JPH07119717B2 - Semiconductor material evaluation equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to a semiconductor material evaluation apparatus for inspecting the presence or absence of foreign matter adhering to the surface of a semiconductor material and automatically analyzing the components thereof.

<Prior Art> Conventionally, the following methods have been proposed as a method for analyzing foreign substances attached to a silicon substrate.

First, the presence or absence of foreign matter on a silicon substrate is inspected over the entire range by using a commercially available wafer foreign matter inspection device for LSI, and an image of the foreign matter is printed out together with the shape figure of the silicon substrate. Then, the silicon substrate is set in an optical microscope, and the foreign matter on the silicon substrate is searched for and observed with reference to the printed out one. Then, the silicon substrate is set in the analyzer. At the present stage, the size of foreign matter, which is a problem in semiconductor manufacturing, is on the order of submicrons. Due to this limitation, an electron beam probe microanalyzer having an electron microscope with a high image resolution as an analyzer or Auger electron spectroscopy analyzers are used.

Then, the foreign matter on the silicon substrate is confirmed using an electron microscope attached to the analyzer, and when this is done, the analyzer is operated to perform the analytical measurement of all the surface deposits adhered on the silicon substrate.

<Problems to be Solved by the Invention> However, the following drawbacks have been pointed out in the case of the above conventional example. That is, although the wafer foreign matter inspection device can determine the location of the foreign matter on the silicon substrate, the operator must then operate the optical microscope or electron microscope to check the foreign matter on the silicon substrate. Considering the fact that the size of is smaller than micron order, the work is troublesome. In particular, it is meaningless to know the tendency of all the components of the foreign matter attached to the silicon substrate, and the troublesomeness of the above work is a great obstacle to the smooth inspection of the silicon substrate.

Further, in the case of an electron probe microanalyzer or an Auger electron spectroscopic analyzer, the composition of the foreign matter attached to the silicon substrate may change due to the irradiation of the electron beam, which may hinder the accurate component analysis.

A more detailed description will be given with reference to FIG. In this figure, the wafer 40 is placed inside the electron probe microanalyzer 50.
The foreign matter 41 attached to the foreign matter 41 is irradiated with the electron beam c, and the electron beam d emitted from the foreign matter 41 at a predetermined angle is detected by the detector 51. That is, when the electron beam probe microanalyzer 50 is used to analyze and measure the foreign matter 41, the irradiation position of the electron beam c, which is a beam, is finely adjusted so that the foreign matter 41 on the wafer 40 is accurately irradiated with the electron beam c. If there are many foreign substances 41 to be analyzed, this adjustment alone is very difficult.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a semiconductor material evaluation apparatus capable of automatically performing accurate analysis of foreign matter adhering to the surface of a semiconductor material. It is in.

<Means for Solving the Problems> The semiconductor material evaluation apparatus according to the present invention inspects the presence or absence of foreign matter attached to the surface of the semiconductor material to be evaluated, and outputs coordinate values giving the attached location of the foreign matter as data. And a total reflection fluorescent X-ray analyzer for measuring the components of the foreign material of the semiconductor material after the movement, and the moving mechanism includes the semiconductor material. A moving stage that is mounted and moves between the foreign matter inspection apparatus and the total reflection X-ray fluorescence analyzer, and when the semiconductor material mounted on the moving stage reaches a measurement position in the foreign matter inspection apparatus and the total reflection X-ray fluorescence analysis apparatus. And a movement stopping means for stopping the movement of the moving stage when the measurement position in the analyzer is reached, and the foreign matter inspection is performed during analysis in the total reflection X-ray fluorescence analyzer. The moving stage is operated based on the coordinate value data output from the device.

<Operation> First, when the foreign matter inspection device is operated, the presence or absence of foreign matter attached to the semiconductor material set therein is inspected. When there is a foreign substance, the data of the coordinate value indicating the location of the foreign substance is further output. When the moving stage operates based on this data, the semiconductor material is carried to the total reflection X-ray fluorescence analyzer, and then foreign matter on the semiconductor material is aligned with the X-ray irradiation position inside the total reflection X-ray fluorescence analyzer. To be done. When the total reflection X-ray fluorescence analyzer is operated, X
The line is irradiated onto the foreign matter, and the component of the foreign matter is measured. Then, when there is a foreign substance whose component measurement has not yet been performed by the total reflection X-ray fluorescence analyzer, X is applied to the foreign substance.
The moving stage is operated to irradiate the line, and the component of the foreign matter is measured through the same process.

<Example> Hereinafter, an example of a semiconductor material evaluation apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a semiconductor material evaluation apparatus, and FIG. 2 is a schematic diagram showing a state in which foreign matter on a wafer is irradiated with X-rays inside a total reflection X-ray fluorescence analysis apparatus.

The semiconductor material evaluation apparatus listed here is an apparatus in which a wafer foreign matter inspection apparatus 10, a total reflection X-ray fluorescence analyzer 20, and a moving mechanism 300 including a moving stage 30 are combined, and a component analysis of a foreign matter 41 attached to a wafer 40 is performed. It has a basic configuration that automatically and accurately. First, the wafer foreign matter inspection device 10 will be described.

Since the wafer foreign matter inspection device 10 is an existing device,
Although not shown in the drawing, the inside of the wafer 40 (corresponding to a semiconductor material) set on the moving stage 30 is scanned and irradiated with a light beam over the entire front surface, and the light beam reflected from this is detected by a detector. The information about the foreign matter 41 attached to the wafer 40 is output as a signal. Wafer particle inspection system 10
In the signal output by, the data indicating the presence or absence of the foreign matter 41 on the wafer 40 and the numerical data of the coordinate values for all of the foreign matter 41 are included. Have been introduced successively.

The main program for controlling the entire device of the present invention is stored in advance in the microcomputer, and the main program is stored in the wafer.
Moving stage based on information about foreign matter 1 adhering to 40
Includes the ability to generate instructions to operate 30.

The moving mechanism 300 has a moving stage 30 and a movement stopping means 310.

The moving stage 30 moves the wafer 40 to the wafer foreign matter inspection apparatus 10
And the measurement position of the total reflection X-ray fluorescence analyzer 20 are alternately moved, and the X-number determined by the wafer foreign matter inspection apparatus 10 and the total reflection X-ray fluorescence analyzer 20 are respectively determined.
The basic configuration is such that the wafer 40 is positioned and controlled with respect to the Y coordinate system and the X'-Y 'coordinate system. Since the wafer foreign matter inspection apparatus 10 and the total reflection X-ray fluorescence analyzer 20 are arranged in parallel, the respective axis directions in the XY coordinate system and the X'-Y 'coordinate system are parallel to each other.

More specifically, reference numeral 31 in the drawing is an XY table, and a wafer 40 can be mounted in the center of the XY table in a positionable manner. The XY table 31 is composed of a moving table 32 connected to a base plate X-axis servo motor 321 and a moving table 33 connected to a Y-axis servo motor 331, and is mounted on a plate-shaped base plate 34. Has been. The base plate 34 is movable in the Y-axis direction by a guide member 35, and a ball screw 36 penetrates through this side surface in the same direction as the guide member 35. Ball screw
A motor (not shown) is connected to one side of the base plate 36. When the motor is operated, the ball screw 36 is rotated, so that the base plate 34 is alternately moved in the Y-axis direction.

In addition, a positioning V-groove 341 that constitutes a movement stopping means 310 is formed in the vertical direction in the center of the front side surface of the base plate 34. The positioning V-groove 341 is parallel to the guide member 35 and is spaced from each other. The notch tips (not shown) of the position detecting contact sensors 37a, 37b constituting the movement stopping means 310 arranged so as to open are inserted. The data of the detection signals of the position detecting contact sensors 37a and 37b are sequentially introduced into the microcomputer and are used to give the timing of stopping the motor.

That is, when the motor is driven, the wafer 40 moves from the total reflection fluorescent X-ray analysis apparatus 20 side to the wafer foreign matter inspection apparatus 10 side, and then the notch tip portion of the position detection contact sensor 37a is the V groove of the base plate 34. When entering 341, the motor stops at this timing. Then, the wafer 40 is positioned at the above-described measurement position of the wafer foreign matter inspection apparatus 10, and the XY table 31 of the wafer 40 is in a state where the positioning control of the XY coordinate system is performed.

On the other hand, when the motor is driven in the opposite direction to the above, the wafer 40 moves from the wafer foreign matter inspection device 10 side to the total reflection X-ray fluorescence analyzer 20 side, and then the position detection contact sensor 37.
When the notch tip of b enters the V groove 341 of the base plate 34,
The motor stops at this timing. Then the wafer
40 is positioned at the above-mentioned measurement position of the total reflection X-ray fluorescence analyzer 20, and thereby the positioning control of the X'-Y 'coordinate system by the XY table 31 of the wafer 40 is performed.

Next, the total reflection X-ray fluorescence analyzer 20 will be described.

The total reflection X-ray fluorescence analyzer 20 is a wafer foreign matter inspection device 10
Similarly to the existing apparatus, as shown in FIG. 2, the surface of the wafer 40 set on the moving stage 30 is irradiated with X-rays a from a side at a predetermined angle, and the characteristic X-rays emitted from this are emitted. b is detected by the scintillator 21, and data relating to the components of the plurality (four in the illustrated example) of the foreign matter 41 attached to the wafer 40 is output as a signal.
This signal is successively introduced into the microcomputer.

The operation of the semiconductor material evaluation apparatus configured as described above will be described.

First, after setting the wafer 40 on the moving stage 30, the moving stage 30 is operated to stop and position the wafer 40 at the measurement position of the wafer foreign matter inspection apparatus 10 by the movement stopping means 310. If necessary, the XY table 31 is operated to control the positioning of the wafer 40 in the XY coordinate system. After that, the wafer foreign matter inspection device 10 is operated, and if there is no foreign matter 41 on the wafer 40, the foreign matter is displayed on the display (not shown) or the like connected to the microcomputer 40.
Although there is a display indicating that there is no 41, if there is a foreign substance 41, the coordinate value data of the XY coordinate system is stored in a predetermined memory of the microcomputer 40 for all of them. Then, the moving stage 30 is operated to position the wafer 40 at the measuring position of the total reflection X-ray fluorescence analyzer 20 by stopping the moving means 310. Before and after this, all the coordinate value data of the foreign matter 41 in the XY coordinate system are Lorentz transformed into the coordinate value data in the X'-Y 'coordinate system and stored in a predetermined memory.

By the way, the total reflection X-ray fluorescence analyzer 20 can measure the area corresponding to the size of the scintillator 21 at a time, as shown in FIG. Therefore, in the proposed device,
The wafer 40 is divided into each measurable region in the X'-Y 'coordinate system of the total reflection X-ray fluorescence analyzer 20, and each region in which the foreign substance 41 exists is irradiated with the X-ray a.

More specifically, X′− of the foreign matter 41 stored in the memory
The coordinate value data based on the Y'coordinate system is searched for each coordinate area corresponding to the measurable area. If the foreign matter 41 is present in the coordinate area, X-Y to irradiate the measurable area with X-ray a. Operate table 31. By repeating this, the component analysis for all the foreign matters 41 attached to the wafer 40 is performed by the total reflection X-ray fluorescence analyzer 20. The data of the measurement and analysis are sequentially guided to the microcomputer, where the analysis result of the foreign matter 41 attached to the wafer 40 is displayed on the display or the like, and the material evaluation of the wafer 40 is also performed. This completes the analytical measurement of the wafer 40.

The semiconductor material evaluation apparatus according to the present invention is not limited to the above-mentioned embodiment, and the moving stage may take a form to which a turntable is applied from the viewpoint of structural simplification.

<Effects of the Invention> As described above, in the case of the semiconductor material evaluation apparatus according to the present invention, it is possible to automatically analyze the foreign matter adhering to the surface of the semiconductor material due to the apparatus configuration, and perform the troublesome work as in the past. There is no need to do it. Further, in analyzing the composition of all the foreign matters on the semiconductor material, since the range that can be measured at one time is large, the semiconductor material side and the total reflection X-ray fluorescence analyzer side are irrespective of the size of the foreign matter. The alignment can be made very easy. Moreover, since the foreign matter is irradiated with X-rays instead of the electron beam, there is a great merit in accurate component analysis of the foreign matter.

In addition, the semiconductor material evaluation apparatus according to the present invention includes a moving stage that is mounted with the semiconductor material and moves between the foreign matter inspection apparatus and the total reflection X-ray fluorescence analyzer, and the semiconductor material mounted on the moving stage. A moving mechanism having a movement stopping means for stopping the movement of the moving stage when reaching the measurement position in the foreign matter inspection device and when reaching the measurement position in the total reflection X-ray fluorescence analysis device is provided. Therefore, the moving mechanism automatically positions the semiconductor material at a predetermined position in both the foreign matter inspection device and the total reflection X-ray fluorescence analysis device, so that it is not necessary to perform the troublesome positioning work as in the conventional case, and the inspection can be performed more speedily. It can be performed.

[Brief description of drawings]

1 and 2 are views for explaining an embodiment of a semiconductor material evaluation apparatus according to the present invention. FIG. 1 is a schematic configuration diagram of the semiconductor material evaluation apparatus, and FIG. 2 is total reflection fluorescence. It is a schematic diagram which shows a foreign material on a wafer being irradiated with X-rays inside an X-ray analyzer. FIG. 3 is a diagram for explaining the drawbacks of the conventional semiconductor material evaluation apparatus, and is a diagram for explaining, in which the foreign matter on the wafer is irradiated with the electron beam inside the electron beam microanalyzer. It is a schematic diagram which shows a mode that it is. 10 …… Wafer foreign matter inspection device 20 …… Total reflection X-ray fluorescence analyzer 30 …… Moving stage 40 …… Wafer 41 …… Foreign matter

Claims (1)

[Claims] 1. A foreign matter inspection device for inspecting the presence or absence of a foreign matter attached to the surface of a semiconductor material to be evaluated and outputting a coordinate value which gives the attachment location of the foreign matter as data, and a moving mechanism for moving the semiconductor material. And a total reflection X-ray fluorescence analyzer for measuring the components of the foreign matter of the semiconductor material after the movement, wherein the moving mechanism mounts the semiconductor material on the foreign matter inspection apparatus and the total reflection X-ray fluorescence analyzer. And a moving stage that moves between the moving stage and the semiconductor material mounted on the moving stage when the semiconductor material reaches a measuring position in the foreign matter inspection device and a measuring position in the total reflection X-ray fluorescence analyzer. A movement stopping means for stopping the movement, and at the time of analysis in the total reflection X-ray fluorescence analyzer, the movement is based on the coordinate value data output from the foreign substance inspection apparatus. A semiconductor material evaluation apparatus characterized by operating a moving stage.