitute a ferroelectric capacitor as shown in FIG. Therefore, in evaluating the polarity of the polarization of the ferroelectric material, it is not necessary to process the sample containing the ferroelectric material.

また、例えば、ＦｅＲＡＭの製造においては、強誘電体キャパシタを構成する強誘電体膜の形成後であれば、ＦｅＲＡＭの完成までのいずれの段階においても、このような評価方法を適用して、その強誘電体膜の分極の極性を評価することができる。 Further, for example, in the manufacture of FeRAM, such an evaluation method is applied at any stage up to the completion of FeRAM as long as it is after the formation of the ferroelectric film constituting the ferroelectric capacitor. The polarity of polarization of the ferroelectric film can be evaluated.

以上述べたように、強誘電体の分極の極性の評価に、この第１の実施の形態の評価方法を用いることにより、強誘電体の分極の極性を非破壊・非接触で評価することができると共に、その分極の極性を適正にかつ簡便に評価することができる。 As described above, it is possible to evaluate the polarization polarity of the ferroelectric material in a non-destructive / non-contact manner by using the evaluation method of the first embodiment for evaluating the polarization polarity of the ferroelectric material. In addition, the polarity of the polarization can be evaluated appropriately and simply.

次に、第２の実施の形態について説明する。
強誘電体は、例えば図２に示したように、その構成元素の吸収端近傍のエネルギーを有するＸ線を用いて回折測定を行うと、その吸収端の前後で（吸収端よりエネルギーが低いときと高いときで）回折ピーク強度が大きく変化する。 Next, a second embodiment will be described.
For example, as shown in FIG. 2, when a ferroelectric substance is subjected to diffraction measurement using X-rays having energy near the absorption edge of the constituent element, before and after the absorption edge (when the energy is lower than the absorption edge). The diffraction peak intensity changes greatly.

図２の例の場合、図１に示した評価試料のＰＺＴ膜１４についてＸ線回折測定を行ったときに、分極が上向きのときの回折ピーク強度Ｉ↑（００６）はＺｒ−Ｋ吸収端の前後で減少し、分極が下向きのときの回折ピーク強度Ｉ↓（００６）はＺｒ−Ｋ吸収端の前後で増加している。このことから、例えば、吸収端前後の１７．８ｋｅＶと１８．２ｋｅＶのエネルギーを有するＸ線を用いてそれぞれ回折測定を行い、１７．８ｋｅＶのＸ線を用いて得られる回折ピーク強度Ｉ（００６）よりも、１８．２ｋｅＶのＸ線を用いて得られる回折ピーク強度Ｉ（００６）が増加すれば分極は下向き、減少すれば分極は上向きと判別することができる。 In the case of the example of FIG. 2, when X-ray diffraction measurement is performed on the PZT film 14 of the evaluation sample shown in FIG. 1, the diffraction peak intensity I ↑ (006) when the polarization is upward is the Zr-K absorption edge. The diffraction peak intensity I ↓ (006) decreases before and after the polarization and the polarization is downward, and increases before and after the Zr-K absorption edge. Accordingly, for example, diffraction measurement is performed using X-rays having energy of 17.8 keV and 18.2 keV before and after the absorption edge, and diffraction peak intensity I (006) obtained using X-rays of 17.8 keV. If the diffraction peak intensity I (006) obtained using X-rays of 18.2 keV increases, the polarization can be determined to be downward, and if it decreases, the polarization can be determined to be upward.

第２の実施の形態では、このような性質を利用し、強誘電体の分極の極性を評価する。すなわち、吸収端より低いエネルギーと、吸収端より高いエネルギーの２種類のＸ線を用いて回折測定を行う。そして、吸収端より低いエネルギーのＸ線を用いて得られた所定方位の回折ピーク強度と、吸収端より高いエネルギーのＸ線を用いて得られた所定方位の回折ピーク強度を求め、それらの回折ピーク強度が吸収端を挟んで減少しているかあるいは増加しているかによって、分極の極性を判別する。 In the second embodiment, such a property is utilized to evaluate the polarization polarity of the ferroelectric. That is, diffraction measurement is performed using two types of X-rays, energy lower than the absorption edge and energy higher than the absorption edge. Then, a diffraction peak intensity in a predetermined direction obtained using X-rays having energy lower than that of the absorption edge and a diffraction peak intensity in a predetermined direction obtained using X-rays having energy higher than that of the absorption edge are obtained, and these diffractions are obtained. The polarity of polarization is determined depending on whether the peak intensity decreases or increases across the absorption edge.

図５は第２の実施の形態の評価方法の流れを示す図である。
強誘電体の分極を評価するに当たり、まず、分極の極性が未知の強誘電体（極性未知強誘電体）と分極方向が同じで、分極の極性が既知の強誘電体（極性既知強誘電体）の所定のデータを有するデータベースを作成する。 FIG. 5 is a diagram illustrating the flow of the evaluation method according to the second embodiment.
In evaluating the polarization of a ferroelectric, first, a ferroelectric whose polarization direction is the same as that of a ferroelectric whose polarity is unknown (polarity unknown ferroelectric) and whose polarization is known (a known polarity ferroelectric). A database having predetermined data is created.

その際は、Ｘ線回折装置を用いて、その強誘電体の構成元素の吸収端前後のエネルギーＥ₁，Ｅ₂を有するＸ線でそれぞれ回折測定を行い、エネルギーＥ₁，Ｅ₂それぞれの場合について、その強誘電体の分極方向と直交しない方位（ｈｋｌ）の、分極が上向きのときの回折ピーク強度Ｉ₁↑（ｈｋｌ），Ｉ₂↑（ｈｋｌ）を求める（ステップＳ１０）。 In that case, by using the X-ray diffraction apparatus, it performs diffraction measurement, respectively X-rays having the intensity energy E ₁ of the front and rear absorption edge of the constituent elements of the dielectric, E _2, energy E _1, E ₂ in each case , The diffraction peak intensities I ₁ ↑ (hkl) and I ₂ ↑ (hkl) in the direction (hkl) not orthogonal to the polarization direction of the ferroelectric are obtained (step S10).

次いで、Ｘ線回折装置を用いて、エネルギーＥ₁，Ｅ₂を有するＸ線で回折測定を行い、エネルギーＥ₁，Ｅ₂それぞれの場合について、その強誘電体の分極方向と直交しない方位（ｈｋｌ）の、分極が下向きのときの回折ピーク強度Ｉ₁↓（ｈｋｌ），Ｉ₂↓（ｈｋｌ）を求める（ステップＳ１１）。 Then, using an X-ray diffraction apparatus performs diffraction measured by X-ray with energy E _1, E _2, in each case the energy E _1, E _2, not orthogonal to the polarization direction of the ferroelectric orientation (hkl ), The diffraction peak intensities I ₁ ↓ (hkl) and I ₂ ↓ (hkl) when the polarization is downward are obtained (step S11).

このようにして得られたデータ、すなわちエネルギーＥ₁、指数（ｈｋｌ）、回折ピーク強度Ｉ₁↑（ｈｋｌ），Ｉ₁↓（ｈｋｌ）、およびエネルギーＥ₂、指数（ｈｋｌ）、回折ピーク強度Ｉ₂↑（ｈｋｌ），Ｉ₂↓（ｈｋｌ）といったデータを有するデータベースを作成する（ステップＳ１２）。 The data thus obtained, namely energy E ₁ , index (hkl), diffraction peak intensity I ₁ ↑ (hkl), I ₁ ↓ (hkl), and energy E ₂ , index (hkl), diffraction peak intensity I A database having data such as ₂ ↑ (hkl) and I ₂ ↓ (hkl) is created (step S12).

そして、作成したデータベースのデータを用い、分極が上向きのときの吸収端前後の回折ピーク強度比Ｉ₁↑（ｈｋｌ）／Ｉ₂↑（ｈｋｌ）、および分極が下向きのときの吸収端前後の回折ピーク強度比Ｉ₁↓（ｈｋｌ）／Ｉ₂↓（ｈｋｌ）を算出する（ステップＳ１３）。 Then, using the data of the created database, the diffraction peak intensity ratio before and after the absorption edge when the polarization is upward I ₁ ↑ (hkl) / I ₂ ↑ (hkl), and the diffraction before and after the absorption edge when the polarization is downward The peak intensity ratio I ₁ ↓ (hkl) / I ₂ ↓ (hkl) is calculated (step S13).

分極の極性が未知の強誘電体（極性未知強誘電体）についてその評価を行う際には、まず、Ｘ線回折装置を用いて、エネルギーＥ₁，Ｅ₂を有するＸ線で回折測定を行い、エネルギーＥ₁，Ｅ₂それぞれの場合について、分極方向と直交しない方位（ｈｋｌ）の回折ピーク強度Ｉ₁（ｈｋｌ），Ｉ₂（ｈｋｌ）を求める（ステップＳ１４）。 When evaluating a ferroelectric with unknown polarization polarity (a ferroelectric with unknown polarity), first, using an X-ray diffractometer, diffractometry is performed with X-rays having energies E ₁ and E _2. For each of the energies E ₁ and E ₂ , diffraction peak intensities I ₁ (hkl) and I ₂ (hkl) in an orientation (hkl) not orthogonal to the polarization direction are obtained (step S14).

そして、求めた回折ピーク強度Ｉ₁（ｈｋｌ），Ｉ₂（ｈｋｌ）から、それらの回折ピーク強度比Ｉ₁（ｈｋｌ）／Ｉ₂（ｈｋｌ）を算出する（ステップＳ１５）。
エネルギーＥ₁，Ｅ₂および指数（ｈｋｌ）にて、ステップＳ１５で算出された回折ピーク強度比Ｉ₁（ｈｋｌ）／Ｉ₂（ｈｋｌ）を、ステップＳ１３で算出された回折ピーク強度比Ｉ₁↑（ｈｋｌ）／Ｉ₂↑（ｈｋｌ），Ｉ₁↓（ｈｋｌ）／Ｉ₂↓（ｈｋｌ）と比較することにより、その強誘電体の分極の上向き、下向きを判別する（ステップＳ１６）。なお、このステップＳ１６において、分極の極性の判別に加え、上向きと下向きの比率を算出するようにしてもよい。 Then, the diffraction peak intensity ratio I ₁ (hkl) / I ₂ (hkl) is calculated from the obtained diffraction peak intensities I ₁ (hkl) and I ₂ (hkl) (step S15).
At energy each of E _1, E ₂ and index (hkl), the diffraction peak intensity ratio calculated at Step S15 I ₁ a _{(hkl) / I 2 (hkl} ), the diffraction peak intensity ratio calculated at step S13 I ₁ ↑ By comparing with (hkl) / I ₂ ↑ (hkl), I ₁ ↓ (hkl) / I ₂ ↓ (hkl), the upward and downward polarization of the ferroelectric is discriminated (step S16). In step S16, in addition to the determination of the polarity of polarization, an upward / downward ratio may be calculated.

また、ステップＳ１６の比較の際には、回折ピーク強度比Ｉ₁（ｈｋｌ）／Ｉ₂（ｈｋｌ）とＩ₁↑（ｈｋｌ）／Ｉ₂↑（ｈｋｌ）、あるいは回折ピーク強度比Ｉ₁（ｈｋｌ）／Ｉ₂（ｈｋｌ）とＩ₁↓（ｈｋｌ）／Ｉ₂↓（ｈｋｌ）が、必ずしも同値になることを要しない。吸収端を挟んだ回折ピーク強度の増加あるいは減少の傾向が比較対象間で適合するか否かによって、強誘電体の分極の上向き、下向きの判別を行えばよい。 In the comparison in step S16, the diffraction peak intensity ratios I ₁ (hkl) / I ₂ (hkl) and I ₁ ↑ (hkl) / I ₂ ↑ (hkl), or the diffraction peak intensity ratio I ₁ (hkl) ) / I ₂ (hkl) and I ₁ ↓ (hkl) / I ₂ ↓ (hkl) are not necessarily equal. The upward or downward polarization of the ferroelectric may be discriminated depending on whether or not the tendency of the increase or decrease of the diffraction peak intensity across the absorption edge matches between comparison targets.

このように、第２の実施の形態の評価方法では、強誘電体の構成元素の吸収端前後での回折ピーク強度の変化の仕方（増加するか減少するか）によって、その強誘電体の分極の極性を評価する。これにより、分極の極性を評価すべき強誘電体を含んだ評価試料について、その分極の極性のほかに、強誘電体の膜厚等、回折ピーク強度に影響を及ぼすパラメータが含まれていて、それが変化するような場合であっても、その分極の極性を適正にかつ簡便に評価することができる。 As described above, in the evaluation method according to the second embodiment, the polarization of the ferroelectric material depends on how the diffraction peak intensity changes (increases or decreases) before and after the absorption edge of the constituent element of the ferroelectric material. Assess the polarity. Thereby, for the evaluation sample containing the ferroelectric whose polarization polarity should be evaluated, in addition to the polarity of the polarization, parameters that affect the diffraction peak intensity, such as the thickness of the ferroelectric, are included. Even if it changes, the polarity of the polarization can be evaluated appropriately and simply.

なお、この第２の実施の形態の評価方法の場合、２種類のエネルギーのＸ線は、例えば、強誘電体のＸ線回折測定に用いるＸ線回折装置のＸ線源を交換することによって発生させることができる。また、Ｘ線源の異なる２台のＸ線回折装置を用いて所定のデータを取得するようにしても構わない。 In the evaluation method according to the second embodiment, two types of energy X-rays are generated, for example, by exchanging the X-ray source of the X-ray diffractometer used for ferroelectric X-ray diffraction measurement. Can be made. Also, predetermined data may be acquired using two X-ray diffractometers with different X-ray sources.

次に、第３の実施の形態について説明する。
ここで、まず、図２に示したのと同様に、図１に示したＰＺＴ膜１４を含む評価試料について、Ｚｒ−Ｋ吸収端近傍のエネルギーを有するＸ線を用いて回折測定を行い、分極方向（００１）と直交する方位（６００）の回折ピーク強度を求めた結果について述べる。 Next, a third embodiment will be described.
First, as shown in FIG. 2, the evaluation sample including the PZT film 14 shown in FIG. 1 is subjected to diffraction measurement using X-rays having energy in the vicinity of the Zr-K absorption edge, and polarized. The results of obtaining the diffraction peak intensity in the direction (600) perpendicular to the direction (001) will be described.

図６はＸ線のエネルギーと回折ピーク強度の関係を示す図である。図６において、横軸はＸ線のエネルギー（ｋｅＶ）を表し、縦軸は（６００）の回折ピーク強度Ｉ（６００）を表している。なお、図６中、分極が上向きのときの（６００）の回折ピーク強度はＩ↑（６００）、分極が下向きのときの（６００）の回折ピーク強度はＩ↓（６００）で示している。 FIG. 6 is a graph showing the relationship between X-ray energy and diffraction peak intensity. In FIG. 6, the horizontal axis represents X-ray energy (keV), and the vertical axis represents the diffraction peak intensity I (600) of (600). In FIG. 6, the diffraction peak intensity at (600) when the polarization is upward is indicated by I ↑ (600), and the diffraction peak intensity at (600) when the polarization is downward is indicated by I ↓ (600).

図６より、分極方向と直交する方位（６００）の回折ピーク強度Ｉ↑（６００），Ｉ↓（６００）は、ＰＺＴ膜１４の分極の極性が上向きと下向きで異なる場合にも、差が見られない。 FIG. 6 shows that the diffraction peak intensities I ↑ (600) and I ↓ (600) in the direction (600) orthogonal to the polarization direction are different even when the polarization polarity of the PZT film 14 is different between upward and downward. I can't.

第３の実施の形態では、このような性質を利用し、強誘電体の分極の極性を評価する。例えば、図２および図６の例の場合、分極の極性以外に回折ピーク強度に影響を及ぼすパラメータのひとつであるＰＺＴ膜１４の膜厚が変化したときにも、あるエネルギーにおける回折ピーク強度Ｉ（００６），Ｉ（６００）の回折ピーク強度比Ｉ（００６）／Ｉ（６００）は、ほとんど変化しない。すなわち、ＰＺＴ膜１４の膜厚が変化しても、回折ピーク強度比Ｉ（００６）／Ｉ（６００）を求めれば、回折ピーク強度Ｉ（００６）が回折ピーク強度Ｉ（６００）によって規格化され、膜厚変化による回折ピーク強度変化の要素を取り除き、分極の極性による回折ピーク強度変化の要素のみを取り出すことが可能になる。 In the third embodiment, such a property is utilized to evaluate the polarization polarity of the ferroelectric. For example, in the example of FIGS. 2 and 6, even when the film thickness of the PZT film 14 which is one of the parameters affecting the diffraction peak intensity other than the polarity of polarization changes, the diffraction peak intensity I ( 006), I (600) diffraction peak intensity ratio I (006) / I (600) hardly changes. That is, even if the film thickness of the PZT film 14 changes, if the diffraction peak intensity ratio I (006) / I (600) is obtained, the diffraction peak intensity I (006) is normalized by the diffraction peak intensity I (600). Thus, it is possible to remove the element of the change in the diffraction peak intensity due to the change in the film thickness and to extract only the element of the change in the diffraction peak intensity due to the polarity of the polarization.

図７は第３の実施の形態の評価方法の流れを示す図である。
強誘電体の分極を評価するに当たり、まず、分極の極性が未知の強誘電体（極性未知強誘電体）と分極方向が同じで、分極の極性が既知の強誘電体（極性既知強誘電体）の所定のデータを有するデータベースを作成する。 FIG. 7 is a diagram illustrating the flow of the evaluation method according to the third embodiment.
In evaluating the polarization of a ferroelectric, first, a ferroelectric whose polarization direction is the same as that of a ferroelectric whose polarity is unknown (polarity unknown ferroelectric) and whose polarization is known (a known polarity ferroelectric). A database having predetermined data is created.

その際は、Ｘ線回折装置を用いて、その強誘電体の構成元素の吸収端近傍のエネルギーＥを有するＸ線で回折測定を行い、その強誘電体の分極方向と直交しない方位（ｈ₁ｋ₁ｌ₁）の分極上向きのときの回折ピーク強度Ｉ↑（ｈ₁ｋ₁ｌ₁）と、分極方向と直交する方位（ｈ₂ｋ₂ｌ₂）の分極上向きのときの回折ピーク強度Ｉ↑（ｈ₂ｋ₂ｌ₂）を求める（ステップＳ２０）。 At that time, using an X-ray diffractometer, diffraction measurement is performed with X-rays having energy E in the vicinity of the absorption edge of the constituent element of the ferroelectric, and an orientation (h ₁₎ that is not orthogonal to the polarization direction of the ferroelectric. k ₁ l ₁₎ and the diffraction peak intensity _{_{I ↑ (h 1 k 1 l}} 1) when the polarization upward, the diffraction peak intensity when the polarization upward orientation perpendicular to the polarization direction _{_{_{(h 2 k 2 l 2)}}} I ↑ (h ₂ k ₂ l ₂ ) is obtained (step S20).

次いで、Ｘ線回折装置を用いて、エネルギーＥを有するＸ線で回折測定を行い、その強誘電体の分極方向と直交しない方位（ｈ₁ｋ₁ｌ₁）の分極下向きのときの回折ピーク強度Ｉ↓（ｈ₁ｋ₁ｌ₁）と、分極方向と直交する方位（ｈ₂ｋ₂ｌ₂）の分極下向きのときの回折ピーク強度Ｉ↓（ｈ₂ｋ₂ｌ₂）を求める（ステップＳ２１）。 Next, using an X-ray diffractometer, diffraction measurement is performed with X-rays having energy E, and the diffraction peak intensity when the direction of polarization (h ₁ k ₁ l ₁ ) is not perpendicular to the polarization direction of the ferroelectric material. I ↓ (h ₁ k ₁ l ₁ ) and diffraction peak intensity I ↓ (h ₂ k ₂ l ₂ ) when the polarization is downward in the direction (h ₂ k ₂ l ₂ ) orthogonal to the polarization direction are obtained (step S21). ).

このようにして得られたデータ、すなわちエネルギーＥ、指数（ｈ₁ｋ₁ｌ₁）、回折ピーク強度Ｉ↑（ｈ₁ｋ₁ｌ₁），Ｉ↓（ｈ₁ｋ₁ｌ₁）、およびエネルギーＥ、指数（ｈ₂ｋ₂ｌ₂）、回折ピーク強度Ｉ↑（ｈ₂ｋ₂ｌ₂），Ｉ↓（ｈ₂ｋ₂ｌ₂）といったデータを有するデータベースを作成する（ステップＳ２２）。 Data thus obtained, namely energy E, index (h ₁ k ₁ l ₁ ), diffraction peak intensity I ↑ (h ₁ k ₁ l ₁ ), I ↓ (h ₁ k ₁ l ₁ ), and energy A database having data such as E, index (h ₂ k ₂ l ₂ ), diffraction peak intensity I ↑ (h ₂ k ₂ l ₂ ), I ↓ (h ₂ k ₂ l ₂ ) is created (step S22).

そして、作成したデータベースのデータを用い、分極が上向きのときの回折ピーク強度比Ｉ↑（ｈ₁ｋ₁ｌ₁）／Ｉ↑（ｈ₂ｋ₂ｌ₂）、および分極が下向きのときの回折ピーク強度比Ｉ↓（ｈ₁ｋ₁ｌ₁）／Ｉ↓（ｈ₂ｋ₂ｌ₂）を算出する（ステップＳ２３）。これにより、分極方向と直交しない方位（ｈ₁ｋ₁ｌ₁）の回折ピーク強度Ｉ↑（ｈ₁ｋ₁ｌ₁），Ｉ↓（ｈ₁ｋ₁ｌ₁）がそれぞれ、分極方向と直交する方位（ｈ₂ｋ₂ｌ₂）の回折ピーク強度Ｉ↑（ｈ₂ｋ₂ｌ₂），Ｉ↓（ｈ₂ｋ₂ｌ₂）によって規格化される。 Then, using the data of the created database, the diffraction peak intensity ratio I ↑ (h ₁ k ₁ l ₁ ) / I ↑ (h ₂ k ₂ l ₂ ) when the polarization is upward, and the diffraction when the polarization is downward peak intensity ratio _{_{I ↓ (h 1 k 1 l}} 1) / I ↓ (h 2 k 2 l 2) is calculated (step S23). Thus, the diffraction peak intensity of orientation that is not orthogonal to the polarization direction _{_{_{(h 1 k 1 l 1)}}} I ↑ (h 1 k 1 l 1), I ↓ (h 1 k 1 l 1) , respectively, orthogonal to the polarization direction orientation (h _{_₂} k ₂ l ₂₎ diffraction peak intensity _{_{I ↑ (h 2 k 2 l}} 2), it is standardized by _{_{I ↓ (h 2 k 2 l}} 2).

分極の極性が未知の強誘電体（極性未知強誘電体）についてその評価を行う際には、まず、Ｘ線回折装置を用いて、エネルギーＥを有するＸ線で回折測定を行い、分極方向と直交しない方位（ｈ₁ｋ₁ｌ₁）の回折ピーク強度Ｉ（ｈ₁ｋ₁ｌ₁）と、分極方向と直交する方位（ｈ₂ｋ₂ｌ₂）の回折ピーク強度Ｉ（ｈ₂ｋ₂ｌ₂）を求める（ステップＳ２４）。 When evaluating ferroelectrics whose polarization polarity is unknown (polarity unknown ferroelectrics), first, using an X-ray diffractometer, diffraction measurement is performed with X-rays having energy E, and the polarization direction is determined. orthogonal non azimuth (h ₁ k ₁ l ₁₎ of the diffraction peak intensity I (h ₁ k ₁ l _1), the diffraction peak intensity of orientation perpendicular to the polarization direction _{_{_{(h 2 k 2 l 2)}}} I (h 2 k 2 l ₂ ) is obtained (step S24).

そして、求めた回折ピーク強度Ｉ（ｈ₁ｋ₁ｌ₁），Ｉ（ｈ₂ｋ₂ｌ₂）から、それらの回折ピーク強度比Ｉ（ｈ₁ｋ₁ｌ₁）／Ｉ（ｈ₂ｋ₂ｌ₂）を算出する（ステップＳ２５）。これにより、分極方向と直交しない方位（ｈ₁ｋ₁ｌ₁）の回折ピーク強度Ｉ（ｈ₁ｋ₁ｌ₁）が、分極方向と直交する方位（ｈ₂ｋ₂ｌ₂）の回折ピーク強度Ｉ（ｈ₂ｋ₂ｌ₂）によって規格化される。 Then, from the obtained diffraction peak intensities I (h ₁ k ₁ l ₁ ) and I (h ₂ k ₂ l ₂ ), their diffraction peak intensity ratios I (h ₁ k ₁ l ₁ ) / I (h ₂ k ₂ l ₂ ) is calculated (step S25). Thereby, the diffraction peak intensity I (h ₁ k ₁ l ₁ ) in the direction (h ₁ k ₁ l ₁ ) not orthogonal to the polarization direction is the diffraction peak intensity in the direction (h ₂ k ₂ l ₂ ) orthogonal to the polarization direction. Normalized by I (h ₂ k ₂ l ₂ ).

ステップＳ２５で算出された回折ピーク強度比Ｉ（ｈ₁ｋ₁ｌ₁）／Ｉ（ｈ₂ｋ₂ｌ₂）を、ステップＳ２３で算出された回折ピーク強度比Ｉ↑（ｈ₁ｋ₁ｌ₁）／Ｉ↑（ｈ₂ｋ₂ｌ₂），Ｉ↓（ｈ₁ｋ₁ｌ₁）／Ｉ↓（ｈ₂ｋ₂ｌ₂）と比較することにより、その強誘電体の分極の上向き、下向きを判別する（ステップＳ２６）。なお、このステップＳ２６において、分極の極性の判別に加え、上向きと下向きの比率を算出するようにしてもよい。 The diffraction peak intensity ratio I (h ₁ k ₁ l ₁ ) / I (h ₂ k ₂ l ₂ ) calculated in step S25 is used as the diffraction peak intensity ratio I ↑ (h ₁ k ₁ l ₁ calculated in step S23. ) / I ↑ (h ₂ k ₂ l ₂ ), I ↓ (h ₁ k ₁ l ₁ ) / I ↓ (h ₂ k ₂ l ₂ ) Is determined (step S26). In this step S26, in addition to the determination of the polarity of polarization, an upward / downward ratio may be calculated.

このように、第３の実施の形態の評価方法では、回折ピーク強度を規格化することによって、その強誘電体の分極の極性を評価する。これにより、分極の極性を評価すべき強誘電体を含んだ評価試料について、その分極の極性のほかに回折ピーク強度に影響を及ぼすパラメータが含まれているような場合であっても、その分極の極性を適正にかつ簡便に評価することができる。 Thus, in the evaluation method of the third embodiment, the polarization polarity of the ferroelectric is evaluated by normalizing the diffraction peak intensity. As a result, the evaluation sample including the ferroelectric whose polarization polarity should be evaluated includes the polarization polarity, even if the parameter affecting the diffraction peak intensity is included in addition to the polarization polarity. The polarity can be appropriately and easily evaluated.

また、この第３の実施の形態の評価方法では、評価すべき強誘電体について、その分極の極性のほかに回折ピーク強度に影響を及ぼすパラメータが含まれているような場合で、かつ、上記の第２の実施の形態と異なり強誘電体のＸ線回折測定に単一のエネルギーのＸ線しか使用することができないような場合であっても、強誘電体の分極の極性を適正に評価することができる。 In the evaluation method according to the third embodiment, the ferroelectric material to be evaluated includes a parameter that affects the diffraction peak intensity in addition to the polarity of the polarization. Unlike the second embodiment, even when only a single energy X-ray can be used for the X-ray diffraction measurement of the ferroelectric, the polarity of the polarization of the ferroelectric is properly evaluated. can do.

次に、第４の実施の形態について説明する。
放射光のように任意にＸ線のエネルギーを選択できない、いわゆる実験室系Ｘ線の場合でも、上記のような評価方法を適用して、強誘電体の分極の極性を評価することは可能である。 Next, a fourth embodiment will be described.
Even in the case of so-called laboratory X-rays in which X-ray energy cannot be arbitrarily selected as in the case of synchrotron radiation, it is possible to evaluate the polarity of ferroelectric polarization by applying the above evaluation method. is there.

図８はＸ線のエネルギーと回折ピーク強度の関係を示す図である。図８には、市販のターゲットあるいは管球を用いて、図１に示したのと同様の膜構造で分極が上向きと下向きであることがわかっている評価試料の（１１１）の回折ピーク強度を測定し、分極が上向きのときの回折ピーク強度Ｉ↑（１１１）を、分極が下向きのときの回折ピーク強度Ｉ↓（１１１）で割った回折ピーク強度比Ｉ↑（１１１）／Ｉ↓（１１１）を、Ｘ線のエネルギーに対してプロットしている。 FIG. 8 is a graph showing the relationship between X-ray energy and diffraction peak intensity. FIG. 8 shows the (111) diffraction peak intensity of an evaluation sample that is known to have upward and downward polarization with a film structure similar to that shown in FIG. 1, using a commercially available target or tube. The diffraction peak intensity ratio I ↑ (111) / I ↓ (111) measured by dividing the diffraction peak intensity I ↑ (111) when the polarization is upward by the diffraction peak intensity I ↓ (111) when the polarization is downward ) Is plotted against the energy of the X-rays.

ＰＺＴ膜の構成元素であるＺｒのＫ吸収端より少し低いエネルギーであるＭｏＫα線や、ＴｉのＫ吸収端より少し低いエネルギーであるＴｉＫα線をＸ線源として用い、上記の第１，第３の実施の形態の評価方法を行うことにより、実験室系Ｘ線でもＰＺＴ膜の分極の極性を評価することが可能になる。 Using the MoKα ray, which is a little lower energy than the K absorption edge of Zr, which is a constituent element of the PZT film, and the TiKα ray, which is a little lower energy than the K absorption edge of Ti, as the X-ray source, By performing the evaluation method of the embodiment, it is possible to evaluate the polarity of polarization of the PZT film even by laboratory system X-rays.

また、ＭｏＫα線やＴｉＫα線に加え、ＣｕＫα線やＣｒＫα線のようにＰＺＴ膜の構成元素の吸収端から離れているエネルギーを有するＸ線源を併用することで、上記の第２の実施の形態の評価方法を、実験室系Ｘ線でも行うことが可能になる。 In addition to the MoKα ray and TiKα ray, the X-ray source having energy away from the absorption edge of the constituent elements of the PZT film, such as CuKα ray and CrKα ray, is used in combination, so that the second embodiment described above is used. This evaluation method can be performed even with laboratory X-rays.

なお、上記の第１〜第４の実施の形態で述べた強誘電体の分極の極性の評価は、Ｘ線回折測定に必要なＸ線源その他通常の測定機構を備えたＸ線回折装置と、そのＸ線回折装置によって測定されたデータの処理等を行うコンピュータとを用いて構成される評価装置によって実現することができる。コンピュータは、Ｘ線回折装置と協働する評価プログラムを備え、その評価プログラムが有するアルゴリズムに従って、評価に伴う所定の処理、例えば、Ｘ線回折装置によるＸ線回折測定、回折ピーク強度および回折ピーク強度比の算出、データベースの作成、回折ピーク強度および回折ピーク強度比の所定値との比較、強誘電体の分極の極性の判別、比率の算出等の処理を実行する。 The evaluation of the polarization polarity of the ferroelectric material described in the first to fourth embodiments is performed by using an X-ray diffractometer equipped with an X-ray source necessary for X-ray diffraction measurement and other ordinary measurement mechanisms. Further, it can be realized by an evaluation apparatus configured using a computer that processes data measured by the X-ray diffraction apparatus. The computer includes an evaluation program that cooperates with the X-ray diffractometer, and in accordance with an algorithm included in the evaluation program, predetermined processing associated with the evaluation, for example, X-ray diffraction measurement by the X-ray diffractometer, diffraction peak intensity, and diffraction peak intensity Processing such as calculation of the ratio, creation of a database, comparison of the diffraction peak intensity and the diffraction peak intensity ratio with a predetermined value, determination of the polarity of the polarization of the ferroelectric material, and calculation of the ratio are executed.

また、評価プログラムは、コンピュータで読み取り可能な記録媒体に記録しておくことができる。そのような記録媒体としては、ハードディスク装置（ＨＤＤ）等の磁気記録装置、ＤＶＤ(Digital Versatile Disc)やＣＤ−ＲＯＭ(Compact Disc Read Only Memory)等の光ディスク、ＭＯ(Magneto-Optical disｋ)等の光磁気記録媒体、および半導体メモリ等がある。 The evaluation program can be recorded on a computer-readable recording medium. Such recording media include magnetic recording devices such as hard disk devices (HDD), optical discs such as DVD (Digital Versatile Disc) and CD-ROM (Compact Disc Read Only Memory), and light such as MO (Magneto-Optical disk). There are magnetic recording media, semiconductor memories, and the like.

また、Ｘ線回折装置は、測定する試料を載置するステージを並進できるような構成としてもよい。このような構成のＸ線回折装置の場合、例えばＦｅＲＡＭ製造工程で複数の強誘電体膜（あるいは強誘電体キャパシタ）が形成されているウェハをそのようなステージに載置し、１箇所の強誘電体膜について測定を行った後に、そのステージを並進させ、別の箇所の強誘電体膜について測定が行える。そして、個々の箇所で得られた測定結果を用いて分極の極性を評価すれば、ウェハ上の複数の強誘電体膜に対して分極の極性のマッピングが行えるようになり、ＦｅＲＡＭの品質向上、歩留まり向上等を図ることが可能になる。 Further, the X-ray diffractometer may be configured to translate the stage on which the sample to be measured is placed. In the case of the X-ray diffractometer having such a configuration, for example, a wafer on which a plurality of ferroelectric films (or ferroelectric capacitors) are formed in the FeRAM manufacturing process is placed on such a stage, and one strong point is formed. After measuring the dielectric film, the stage is translated, and the ferroelectric film at another location can be measured. Then, if the polarization polarity is evaluated using the measurement results obtained at the individual locations, the polarization polarity can be mapped to a plurality of ferroelectric films on the wafer, and the quality of FeRAM can be improved. It becomes possible to improve the yield.

（付記１）強誘電体の分極を評価する評価方法において、
前記強誘電体を構成する元素の吸収端近傍のエネルギーを有するＸ線であって、前記強誘電体の分極の極性によって前記強誘電体の分極方向と直交しない方位の回折ピーク強度が異なるエネルギーを有する前記Ｘ線を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定し、
測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別することを特徴とする評価方法。 (Supplementary note 1) In an evaluation method for evaluating the polarization of a ferroelectric,
X-rays having energy in the vicinity of the absorption edge of the element constituting the ferroelectric, and having different diffraction peak intensities in directions not perpendicular to the polarization direction of the ferroelectric depending on the polarization polarity of the ferroelectric Using the X-ray having, measure the diffraction peak intensity of the orientation that is not orthogonal to the polarization direction of the ferroelectric,
An evaluation method comprising: discriminating a polarity of polarization of the ferroelectric using a measured diffraction peak intensity in an orientation not orthogonal to the polarization direction of the ferroelectric.

（付記２）前記強誘電体と同じ分極方向であって、分極が上向きと下向きの極性を有する極性既知強誘電体のそれぞれについて、前記Ｘ線を用いて前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定し、
前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別する際には、
前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度とを比較することによって、前記強誘電体の分極の極性を判別することを特徴とする付記１記載の評価方法。 (Supplementary Note 2) For each of the known polarity ferroelectrics having the same polarization direction as that of the ferroelectric material and having polarizations having upward and downward polarities, the polarization direction of the known polarity ferroelectric material using the X-rays Measure the diffraction peak intensity in a direction that is not orthogonal to
When determining the polarity of polarization of the ferroelectric using the diffraction peak intensity in a direction that is not orthogonal to the polarization direction of the ferroelectric,
By comparing the diffraction peak intensity of an azimuth that is not orthogonal to the polarization direction of the ferroelectric with known polarity and the diffraction peak intensity of an azimuth that is not orthogonal to the polarization direction of the ferroelectric, the polarization of the ferroelectric is The evaluation method according to appendix 1, wherein polarity is discriminated.

（付記３）前記Ｘ線が有するエネルギーとの間に前記吸収端が含まれるようなエネルギーを有する他のＸ線を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定し、
前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別する際には、
前記Ｘ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記他のＸ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度とを用いて、前記強誘電体の分極の極性を判別することを特徴とする付記１記載の評価方法。 (Additional remark 3) The diffraction peak intensity of the direction which is not orthogonal to the said polarization direction of the said ferroelectric is used using the other X-rays which have the energy that the said absorption edge is contained between the energy which the said X-ray has. Measure and
When determining the polarity of polarization of the ferroelectric using the diffraction peak intensity in a direction that is not orthogonal to the polarization direction of the ferroelectric,
Diffraction peak intensity in an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the X-ray and an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the other X-rays The evaluation method according to appendix 1, wherein the polarization polarity of the ferroelectric material is discriminated using the diffraction peak intensity of the ferroelectric material.

（付記４）前記強誘電体と同じ分極方向であって、分極が上向きと下向きの極性を有する極性既知強誘電体のそれぞれについて、前記Ｘ線および前記他のＸ線を用いて前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定し、
前記Ｘ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記他のＸ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度とを用いて、前記強誘電体の分極の極性を判別する際には、
前記Ｘ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記他のＸ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度との回折ピーク強度比と、
前記Ｘ線を用いて測定された前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記他のＸ線を用いて測定された前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度との回折ピーク強度比と、
を比較することによって、前記強誘電体の分極の極性を判別することを特徴とする付記３記載の評価方法。 (Supplementary Note 4) For each of the known polar ferroelectrics having the same polarization direction as that of the ferroelectric substance and having polarities of upward and downward polarization, the known polarities are determined using the X-ray and the other X-rays. Measure the diffraction peak intensity in a direction that is not orthogonal to the polarization direction of the dielectric,
Diffraction peak intensity in an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the X-ray and an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the other X-rays When determining the polarity of the polarization of the ferroelectric using the diffraction peak intensity of
Diffraction peak intensity in an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the X-ray and an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the other X-rays The diffraction peak intensity ratio with the diffraction peak intensity of
Diffraction peak intensity in an orientation not orthogonal to the polarization direction of the known polarity ferroelectric material measured using the X-ray, and the polarization direction of the known polarity ferroelectric material measured using the other X-rays The diffraction peak intensity ratio with the diffraction peak intensity in an orientation not orthogonal to the
The evaluation method according to appendix 3, wherein the polarity of polarization of the ferroelectric is discriminated by comparing.

（付記５）前記Ｘ線を用いて前記強誘電体の分極方向と直交する方位の回折ピーク強度を測定し、
前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別する際には、
前記強誘電体の前記分極方向と直交する方位の回折ピーク強度を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を規格化し、
規格化された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別することを特徴とする付記１記載の評価方法。 (Additional remark 5) The diffraction peak intensity of the direction orthogonal to the polarization direction of the ferroelectric is measured using the X-ray,
When determining the polarity of polarization of the ferroelectric using the diffraction peak intensity in a direction that is not orthogonal to the polarization direction of the ferroelectric,
Using the diffraction peak intensity in the direction orthogonal to the polarization direction of the ferroelectric, normalize the diffraction peak intensity in the direction not orthogonal to the polarization direction of the ferroelectric,
The evaluation method according to appendix 1, wherein the polarization polarity of the ferroelectric is discriminated using a standardized diffraction peak intensity of an orientation not orthogonal to the polarization direction of the ferroelectric.

（付記６）前記強誘電体と同じ分極方向であって、分極が上向きと下向きの極性を有する極性既知強誘電体のそれぞれについて、前記Ｘ線を用いて前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度と前記分極方向と直交する方位の回折ピーク強度とを測定し、
前記極性既知強誘電体の前記分極方向と直交する方位の回折ピーク強度を用いて、前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度を規格化し、
規格化された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別する際には、
規格化された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、規格化された前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度とを比較することによって、前記強誘電体の分極の極性を判別することを特徴とする付記５記載の評価方法。 (Supplementary Note 6) For each of the known polar ferroelectrics having the same polarization direction as that of the ferroelectric material and whose polarization has upward and downward polarities, the polarization direction of the known polarity ferroelectric material using the X-rays Measure the diffraction peak intensity of the azimuth not orthogonal to the direction and the diffraction peak intensity of the azimuth orthogonal to the polarization direction,
Using the diffraction peak intensity in the direction orthogonal to the polarization direction of the ferroelectric substance with known polarity, the diffraction peak intensity in the direction not orthogonal to the polarization direction of the ferroelectric substance with known polarity is normalized,
When discriminating the polarity of the polarization of the ferroelectric using the diffraction peak intensity of the orientation that is not orthogonal to the polarization direction of the normalized ferroelectric,
By comparing the normalized diffraction peak intensity of the azimuth that is not orthogonal to the polarization direction of the ferroelectric and the normalized diffraction peak intensity of the azimuth that is not orthogonal to the polarization direction of the ferroelectric of known polarity The evaluation method according to appendix 5, wherein the polarity of polarization of the ferroelectric is discriminated.

（付記７）強誘電体の分極を評価する処理を行う評価プログラムにおいて、
コンピュータを、
Ｘ線回折装置に、前記強誘電体を構成する元素の吸収端近傍のエネルギーを有するＸ線であって、前記強誘電体の分極の極性によって前記強誘電体の分極方向と直交しない方位の回折ピーク強度が異なるエネルギーを有する前記Ｘ線を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定させる手段、
前記Ｘ線回折装置によって測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別する手段、
として機能させることを特徴とする評価プログラム。 (Additional remark 7) In the evaluation program which performs the process which evaluates the polarization of a ferroelectric substance,
Computer
The X-ray diffractometer has X-rays having energy near the absorption edge of the element constituting the ferroelectric material, and diffracting in a direction not orthogonal to the polarization direction of the ferroelectric material due to the polarization polarity of the ferroelectric material. Means for measuring a diffraction peak intensity in an orientation not orthogonal to the polarization direction of the ferroelectric, using the X-rays having energy different in peak intensity;
Means for discriminating the polarity of polarization of the ferroelectric using a diffraction peak intensity in an orientation not orthogonal to the polarization direction of the ferroelectric measured by the X-ray diffractometer;
An evaluation program characterized by functioning as

（付記８）前記コンピュータを、前記Ｘ線回折装置に、前記強誘電体と同じ分極方向であって、分極が上向きと下向きの極性を有する極性既知強誘電体のそれぞれについて、前記Ｘ線を用いて前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定させる手段として機能させ、
前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別する手段は、
前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度とを比較することによって、前記強誘電体の分極の極性を判別することを特徴とする付記７記載の評価プログラム。 (Supplementary Note 8) The X-ray is used for each of the known ferroelectrics having the same polarization direction as that of the ferroelectric material and the polarization having upward and downward polarities in the X-ray diffractometer. And function as a means for measuring the diffraction peak intensity of the orientation not orthogonal to the polarization direction of the ferroelectric of known polarity,
Means for discriminating the polarity of polarization of the ferroelectric using a diffraction peak intensity in a direction not orthogonal to the polarization direction of the ferroelectric,
By comparing the diffraction peak intensity of an azimuth that is not orthogonal to the polarization direction of the ferroelectric with known polarity and the diffraction peak intensity of an azimuth that is not orthogonal to the polarization direction of the ferroelectric, the polarization of the ferroelectric is The evaluation program according to appendix 7, wherein polarity is discriminated.

（付記９）前記コンピュータを、前記Ｘ線回折装置に、前記Ｘ線が有するエネルギーとの間に前記吸収端が含まれるようなエネルギーを有する他のＸ線を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定させる手段として機能させ、
前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別する手段は、
前記Ｘ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記他のＸ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度とを用いて、前記強誘電体の分極の極性を判別することを特徴とする付記７記載の評価プログラム。 (Supplementary Note 9) The computer uses the X-ray diffractometer with another X-ray having an energy such that the absorption edge is included between the X-ray and the energy of the X-ray. Function as a means to measure the intensity of diffraction peaks in directions that are not orthogonal to the polarization direction,
Means for discriminating the polarity of polarization of the ferroelectric using a diffraction peak intensity in a direction not orthogonal to the polarization direction of the ferroelectric,
Diffraction peak intensity in an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the X-ray and an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the other X-rays The evaluation program according to appendix 7, wherein the polarity of polarization of the ferroelectric is discriminated using the diffraction peak intensity of.

（付記１０）前記コンピュータを、前記Ｘ線回折装置に、前記強誘電体と同じ分極方向であって、分極が上向きと下向きの極性を有する極性既知強誘電体のそれぞれについて、前記Ｘ線および前記他のＸ線を用いて前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定させる手段として機能させ、
前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別する手段は、
前記Ｘ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記他のＸ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度とを用いて、前記強誘電体の分極の極性を判別する際には、
前記Ｘ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記他のＸ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度との回折ピーク強度比と、
前記Ｘ線を用いて測定された前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記他のＸ線を用いて測定された前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度との回折ピーク強度比と、
を比較することによって、前記強誘電体の分極の極性を判別することを特徴とする付記９記載の評価プログラム。 (Supplementary Note 10) The X-ray diffraction apparatus and the X-ray diffractometer have the same polarization direction as that of the ferroelectric material, and each of the known ferroelectric materials having polarizations having upward and downward polarities. Function as a means for measuring the diffraction peak intensity of the orientation not orthogonal to the polarization direction of the ferroelectric substance of known polarity using other X-rays,
Means for discriminating the polarity of polarization of the ferroelectric using a diffraction peak intensity in a direction not orthogonal to the polarization direction of the ferroelectric,
Diffraction peak intensity in an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the X-ray and an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the other X-rays When determining the polarity of the polarization of the ferroelectric using the diffraction peak intensity of
Diffraction peak intensity in an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the X-ray and an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the other X-rays The diffraction peak intensity ratio with the diffraction peak intensity of
Diffraction peak intensity in an orientation not orthogonal to the polarization direction of the known polarity ferroelectric material measured using the X-ray, and the polarization direction of the known polarity ferroelectric material measured using the other X-rays The diffraction peak intensity ratio with the diffraction peak intensity in an orientation not orthogonal to the
The evaluation program according to appendix 9, wherein the polarity of polarization of the ferroelectric is discriminated by comparing the two.

（付記１１）前記コンピュータを、前記Ｘ線回折装置に、前記Ｘ線を用いて前記強誘電体の分極方向と直交する方位の回折ピーク強度を測定させる手段として機能させ、
前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別する手段は、
前記強誘電体の前記分極方向と直交する方位の回折ピーク強度を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を規格化し、
規格化された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別することを特徴とする付記７記載の評価プログラム。 (Supplementary Note 11) The computer is caused to function as a means for causing the X-ray diffractometer to measure a diffraction peak intensity in a direction orthogonal to the polarization direction of the ferroelectric using the X-ray.
Means for discriminating the polarity of polarization of the ferroelectric using a diffraction peak intensity in a direction not orthogonal to the polarization direction of the ferroelectric,
Using the diffraction peak intensity in the direction orthogonal to the polarization direction of the ferroelectric, normalize the diffraction peak intensity in the direction not orthogonal to the polarization direction of the ferroelectric,
8. The evaluation program according to appendix 7, wherein the polarization polarity of the ferroelectric is discriminated using a standardized diffraction peak intensity that is not orthogonal to the polarization direction of the ferroelectric.

（付記１２）前記コンピュータを、
前記Ｘ線回折装置に、前記強誘電体と同じ分極方向であって、分極が上向きと下向きの極性を有する極性既知強誘電体のそれぞれについて、前記Ｘ線を用いて前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度と前記分極方向と直交する方位の回折ピーク強度とを測定させる手段、
前記極性既知強誘電体の前記分極方向と直交する方位の回折ピーク強度を用いて、前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度を規格化する手段、
として機能させ、
規格化された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別する手段は、
規格化された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、規格化された前記極性既知強誘電体の前記分極方向と直交しない方位の回折ピーク強度とを比較することによって、前記強誘電体の分極の極性を判別することを特徴とする付記１１記載の評価プログラム。 (Supplementary note 12)
For each of the known polarity ferroelectrics having the same polarization direction as that of the ferroelectric material and having polarities of upward and downward polarization, the X-ray diffractometer uses the X-rays to determine the polarity of the known ferroelectric material. Means for measuring a diffraction peak intensity in an orientation not orthogonal to the polarization direction and a diffraction peak intensity in an orientation orthogonal to the polarization direction;
Means for normalizing the diffraction peak intensity of the orientation not orthogonal to the polarization direction of the ferroelectric of known polarity, using the diffraction peak intensity of the orientation orthogonal to the polarization direction of the ferroelectric of known polarity;
Function as
Means for discriminating the polarity of polarization of the ferroelectric using a standardized diffraction peak intensity that is not orthogonal to the polarization direction of the ferroelectric,
By comparing the normalized diffraction peak intensity of the azimuth that is not orthogonal to the polarization direction of the ferroelectric and the normalized diffraction peak intensity of the azimuth that is not orthogonal to the polarization direction of the ferroelectric of known polarity The evaluation program according to appendix 11, wherein the polarity of polarization of the ferroelectric is discriminated.

（付記１３）強誘電体の分極を評価する評価装置において、
前記強誘電体を構成する元素の吸収端近傍のエネルギーを有するＸ線であって、前記強誘電体の分極の極性によって前記強誘電体の分極方向と直交しない方位の回折ピーク強度が異なるエネルギーを有する前記Ｘ線を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定する手段と、
測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別する手段と、
を有することを特徴とする評価装置。 (Additional remark 13) In the evaluation apparatus which evaluates the polarization of a ferroelectric substance,
X-rays having energy in the vicinity of the absorption edge of the element constituting the ferroelectric, and having different diffraction peak intensities in directions not perpendicular to the polarization direction of the ferroelectric depending on the polarization polarity of the ferroelectric Means for measuring a diffraction peak intensity of an orientation not orthogonal to the polarization direction of the ferroelectric using the X-ray having;
Means for discriminating the polarity of polarization of the ferroelectric material using a diffraction peak intensity in a direction not orthogonal to the measured polarization direction of the ferroelectric material;
The evaluation apparatus characterized by having.

（付記１４）前記Ｘ線が有するエネルギーとの間に前記吸収端が含まれるようなエネルギーを有する他のＸ線を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を測定する手段を有し、
前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別する手段は、
前記Ｘ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度と、前記他のＸ線を用いて測定された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度とを用いて、前記強誘電体の分極の極性を判別することを特徴とする付記１３記載の評価装置。 (Additional remark 14) The diffraction peak intensity of the direction which is not orthogonal to the said polarization direction of the said ferroelectric is used using the other X-ray which has the energy which the said absorption edge is contained between the energy which the said X-ray has. Having means for measuring,
Means for discriminating the polarity of polarization of the ferroelectric using a diffraction peak intensity in a direction not orthogonal to the polarization direction of the ferroelectric,
Diffraction peak intensity in an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the X-ray and an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the other X-rays 14. The evaluation apparatus according to appendix 13, wherein the polarization polarity of the ferroelectric material is discriminated using the diffraction peak intensity of the ferroelectric material.

（付記１５）前記Ｘ線を用いて前記強誘電体の分極方向と直交する方位の回折ピーク強度を測定する手段を有し、
前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別する手段は、
前記強誘電体の前記分極方向と直交する方位の回折ピーク強度を用いて、前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を規格化し、
規格化された前記強誘電体の前記分極方向と直交しない方位の回折ピーク強度を用いて前記強誘電体の分極の極性を判別することを特徴とする付記１３記載の評価装置。 (Additional remark 15) It has a means to measure the diffraction peak intensity of the direction orthogonal to the polarization direction of the ferroelectric using the X-ray,
Means for discriminating the polarity of polarization of the ferroelectric using a diffraction peak intensity in a direction not orthogonal to the polarization direction of the ferroelectric,
Using the diffraction peak intensity in the direction orthogonal to the polarization direction of the ferroelectric, normalize the diffraction peak intensity in the direction not orthogonal to the polarization direction of the ferroelectric,
14. The evaluation apparatus according to appendix 13, wherein the polarization polarity of the ferroelectric is discriminated using a standardized diffraction peak intensity in a direction not orthogonal to the polarization direction of the ferroelectric.

（付記１６）分極が上向きと下向きの極性を有する極性既知強誘電体のそれぞれの回折ピーク強度を含むデータベースを有していることを特徴とする付記１３記載の評価装置。 (Supplementary note 16) The evaluation apparatus according to supplementary note 13, wherein the evaluation device includes a database including the diffraction peak intensities of the ferroelectrics whose polarizations have an upward polarity and a downward polarity.

評価試料の断面模式図である。It is a cross-sectional schematic diagram of an evaluation sample. Ｘ線のエネルギーと回折ピーク強度の関係を示す図（その１）である。FIG. 2 is a diagram (part 1) showing a relationship between X-ray energy and diffraction peak intensity. Ｘ線のエネルギーと回折ピーク強度の関係を示す図（その２）である。FIG. 2 is a diagram (part 2) illustrating a relationship between X-ray energy and diffraction peak intensity. 第１の実施の形態の評価方法の流れを示す図である。It is a figure which shows the flow of the evaluation method of 1st Embodiment. 第２の実施の形態の評価方法の流れを示す図である。It is a figure which shows the flow of the evaluation method of 2nd Embodiment. Ｘ線のエネルギーと回折ピーク強度の関係を示す図（その３）である。FIG. 3 is a diagram (part 3) illustrating a relationship between X-ray energy and diffraction peak intensity; 第３の実施の形態の評価方法の流れを示す図である。It is a figure which shows the flow of the evaluation method of 3rd Embodiment. Ｘ線のエネルギーと回折ピーク強度の関係を示す図（その４）である。FIG. 4 is a diagram (part 4) illustrating a relationship between X-ray energy and diffraction peak intensity;

Explanation of symbols

１０Ｓｉ基板
１１ＳｉＯ₂膜
１２Ａｌ₂Ｏ₃膜
１３Ｐｔ膜
１４ＰＺＴ膜
１５ＩｒＯ₂膜
10 Si substrate 11 SiO ₂ film 12 Al ₂ O ₃ film 13 Pt film 14 PZT film 15 IrO ₂ film

Claims

An X-ray having an energy of the absorption edge near the elements constituting the ferroelectric, having energy diffraction peak intensity of orientation that is not orthogonal to the polarization direction of the ferroelectric by the polarity of the polarization of the ferroelectric is different Using the X-ray, measure the diffraction peak intensity in an orientation that is not orthogonal to the polarization direction of the ferroelectric,
Using other X-rays having an energy such that the absorption edge is included between the X-rays and the energy of the X-rays, the diffraction peak intensity in a direction not orthogonal to the polarization direction of the ferroelectric is measured,
A diffraction peak intensity of orientation that is not orthogonal to the polarization direction of the ferroelectric measured using the X-ray, not orthogonal to the polarization direction of the ferroelectric measured using the other X-ray orientation And determining the polarity of polarization of the ferroelectric material using the diffraction peak intensity of the ferroelectric material.

  Computer
  An X-ray diffractometer is an X-ray having energy in the vicinity of the absorption edge of an element constituting a ferroelectric material, and having a diffraction peak whose orientation is not orthogonal to the polarization direction of the ferroelectric material due to the polarization polarity of the ferroelectric material Means for measuring a diffraction peak intensity of an orientation not orthogonal to the polarization direction of the ferroelectric using the X-rays having energy different in intensity;
  Diffraction in an orientation that is not orthogonal to the polarization direction of the ferroelectric using other X-rays having energy such that the absorption edge is included between the X-ray diffractometer and the energy of the X-rays Means for measuring peak intensity,
  The diffraction peak intensity measured in the X-ray diffractometer using the X-rays and in the direction not orthogonal to the polarization direction of the ferroelectric material, and measured by the X-ray diffractometer using the other X-rays. Means for discriminating the polarity of polarization of the ferroelectric using a diffraction peak intensity in an orientation not orthogonal to the polarization direction of the ferroelectric;
  An evaluation program characterized by functioning as

  X-rays having energy in the vicinity of the absorption edge of the element constituting the ferroelectric material, and having an energy whose diffraction peak intensity differs in a direction not orthogonal to the polarization direction of the ferroelectric material depending on the polarization polarity of the ferroelectric material Means for measuring a diffraction peak intensity of an orientation not orthogonal to the polarization direction of the ferroelectric using the X-ray;
  Means for measuring a diffraction peak intensity of an orientation not orthogonal to the polarization direction of the ferroelectric using another X-ray having an energy such that the absorption edge is included between the energy of the X-ray and the X-ray; ,
  Diffraction peak intensity in an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the X-ray and an orientation that is not orthogonal to the polarization direction of the ferroelectric material measured using the other X-rays Means for determining the polarity of polarization of the ferroelectric using the diffraction peak intensity of
  The evaluation apparatus characterized by having.