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JP3873775B2 - Method for producing langasite single crystal substrate - Google Patents
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JP3873775B2 - Method for producing langasite single crystal substrate - Google Patents

Method for producing langasite single crystal substrate Download PDF

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Publication number
JP3873775B2
JP3873775B2 JP2002047035A JP2002047035A JP3873775B2 JP 3873775 B2 JP3873775 B2 JP 3873775B2 JP 2002047035 A JP2002047035 A JP 2002047035A JP 2002047035 A JP2002047035 A JP 2002047035A JP 3873775 B2 JP3873775 B2 JP 3873775B2
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Japan
Prior art keywords
substrate
single crystal
etching
acid
crystal substrate
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JP2002047035A
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JP2003249697A (en
Inventor
敬二 豊永
敦 坪井
聡 宇田
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Mitsubishi Materials Corp
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Mitsubishi Materials Corp
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  • Surface Acoustic Wave Elements And Circuit Networks Thereof (AREA)
  • Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)

Description

【0001】
【発明の属する技術分野】
本発明は、弾性表面波デバイスなどの圧電デバイスに好適に用いられるランガサイト系単結晶基板の製造方法に関する。
【0002】
【従来の技術】
従来、圧電体基板をはじめとする単結晶基板では、一方の主面がポリッシング加工により鏡面にされた後、表面状態のクリーニングを目的として、主に湿式エッチングがなされている。ところで、弾性表面波デバイス用の単結晶基板材料では、基板内に伝播するバルク波の裏面反射による影響をなくすため、前記の鏡面とした主面の裏面側を粗面化する対策がとられるが、このような対策により、表裏面の表面状態の違いに起因していわゆるトワイマン効果による反りが生じる。
【0003】
この反りは、基板の割れ性や電極形成におけるフォトリソグラフィー(露光)の精度に悪影響を与え、さらには基板の搬送にも悪影響を与える。したがって、このような悪影響を回避するため、一般に湿式エッチング処理によって基板の反りを修正する処理がなされている。
この基板の反りを修正するために用いられるエッチング液としては、例えば特開昭56−56020号公報に開示されているように、フッ酸(HF)と硝酸(HNO3 )との混合液がある。
【0004】
【発明が解決しようとする課題】
しかしながら、弾性表面波デバイス用の単結晶基板材料として、Ca3 Ga2 Ge414型結晶構造を有するランガサイト系単結晶である、La3 Ga5 SiO14からなる酸化物結晶基板(ウエハ)を用いた場合に、これに対して前記のフッ酸を含むエッチング液(HF+HNO3 )を用いたところ、エッチング前後での反り量の修正が十分になされなかった。
また、このようなエッチング液によって処理すると、基板表面にフッ化ランタン(LaF3 )と考えられる被膜が形成されてしまう。すると、このような被膜が特にポリッシング加工による鏡面に形成された場合に、この鏡面上へのパターン形成や得られるパターンの特性に悪影響が与えられてしまうといった不都合が生じてしまう。
【0005】
本発明は前記事情に鑑みてなされたもので、その目的とするところは、エッチングにより基板表面に被膜が形成されることなく、反りを良好に修正することのできる、ランガサイト系単結晶基板の製造方法を提供することにある。
【0006】
【課題を解決するための手段】
本発明のランガサイト系単結晶基板の製造方法では、ランガサイト系単結晶基板の一方の主面のみを研磨して鏡面にする工程と、該研磨した基板の前記主面およびその裏面を、リン酸、酢酸、硝酸の少なくとも一種と塩酸とを含む溶液で湿式エッチングする工程と、を備えることを前記課題の解決手段とした。
なお、本発明においてランガサイト系単結晶基板とは、Ca3Ga2Ge414型結晶構造を有する単結晶基板のことをいう。
この場合、前記溶液は、塩酸と他の酸との容積比が1:1〜3:1の範囲であることが好ましい。
【0007】
【発明の実施の形態】
以下、本発明を詳しく説明する。
本発明では、例えば弾性表面波デバイスなどの圧電デバイス用基板(ウエハ)として、Ca3 Ga2 Ge414型結晶構造を有するランガサイト系単結晶基板、例えばLa3 Ga5 SiO14単結晶基板を用意する。この単結晶基板は、単結晶をその育成軸に対し直交するようにして内周刃スライシングマシーン等でスライスし、端面加工によって所定寸法の円形基板とすることにより、作製する。
【0008】
次に、この単結晶基板を、両面ラッピング装置によって両面研磨加工し、表裏両面を所望の面粗さにするとともに、該基板を所望の厚さにする。
次いで、この基板について片面のみポリッシング(研磨)を行い、このポリッシング面を鏡面にする。このように片面のみをポリッシングして鏡面にすると、前述したようにトワイマン効果によって鏡面側が凹、その裏面側が凸となるような反りが生じる。
【0009】
次いで、前記の鏡面側およびその裏面側を共にエッチングするべく、前記基板を予め用意したエッチング液に浸漬し、その全面を湿式エッチング処理する。ここで、用いるエッチング液としては、リン酸、酢酸、硝酸の少なくとも一種と塩酸とを含む溶液、すなわち塩酸とリン酸との混合液、塩酸と酢酸との混合液、塩酸と硝酸との混合液、さらには塩酸と他の酸(リン酸、酢酸、硝酸)のうちの二種以上との混合液が用いられる。これら各酸の混合比については、特に限定されないものの、塩酸と他の酸(リン酸、酢酸、硝酸)との二成分系の場合、塩酸:他の酸(容積比)=1:1〜3:1の範囲とするのが好ましい。ここで、各酸については、いずれも特級試薬を用いるものとする。
【0010】
また、このような酸混合液からなるエッチング液でのエッチング条件としては、エッチング液の温度を20〜90℃程度、好ましくは20〜65℃程度とし、浸漬時間を1〜15分程度とするのが望ましい。エッチング液の温度を20℃以上とすれば、十分な反応速度を確保して処理時間を比較的短時間にできるからであり、また特に65℃以下とすることにより、液の反応性が高くなって反応速度が速くなりすぎてしまうのを抑えることができるからである。また、エッチング液の温度をこのような温度範囲とすることにより、処理時間を比較的短時間である前記範囲にすることができる。
このようにして湿式エッチング処理を行った後、エッチング液から基板を引き上げ、さらにこれを流水で十分洗浄することにより、圧電デバイス用基板(ウエハ)などとなるランガサイト系単結晶基板を得る。
【0011】
このようにして湿式エッチング処理を行うと、基板に生じていたトワイマン効果による反りが実用上ほとんど問題のない程度にまで修正され、また、その鏡面には被膜が形成されることなく、前記のポリッシングによる鏡面加工直後の状態が維持されるようになる。なお、この反りの修正については、エッチングによって主面および裏面の応力が緩和されることによると考えられる。すなわち、エッチングの際に被膜の形成がないことから、基板の表裏面ではその表面状態(鏡面と粗面)の違いによって応力のかかり方が異なり、これによって反りが修正されると考えられる。
【0012】
したがって、このようにしてエッチングした後の基板(ウエハ)に弾性表面波デバイスを作製すれば、反りに起因する露光ムラがなくなってパターニングを良好に行うことができ、また被膜に起因してパターニングや得られるパターンの特性に悪影響が与えられてしまうといった不都合もなくなる。さらに、反りに起因して搬送用の吸着パッドによる吸着不良が起き、これによって搬送時に吸着パッドから基板が落下するといった不都合もなくすことができる。
【0013】
【実施例】
以下、実施例により本発明をさらに具体的に説明する。
まず、Ca3 Ga2 Ge414型結晶構造を有するLa3 Ga5 SiO14単結晶をスライスし、端面加工することによって厚さ0.5mm、直径76.2mmの基板(ウエハ)を多数作製した。
次に、これら基板を、両面ラッピング装置によりGC#800の研磨剤を用いて両面研磨加工を行い、その厚さを0.4mmにした。
【0014】
次いで、これら基板についてそれぞれ片面のみポリッシング(研磨)を行い、このポリッシング面を鏡面にし、またその仕上がり厚さを0.35mmとした。このようにして片面のみポリッシングして鏡面にしたところ、これら基板はポリッシングを行った面側が凹形状となり、その反り量は最大で0.2mmとなった。
【0015】
また、これとは別に塩酸、リン酸、酢酸、硝酸をそれぞれ以下に示す容積比率で混合し、エッチング液1〜6を作製した。なお、各酸についてはいずれも特級試薬を用いた。
・エッチング液1;塩酸:リン酸=3:1
・エッチング液2;塩酸:リン酸=1:1
・エッチング液3;塩酸:酢酸=3:1
・エッチング液4;塩酸:酢酸=1:1
・エッチング液5;塩酸:硝酸=3:1
・エッチング液6;塩酸:硝酸=1:1
そして、これら各エッチング液をそれぞれエッチング処理容器に入れ、さらにこれらエッチング処理容器を恒温槽内に入れて30℃に加熱した。
【0016】
次いで、エッチング処理容器内のエッチング液の温度が30℃で均一になったのを確認した後、前記の基板を各エッチング処理容器内に入れ、それぞれのエッチング液に10分間浸漬して湿式エッチングを行った。
このようにして湿式エッチングを行った後、各基板をそれぞれ流水で十分洗浄し、ランガサイト系の単結晶基板を得た。なお、これらの工程についてはそれぞれのエッチング液毎に10回ずつ行い、単結晶基板を10枚ずつ作製した。
【0017】
得られた単結晶基板について、それぞれ反りの状態と鏡面での表面状態とを調べた。得られた結果を以下に示す。なお、反りの状態については、鏡面での凹部と凸部との間の最大距離を測定し、この最大距離についての基板10枚分の平均値によって示す。また、鏡面での表面状態については、被膜の形成および鏡面状態の維持についての観察結果を示す。
【0018】
(エッチング液1)
・反り平均;0.012mm
・表面状態;被膜形成なし。鏡面状態の維持極めて良好。
(エッチング液2)
・反り平均;0.015mm
・表面状態;被膜形成なし。鏡面状態の維持良好。
(エッチング液3)
・反り平均;0.014mm
・表面状態;被膜形成なし。鏡面状態の維持良好。
(エッチング液4)
・反り平均;0.015mm
・表面状態;被膜形成なし。鏡面状態の維持良好。
(エッチング液5)
・反り平均;0.015mm
・表面状態;被膜形成なし。鏡面状態の維持良好。
(エッチング液6)
・反り平均;0.014mm
・表面状態;被膜形成なし。鏡面状態の維持良好。
【0019】
以上の結果より、エッチング液1〜6のいずれを用いた場合にも、反り量が0.02mm以下となり、実用上ほぼ問題のない反り量に改善(修正)されることが確認された。
また、表面状態についても、いずれのエッチング液を用いたものにも鏡面側に被膜の形成が認められなかった。さらに、鏡面状態の維持については、特にエッチング液1では極めて良好に鏡面状態が維持されており、またエッチング液2〜6でも十分良好に鏡面状態が維持されているのが確認された。
【0020】
また、このようにしてエッチング処理を行って形成した基板を用い、これの鏡面側にパターニングして弾性表面波デバイスを作製した。さらに、比較のため、ポリッシングによる鏡面を形成した後、湿式エッチング処理を行わない基板に対しても同様に弾性表面波デバイスを作製した。
このようにして弾性表面波デバイスを作製したところ、湿式エッチングを施した基板については、パターニングの際に露光ムラがないことなどによって歩留まりが90%となり、したがって生産性が極めて良好になることが分かった。また、反りに起因して搬送用の吸着パッドによる吸着不良が起き、これによって搬送時に吸着パッドから基板が落下するといったことも皆無となった。さらに、湿式エッチングによって破砕層が除去されたことにより、得られた弾性表面波デバイスの特性も向上した。
一方、湿式エッチング処理を行わない基板に対して弾性表面波デバイスを作製した場合では、反りに起因する露光ムラのため、歩留まりが50%という低い値になり、また、反りに起因して搬送時に吸着パッドから基板が落下してしまうという問題も生じた。
【0021】
【発明の効果】
以上説明したように本発明のランガサイト系単結晶基板の製造方法は、研磨した基板の主面およびその裏面を、リン酸、酢酸、硝酸の少なくとも一種と塩酸とを含む溶液で湿式エッチングするようにした方法であるから、トワイマン効果によって生じた反りを比較的低温、短時間での湿式エッチングで修正することができ、また、その鏡面に被膜を形成することなく、ポリッシングによる鏡面加工直後の状態を維持することができる。
そして、このように反りのない平坦度の優れた基板を得ることができることから、この基板上に弾性表面波デバイス等の圧電デバイスを作製すれば、反りに起因する露光ムラがなくなることなどによって得られる圧電デバイスの歩留まりを向上することができ、さらに、反りに起因して搬送用の吸着パッドによる吸着不良が起き、これによって搬送時に吸着パッドから基板が落下するといった不都合もなくすことができる。
[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a langasite single crystal substrate that is suitably used for piezoelectric devices such as surface acoustic wave devices.
[0002]
[Prior art]
Conventionally, in a single crystal substrate such as a piezoelectric substrate, wet etching is mainly performed for the purpose of cleaning the surface state after one main surface is made into a mirror surface by polishing. By the way, in the single crystal substrate material for the surface acoustic wave device, in order to eliminate the influence of the back surface reflection of the bulk wave propagating in the substrate, a measure is taken to roughen the back surface side of the main surface as the mirror surface. By such measures, warpage due to the so-called Twiman effect is caused due to the difference in the surface state of the front and back surfaces.
[0003]
This warpage adversely affects the cracking property of the substrate and the accuracy of photolithography (exposure) in electrode formation, and also adversely affects the conveyance of the substrate. Therefore, in order to avoid such adverse effects, a process for correcting the warpage of the substrate is generally performed by a wet etching process.
As an etching solution used for correcting the warpage of the substrate, there is a mixed solution of hydrofluoric acid (HF) and nitric acid (HNO 3 ) as disclosed in, for example, Japanese Patent Laid-Open No. 56-56020. .
[0004]
[Problems to be solved by the invention]
However, as a single crystal substrate material for a surface acoustic wave device, an oxide crystal substrate (wafer) made of La 3 Ga 5 SiO 14 which is a langasite single crystal having a Ca 3 Ga 2 Ge 4 O 14 type crystal structure. In contrast, when the etching solution (HF + HNO 3 ) containing hydrofluoric acid was used, the amount of warpage before and after the etching was not sufficiently corrected.
Further, when processed by such an etching solution, the film that would lanthanum fluoride (LaF 3) on the substrate surface is formed. Then, when such a film is formed on a mirror surface by polishing, inconveniences such as pattern formation on the mirror surface and characteristics of the obtained pattern are adversely affected.
[0005]
The present invention has been made in view of the above circumstances, and the object of the present invention is to provide a langasite-based single crystal substrate capable of satisfactorily correcting warpage without forming a film on the substrate surface by etching. It is to provide a manufacturing method.
[0006]
[Means for Solving the Problems]
In the method for producing a langasite single crystal substrate of the present invention , a step of polishing only one main surface of the langasite single crystal substrate to make a mirror surface, and the main surface and the back surface of the polished substrate are bonded to each other. And a step of performing wet etching with a solution containing at least one of acid, acetic acid, and nitric acid and hydrochloric acid.
In the present invention, the langasite single crystal substrate refers to a single crystal substrate having a Ca 3 Ga 2 Ge 4 O 14 type crystal structure.
In this case, the solution preferably has a volume ratio of hydrochloric acid to other acid in the range of 1: 1 to 3: 1.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
In the present invention, for example, a langasite single crystal substrate having a Ca 3 Ga 2 Ge 4 O 14 type crystal structure, such as a La 3 Ga 5 SiO 14 single crystal substrate, as a substrate (wafer) for a piezoelectric device such as a surface acoustic wave device. Prepare. This single crystal substrate is produced by slicing the single crystal with an inner peripheral slicing machine or the like so as to be orthogonal to the growth axis, and forming a circular substrate of a predetermined size by end face processing.
[0008]
Next, this single crystal substrate is subjected to double-side polishing with a double-side wrapping apparatus to make both the front and back surfaces have a desired surface roughness, and the substrate has a desired thickness.
Next, this substrate is polished (polished) on only one side, and this polished surface is made a mirror surface. When only one surface is polished to make a mirror surface in this way, as described above, a warp occurs such that the mirror surface side is concave and the back surface side is convex due to the Twiman effect.
[0009]
Next, in order to etch both the mirror surface side and the back surface side, the substrate is immersed in an etching solution prepared in advance, and the entire surface is subjected to a wet etching process. The etching solution used here is a solution containing at least one of phosphoric acid, acetic acid, and nitric acid and hydrochloric acid, that is, a mixed solution of hydrochloric acid and phosphoric acid, a mixed solution of hydrochloric acid and acetic acid, and a mixed solution of hydrochloric acid and nitric acid. Furthermore, a mixed solution of hydrochloric acid and two or more kinds of other acids (phosphoric acid, acetic acid, nitric acid) is used. The mixing ratio of these acids is not particularly limited, but in the case of a binary system of hydrochloric acid and other acids (phosphoric acid, acetic acid, nitric acid), hydrochloric acid: other acids (volume ratio) = 1: 1 to 3 : 1 is preferable. Here, a special grade reagent is used for each acid.
[0010]
Moreover, as etching conditions with an etching solution comprising such an acid mixture, the temperature of the etching solution is about 20 to 90 ° C., preferably about 20 to 65 ° C., and the immersion time is about 1 to 15 minutes. Is desirable. This is because if the temperature of the etching solution is set to 20 ° C. or higher, a sufficient reaction rate can be secured and the processing time can be made relatively short. In particular, by setting the temperature to 65 ° C. or lower, the reactivity of the solution is increased. This is because it is possible to prevent the reaction rate from becoming too fast. Further, by setting the temperature of the etching solution in such a temperature range, the processing time can be set to the above range which is a relatively short time.
After performing the wet etching process in this manner, the substrate is pulled up from the etching solution, and further washed with running water to obtain a langasite single crystal substrate to be a piezoelectric device substrate (wafer) or the like.
[0011]
When the wet etching process is performed in this manner, the warping due to the Twiman effect that has occurred on the substrate is corrected to such an extent that there is almost no problem in practice, and the above polishing is performed without forming a film on the mirror surface. The state immediately after the mirror finish by is maintained. The correction of the warpage is considered to be due to the relaxation of the stress on the main surface and the back surface by etching. That is, since no film is formed during etching, the stress is applied differently on the front and back surfaces of the substrate depending on the surface state (mirror surface and rough surface), and it is considered that the warpage is corrected.
[0012]
Therefore, if a surface acoustic wave device is fabricated on the substrate (wafer) after etching in this way, exposure unevenness due to warpage can be eliminated and patterning can be performed satisfactorily. There is no inconvenience that the characteristics of the obtained pattern are adversely affected. Further, the suction failure caused by the suction pad for transport occurs due to the warp, thereby eliminating the inconvenience that the substrate falls from the suction pad during transport.
[0013]
【Example】
Hereinafter, the present invention will be described more specifically with reference to examples.
First, a large number of substrates (wafers) having a thickness of 0.5 mm and a diameter of 76.2 mm are manufactured by slicing a La 3 Ga 5 SiO 14 single crystal having a Ca 3 Ga 2 Ge 4 O 14 type crystal structure and processing the end face. did.
Next, these substrates were subjected to a double-side polishing process using a GC # 800 abrasive by a double-sided lapping apparatus, and the thickness thereof was set to 0.4 mm.
[0014]
Next, each substrate was polished (polished) on only one side, the polishing surface was made a mirror surface, and the finished thickness was 0.35 mm. When only one side was polished to a mirror surface in this way, these substrates had a concave shape on the polished side, and the warpage amount was 0.2 mm at the maximum.
[0015]
Separately, hydrochloric acid, phosphoric acid, acetic acid, and nitric acid were mixed in the following volume ratios to prepare etching solutions 1 to 6, respectively. A special grade reagent was used for each acid.
Etching solution 1; hydrochloric acid: phosphoric acid = 3: 1
Etching solution 2; hydrochloric acid: phosphoric acid = 1: 1
Etching solution 3; hydrochloric acid: acetic acid = 3: 1
Etching solution 4; hydrochloric acid: acetic acid = 1: 1
Etching solution 5; hydrochloric acid: nitric acid = 3: 1
Etching solution 6; hydrochloric acid: nitric acid = 1: 1
Then, each of these etching solutions was put into an etching container, and these etching containers were placed in a thermostatic bath and heated to 30 ° C.
[0016]
Next, after confirming that the temperature of the etching solution in the etching vessel became uniform at 30 ° C., the substrate was placed in each etching vessel and immersed in the respective etching solution for 10 minutes for wet etching. went.
After wet etching was performed in this manner, each substrate was sufficiently washed with running water to obtain a langasite single crystal substrate. These steps were performed 10 times for each etching solution, and 10 single crystal substrates were produced.
[0017]
About the obtained single crystal substrate, the state of curvature and the surface state on the mirror surface were examined. The obtained results are shown below. In addition, about the state of curvature, the maximum distance between the recessed part and convex part in a mirror surface is measured, and it shows by the average value for 10 substrates about this maximum distance. Moreover, about the surface state in a mirror surface, the observation result about formation of a film and maintenance of a mirror surface state is shown.
[0018]
(Etching solution 1)
-Warpage average: 0.012 mm
-Surface condition: No film formation. Very good mirror condition.
(Etching solution 2)
-Warpage average: 0.015 mm
-Surface condition: No film formation. Good mirror surface maintenance.
(Etching solution 3)
-Warpage average: 0.014 mm
-Surface condition: No film formation. Good mirror surface maintenance.
(Etching solution 4)
-Warpage average: 0.015 mm
-Surface condition: No film formation. Good mirror surface maintenance.
(Etching solution 5)
-Warpage average: 0.015 mm
-Surface condition: No film formation. Good mirror surface maintenance.
(Etching solution 6)
-Warpage average: 0.014 mm
-Surface condition: No film formation. Good mirror surface maintenance.
[0019]
From the above results, it was confirmed that, when any of the etching solutions 1 to 6 was used, the warpage amount was 0.02 mm or less, and the warpage amount was improved (corrected) with almost no problem in practical use.
In addition, regarding the surface state, no film was formed on the mirror surface side in any of the etching solutions. Further, regarding the maintenance of the mirror surface state, it was confirmed that the mirror surface state was maintained very well particularly with the etching solution 1, and that the mirror surface state was maintained sufficiently well even with the etching solutions 2 to 6.
[0020]
In addition, a surface acoustic wave device was manufactured by patterning on the mirror surface side of the substrate formed by performing the etching process in this way. Furthermore, for comparison, a surface acoustic wave device was similarly fabricated for a substrate that was not subjected to wet etching after forming a mirror surface by polishing.
When the surface acoustic wave device was produced in this way, it was found that the yield of the substrate subjected to wet etching was 90% due to the fact that there was no exposure unevenness during patterning, and therefore the productivity was extremely good. It was. Further, due to the warp, a suction failure due to the suction pad for transport occurred, and this caused no substrate to fall from the suction pad during transport. Furthermore, the characteristics of the obtained surface acoustic wave device were improved by removing the fractured layer by wet etching.
On the other hand, when a surface acoustic wave device is manufactured for a substrate that is not subjected to wet etching, the yield is a low value of 50% due to exposure unevenness due to warpage, and during transport due to warpage. There also arises a problem that the substrate falls from the suction pad.
[0021]
【The invention's effect】
As described above, in the method for producing a langasite single crystal substrate according to the present invention, the main surface and the back surface of the polished substrate are wet-etched with a solution containing at least one of phosphoric acid, acetic acid, nitric acid and hydrochloric acid. Therefore, the warp caused by the Twiman effect can be corrected by wet etching at a relatively low temperature in a short time, and the state immediately after mirror processing by polishing without forming a film on the mirror surface Can be maintained.
In addition, since a substrate having excellent flatness without warping can be obtained in this way, if a piezoelectric device such as a surface acoustic wave device is produced on this substrate, exposure unevenness due to warping is eliminated. The yield of the piezoelectric device to be produced can be improved, and furthermore, the suction failure caused by the suction pad for transport occurs due to the warp, thereby eliminating the disadvantage that the substrate falls from the suction pad during transport.

Claims (2)

ランガサイト系単結晶基板の一方の主面のみを研磨して鏡面にする工程と、該研磨した基板の前記主面およびその裏面を、リン酸、酢酸、硝酸の少なくとも一種と塩酸とを含む溶液で湿式エッチングする工程と、を備えることを特徴とするランガサイト系単結晶基板の製造方法。A step of polishing only one main surface of the langasite single crystal substrate to make a mirror surface, and a solution containing at least one of phosphoric acid, acetic acid, nitric acid and hydrochloric acid on the main surface and the back surface of the polished substrate And a wet-etching step. A method for producing a langasite single crystal substrate. 前記溶液は、塩酸と他の酸との容積比が1:1〜3:1の範囲であることを特徴とする請求項1記載のランガサイト系単結晶基板の製造方法。2. The method for producing a langasite single crystal substrate according to claim 1, wherein the solution has a volume ratio of hydrochloric acid to another acid in the range of 1: 1 to 3: 1.
JP2002047035A 2002-02-22 2002-02-22 Method for producing langasite single crystal substrate Expired - Fee Related JP3873775B2 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2430824C2 (en) * 2009-07-27 2011-10-10 Федеральное государственное унитарное предприятие Омский научно-исследовательский институт приборостроения Method of producing lanthanum-gallium silicate crystalline elements of y-cut

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008283337A (en) * 2007-05-09 2008-11-20 Epson Toyocom Corp Surface acoustic wave device and method for manufacturing surface acoustic wave device wafer

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2430824C2 (en) * 2009-07-27 2011-10-10 Федеральное государственное унитарное предприятие Омский научно-исследовательский институт приборостроения Method of producing lanthanum-gallium silicate crystalline elements of y-cut

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