JPH1050783A - Method and apparatus for evaluating oxide film in semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for evaluating an oxide film deposited on a semiconductor substrate easily over a wide area in a short time with high operability. SOLUTION: In a method for evaluating an oxide film 51 deposited on a semiconductor substrate 50 wherein the characteristics of an objective part of the oxide film 51 are evaluated based on an electric signal received from an electrode formed by bringing a mercury 3 into contact with the objective part using a probe 2 for dripping the mercury 3, the probe 2 is moved continuously on the semiconductor substrate 50 while sustaining the state where the mercury 3 of the probe 2 touches the oxide film 51 and the oxide 51 of large area is measured and evaluated continuously.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method and an apparatus for evaluating an oxide film formed on a semiconductor wafer.
In particular, the present invention relates to a method and an apparatus for evaluating a large-area oxide film formed on a semiconductor substrate.

[0002]

2. Description of the Related Art In the process of manufacturing a semiconductor device, an oxide film is often formed on a semiconductor substrate. Particularly important is the formation of an oxide film having uniform characteristics over a large area on the semiconductor substrate. There is something to make. For example, in the manufacturing process of a silicon wafer, a silicon epitaxial layer, which is a thin silicon single crystal layer, is grown and laminated on a substrate. Inspection of the film thickness and film quality characteristics of the silicon epitaxial layer grown in this manner is based on impurity concentration. The measurement of the impurity concentration of the epitaxial layer is performed by forming an oxide film on the surface.

When an oxide film is formed on a semiconductor wafer as described above, it is necessary to evaluate the oxide film itself. In particular, it is necessary to easily and accurately evaluate an oxide film over a large area.

Conventionally, as a method for evaluating a large-area oxide film on a semiconductor wafer, there is a method in which an electrode is further formed on a semiconductor wafer having an oxide film of interest formed on the surface. Since it is necessary to perform new processing on the wafer, there is a drawback that the preparation of the sample is complicated and the preparation takes a long time.

[0005] Recently, as a non-processing and non-destructive evaluation method of an oxide film, a method of measuring using a mercury probe as an electrode has been implemented. The principle of this method is to use a mercury probe with mercury mounted in the form of droplets at the tip, and apply the tip of the mercury probe to the oxide film to be measured and contact the mercury at the tip with the oxide film. Forms a depletion layer to form a Schottky diode. By measuring characteristic values of the Schottky diode, an oxide film to be measured is evaluated.

Here, from the principle of concentration measurement, the thickness of the oxide film is required to be about 15 Å to 25 Å.

[0007]

As described above, the method for evaluating an oxide film using a mercury probe has a feature that it can be measured nondestructively and without processing. Therefore, as a preferable method, a measuring instrument using a mercury probe is preferred. However, such conventional evaluation methods and evaluation apparatuses are basically configured to be suitable for performing point-like (point-like) measurements.

[0008] Therefore, in order to evaluate an oxide film formed over a large area on a semiconductor wafer, it is necessary to apply a mercury probe to each of a plurality of positions on the semiconductor wafer which are considered to be necessary, and to repeat the measurement. become. However, such an operation is not only complicated but also requires a long operation time, so that it has been difficult to improve measurement productivity.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems and disadvantages of the prior art, and has an object of being excellent in operability, capable of short-time measurement, and easy to measure over a wide area. Another object of the present invention is to provide a method and an apparatus for evaluating an oxide film formed on a semiconductor substrate.

[0010]

According to the present invention, there is provided a method for evaluating an oxide film of a semiconductor device according to the present invention, wherein the mercury is formed on a semiconductor substrate using a probe for dropping mercury. Contact with the part to be evaluated
Evaluating the characteristics of the portion to be evaluated based on the electric signal obtained from the electrode, in the method for evaluating an oxide film formed on a semiconductor substrate, while maintaining a state in which the mercury of the probe is in contact with the oxide film. By continuously moving the probe on the semiconductor substrate, a large-area oxide film is continuously measured and evaluated.

According to the above-described evaluation method, the time for preparing a sample is shortened, and the operability is improved, so that measurement and evaluation can be performed in a short time.

An apparatus for evaluating an oxide film of a semiconductor device according to the present invention includes a probe using mercury to be dropped as an electrode, and a measuring unit that repeats measurement at predetermined time intervals based on an electric signal obtained from the electrode. It is characterized by comprising. According to the above configuration, it is possible to measure and evaluate many evaluation portions in a short time.

In the case where the apparatus for evaluating an oxide film of a semiconductor device according to the present invention includes the driving mechanism for the probe and the measuring unit includes means for controlling the movement of the driving mechanism, the measurement is performed. It is automated, shortens measurement time, and improves operation reliability.

Further, according to the method for evaluating an oxide film of a semiconductor device according to the present invention, the mercury is brought into contact with a portion to be evaluated of the oxide film formed on the semiconductor substrate by using a probe for dropping mercury, thereby forming an electrode and an electrode. None, evaluating the characteristics of the portion to be evaluated based on an electric signal obtained from the electrode, in the method for evaluating an oxide film formed on a semiconductor substrate, using a plurality of the probes, the mercury of each probe is the said It is also possible to adopt a configuration in which, in a state of being in contact with each portion to be evaluated of the oxide film, multiple points are simultaneously measured and evaluated based on each electric signal obtained from each electrode of each probe.

According to the above-described method for evaluating the configuration, multipoint measurement of a large-area oxide film is instantaneously performed at once.

Alternatively, the method for evaluating an oxide film of a semiconductor device according to the present invention is characterized in that the probes are synchronized with each other on a semiconductor substrate while maintaining the state in which each mercury of each probe is in contact with the oxide film. When a large area oxide film is continuously measured and evaluated by moving the probe, the plurality of probes each sweep the large area oxide film, so that the portion to be evaluated is further expanded. Becomes
Moreover, a plurality of measurement results can be obtained at once from a plurality of evaluated portions.

Alternatively, when the method of evaluating an oxide film of a semiconductor device according to the present invention has a configuration in which the movement of each probe is performed along a curve, each probe sweeps a wide range of a portion to be evaluated. And evaluation of a large area becomes easy.

Alternatively, when the method for evaluating an oxide film of a semiconductor device according to the present invention has a configuration in which the movement of each probe is performed along a straight line, each probe sweeps a wide range of the portion to be evaluated without fail. And evaluation over a large area becomes easy.

Further, according to the present invention, there is provided an apparatus for evaluating an oxide film of a semiconductor device, comprising: a plurality of probes using mercury to be dropped as electrodes; May be provided. According to the evaluation device having the above-described configuration, it is possible to quickly perform multi-point measurement and evaluation.

Further, the measuring unit of the apparatus for evaluating an oxide film of a semiconductor device according to the present invention comprises a control means for repeating the measurement at predetermined time intervals based on the electric signal obtained from each of the electrodes. In this case, the operation becomes easy, and continuous measurement and evaluation of many evaluated portions can be performed in a short time.

Alternatively, an apparatus for evaluating an oxide film of a semiconductor device according to the present invention includes a driving mechanism to which each of the probes is attached, and the measuring unit includes means for controlling movement of the driving mechanism. In such a case, it is possible to perform multi-point measurement on a large-area oxide film over a wider range.

In a case where the driving mechanism of the apparatus for evaluating an oxide film of a semiconductor device according to the present invention has a structure in which the probes are moved synchronously along a curve, each probe has a wide range of evaluation targets. A portion can be swept, and continuous measurement and evaluation of a large area are facilitated.

Alternatively, in the case where the driving mechanism of the oxide film evaluation apparatus for a semiconductor device according to the present invention has a configuration in which the probes move synchronously along a straight line, each probe has a wide range of evaluation targets. It is possible to sweep all parts, and continuous measurement and evaluation over a large area are facilitated.

[0024]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram of a first embodiment of an evaluation apparatus for an oxide film of a semiconductor device according to the present invention. As shown in FIG. 1, an evaluation apparatus 1 for an oxide film of a semiconductor device according to the present invention includes a probe 2 for dropping mercury 3 on a tip thereof and an electric signal obtained from the probe 2 at predetermined time intervals. And a measurement unit 10 that repeats measurement.

The probe 2 makes the tip of the probe abut the portion of interest, that is, the portion to be evaluated, of the oxide film 51 formed on the surface of the wafer 50 at the time of measurement, so that the mercury 3 to be dropped is ejected from the nozzle. Then, an electrode is brought into contact with the portion to be evaluated of the oxide film 51. An electric signal obtained from the electrode composed of the mercury 3 is processed by a circuit (not shown) in the probe 2 or is directly input to the measuring unit 10 as a probe output 2a.

In the present embodiment, the measuring unit 10 is constituted by a microcomputer, and the inside thereof includes a CPU 11, an AD converter 13, and a ROM connected to a common bus, respectively.
14, an interface 20 is provided. In addition, it may be configured to include a RAM, a non-volatile memory, or the like not shown in the figure.

The ROM 14 stores the probe output signal processing means 15 in a program format executable by the CPU 11. The ROM 14 also stores other means such as a control monitor not shown in the figure.

The measuring section 10 is further provided with a hardware timer 12 which is not connected to the common bus. The hardware timer 12 issues an interrupt signal 12a at a predetermined time interval, and the interrupt signal 12a.
a is input to the interrupt port INT of the CPU 11.

Further, the probe output 2a is input to the AD converter 13 as an analog signal, converted into a digital value, and taken into the system. Further, a pen recorder 21 is connected to the interface 20.

Next, the operation will be described. When the measurement is started, first, the probe 2 is brought into contact with the first portion to be evaluated of the oxide film 51, and a temporary electrode of mercury 3 is formed at this position. The probe output 2a in this state becomes a digital value via the AD converter 13.

Here, when the hardware timer 12 issues an interrupt signal 12a at a predetermined time interval Δt, the interrupt signal 12a is input to the interrupt port INT of the CPU 11, and the CPU 11 executes an interrupt processing routine. I do. If the contents of this interrupt processing routine are set to execute the probe output signal processing means 15, the CPU 11
Execute

The probe output signal processing means 15 performs processing such as normalization on the basis of the probe output 2a which has become a digital value, and causes the pen recorder 21 to record the processing result via the interface 20.

The operator then puts the probe 2 on the oxide film 5 with the mercury 3 adsorbed on the nozzle by surface tension.
Move in contact with 1. The movement of the probe 2 is performed, for example, like a meandering sweep locus 4 to continuously sweep (or continuously scan) the oxide film 51.

In the course of the continuous sweep, when a predetermined time interval Δt elapses, an interrupt signal 12a is generated again, and the probe output signal processing means 15 is executed in the same manner as described above to measure the oxide film 51 at the corresponding position. The signal is sampled and taken in, and the processing result is recorded on the pen recorder 21 via the interface 20.

As described above, when the probe 2 is continuously moved in contact with the oxide film 51, measurement signals sampled at time intervals Δt are successively recorded in the pen recorder 21, and continuous measurement is performed.

As described above, according to the evaluation apparatus of the present embodiment, the measurement result is automatically and continuously recorded at predetermined time intervals only by the operator moving the probe 2 in contact with the oxide film 51. Therefore, the operability is excellent, and a large number of portions to be measured are measured in a short period of time, so that a large area oxide film can be continuously measured and evaluated. As a result, it is possible to easily obtain data that contributes to improving the yield of semiconductor wafers.

In the above-described configuration, the measurement result is recorded on the pen recorder 21. However, the configuration is not limited to this configuration. For example, the measurement result may be displayed on a display.

FIG. 2 is a block diagram showing a second embodiment of the apparatus for evaluating an oxide film of a semiconductor device according to the present invention.
In the figure, the same parts as those in the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The evaluation apparatus 1A for an oxide film of a semiconductor device according to the second embodiment includes a drive mechanism 5 to which the probe 2 is attached and which automatically moves the probe 2, and further includes a ROM 14A of the measuring unit 10A. , A drive mechanism control means 16 for controlling the operation of the drive mechanism 5.
The drive mechanism control means 16 is stored in a program format executable by the CPU 11.

The driving mechanism 5 can be realized by a structure which is movable on rectangular coordinates having the same configuration as that of an XY table, for example. The driving mechanism control means 16 controls the meandering sweep trajectory 4 in FIG.
The program is produced to be.

The operation of the evaluation apparatus 1A will be described. In a state where the probe 2 attached to the driving mechanism 5 is arranged so as to be in contact with the first portion of the oxide film 51 to be evaluated.
Measurement starts. The CPU 11 controls the driving mechanism control unit 1
6 to control the drive of the drive mechanism 5 and execute the probe output signal processing means 15 immediately upon interruption.

As a result, the probe 2 automatically moves along the sweep locus 4, is sampled at predetermined time intervals during this movement, and the measurement results are continuously recorded on the pen recorder 21. .

FIG. 3 shows an example of sampling the output value V. As shown in the figure, in accordance with the automatic movement along the sweep locus 4, the sweep time elapses, and the data at each sampled position on the oxide film 51 is automatically set as the output value V at each time interval Δt. Are plotted in

As described above, according to this embodiment, the measurement can be automated, so that the reliability of the operation is improved and
Measurement time can be shortened, and oxide film evaluation can be realized at low cost. Further, it is possible to easily evaluate a large-area oxide film.

FIG. 4 is a block diagram showing a third embodiment of the evaluation apparatus for an oxide film of a semiconductor device according to the present invention.
In the figure, the same parts as those in the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The evaluation apparatus 1B for an oxide film of a semiconductor device according to the third embodiment comprises a plurality of probes 2A to 2I each of which has mercury 3 dropped at the tip and a plurality of output signals 2a obtained from the probes 2A to 2I. A measuring unit 10B for selecting and processing one of the signals 30 to 2i, processing the measured signals 2a to 2i after digital conversion, and displaying the processed signals.
It comprises a display device 22 for displaying the result.

Each of the plurality of probes 2A to 2I has an end formed with an oxide film 51 formed on the surface of the wafer 50.
By contacting each portion of interest, that is, each portion to be evaluated, the mercury 3 to be dropped is taken out from each nozzle and brought into contact with each portion to be evaluated of the oxide film 51 to form each electrode. The electric signal obtained from the electrode composed of the mercury 3 is processed by a circuit (not shown) in the probes 2A to 2I or directly output from the probe output signals 2a to 2I.
2i is input to the multiplexer 30.

The multiplexer 30 switches these output signals 2a to 2i with a predetermined time difference and sends out the signals one by one in order. The sent signal is converted into a digital value by the AD converter 13 and converted into a digital value, which is sequentially processed. The switching timing of the multiplexer 30 is provided to the multiplexer 30 as a switching signal 20a from the measuring unit 10B as described later.

In the present embodiment, the measuring unit 10B is constituted by a microcomputer, and the inside thereof includes a CPU 11, an AD converter 13, and an RO connected to a common bus, respectively.
M14B, an interface 20 is provided. Further, a display device 22 is connected to the common bus. Further, a configuration including a RAM, a non-volatile memory, and the like, which are not illustrated in the drawing, may be provided.

The ROM 14B stores the probe output signal processing means 15, the pattern organization means 17, and the multiplexer control means 18, all in the form of a program executable by the CPU 11. The ROM 14 also stores other means such as a control monitor not shown in the figure.

The probe output signal processing means 15 is configured to apply, for example, a process such as normalization to the probe output signals 2a to 2i, which have become digital values, to adjust them to numerical values suitable for display.

The pattern organizing means 17 organizes data suitable for display by the display device 22 based on the numerical values processed by the probe output signal processing means 15.

The multiplexer control means 18 has a switching signal 20a for controlling the switching timing of the multiplexer 30.
And the switching signal 20a is transmitted to the interface 20.
To the multiplexer 30. This switching signal 2
The generation timing of 0a is determined in advance in consideration of the required processing time of the AD converter 13.

Next, the operation will be described. At the start of the measurement, first, the probes 2A to 2I are brought into contact with the respective portions to be evaluated of the oxide film 51. The multiplexer 30 first outputs, for example, the probe output 2a from the probe 2A to the AD converter 13, and the probe output 2a becomes a digital value via the AD converter 13.

The CPU 11 executes the probe output signal processing means 15 to process the probe output 2a. Then C
The PU 11 executes the multiplexer control means 18 to generate the switching signal 20a, and switches the multiplexer 30. As a result, the multiplexer 30 outputs the probe output 2b from the probe 2B to the AD converter 13, and the probe output 2b becomes a digital value via the AD converter 13.

The CPU 11 executes the probe output signal processing means 15 to process the probe output 2b. Then C
The PU 11 executes the multiplexer control means 18 to generate the switching signal 20a, and switches the multiplexer 30.

Hereinafter, when the same operation is repeated to process the probe outputs of all the plurality of probes, the CP
U11 executes the pattern knitting means 17. By executing the pattern knitting means 17, the measurement results of the plurality of probes are knitted into data suitable for display by the display device 22.

FIG. 5 shows an example in which the data processed as described above is displayed on the screen by the pattern organizing means 17. As shown in the figure, a semiconductor wafer is displayed in a perspective view on a screen 80, and output values V1 to V1 are provided at positions on the oxide film corresponding to the portions to be evaluated measured by a plurality of probes. V9 is displayed as a bar graph.

In the display of the screen 80, the output values V1 to V
Among 9, the output values V2 and V9 that are out of the specified value are displayed in a different color from the other output values that are within the specified value, for example, V1. With such a screen configuration, the presence / absence of a defective portion and each defective portion are made clear at a glance, and the evaluation becomes extremely easy.

FIG. 6 shows another example of screen display. As shown in the figure, a top view of a semiconductor wafer is displayed on a screen 81, and output values V1 to V9 are displayed on the oxide film at positions corresponding to respective evaluated portions measured by a plurality of probes. Is displayed as a numerical value. As in the case of the above-described screen display, it is also possible to adopt a configuration in which a numerical value outside the specified value is displayed in a special expression.

As described above, according to the present embodiment, since the multipoint measurement is performed at the same time based on each measurement signal obtained from each electrode of each probe and the evaluation is performed, the multipoint measurement of a large-area oxide film is performed. It can be executed instantaneously and at a glance, thereby dramatically improving the productivity of the evaluation work.

FIG. 7 is a block diagram of a fourth embodiment of the apparatus for evaluating an oxide film of a semiconductor device according to the present invention.
In the figure, the same parts as those in the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted. Hereinafter, an evaluation device according to the fourth embodiment will be described with reference to FIG.

The evaluation apparatus 1C for an oxide film of a semiconductor device according to the fourth embodiment comprises a plurality of probes 2A to 2I, a multiplexer 30, and a plurality of probes 2A to 2I. A drive mechanism 31 for automatically moving the probes 2A to 2I in synchronization with each other, a measuring unit 10C for performing processing after digitally converting the measurement signals 2a to 2i of the probes 2A to 2I and displaying the results, and recording the results. A multi-pen recorder 21A for a built-in interface is provided.

The measuring section 10C is constituted by a microcomputer having a ROM 14C. In ROM14C,
Probe output signal processing means 15, pattern knitting means 1
7. In addition to the multiplexer control means 18, the driving mechanism 3
Each of the drive mechanism control means 19 for controlling the operation 1 is stored in a program format executable by the CPU 11.

The drive mechanism control means 19 transmits a control signal 20 b for controlling the operation of the drive mechanism 31 to the interface 20.
To the drive mechanism 31 via the.

An example of the structure of the drive mechanism 31 is shown in the front view of FIG. FIG. 9 shows a top view thereof. In this configuration example,
A plurality of probes 2A to 2I are mounted at fixed positions on the lower end surface of a disc-shaped frame 32, and an eccentric pin 33 is provided on the upper end surface of the frame 32 in an upright manner. The frame 32 is configured to be movable in the X and Y directions by a rail or the like (not shown) equivalent to the base of the existing XY table, and is not rotatable by itself.

A servo motor 35 is provided above the frame 32.
The guide disk 34 is fixed to the axis of the servomotor 35.
Is installed. A guide hole 34a is provided at an eccentric position of the guide disk 34, and an eccentric pin 33 of the frame 32 is slidably fitted in the guide hole 34a.

When the fixed servo motor 35 rotates, the guide disk 34 also rotates, and the guide hole 34a at the eccentric position moves in a circle around the axis. Along with this, the eccentric pin 33 slidably inserted also moves in a circle, so that the frame 32 and the frame 32
Are moved along a circle as a trajectory.

FIG. 11 is a diagram for explaining such a circular movement locus of each probe. With the circular movement of each probe, the mercury 3 on the oxide film moves as shown, and as a result, a ring-shaped region whose width is the diameter of the mercury 3 is measured by sweeping.

The driving mechanism 31 can be configured as an XY table. In this case, as shown in FIG. 12, a meandering sweep trajectory constituted by a straight line can be taken, and sweeping in a filled state with no space can be performed.

Returning to FIG. 7, the operation of the evaluation device 1C will be described. The probe 2A attached to the drive mechanism 31
The measurement is started in a state where .about.2I are arranged so as to be in contact with the first evaluated portion of the oxide film 51.

The CPU 11 executes the driving mechanism control means 19 to control the driving of the driving mechanism 31 and, at the same time, executes the probe output signal processing means 15 at predetermined intervals based on a software timer driven by software. When one probe output signal is processed, the multiplexer control means 18 is executed to switch and control the multiplexer 30.

Thus, the plurality of probes 2A to 2I
Moves automatically, for example, along the above-mentioned circular sweep locus, and sampling of each probe is performed at predetermined time intervals during the movement.

The measurement results obtained in this manner are continuously recorded on the multi-pen recorder 21A. FIG. 10 shows an example of the output value of each probe based on the circular locus. As shown in the figure, a plurality of samplings are performed for each probe while the rotation angle is between 0 and 2π radians, and output data at each position is automatically plotted. In the case shown in the figure, it can be seen that the oxide film of the probe 2B at a position at a rotation angle of about π radians W is out of the specified value.

As described above, according to the present embodiment, it is possible to quickly perform multipoint measurement and evaluation using a plurality of probes, and furthermore, it is possible to automate the measurement, thereby improving the reliability of operation. However, the measurement time can be reduced, and the oxide film evaluation can be realized at low cost. Further, it is possible to sweep the multi-point measurement of the oxide film having a large area over a wider range without fail, thereby dramatically improving the productivity of the evaluation work.

[0076]

As described above, according to the method for evaluating an oxide film of a semiconductor device according to the first aspect of the present invention, the probe is connected to the semiconductor device while maintaining the state in which the mercury dropped by the probe is in contact with the oxide film. By moving continuously on the substrate, a large area oxide film is continuously measured and evaluated, so that the sample preparation time can be shortened, and the operability is excellent, and the measurement and evaluation can be performed in a short time. Therefore, it is possible to contribute to an improvement in the yield of manufacturing a semiconductor device such as an VLSI.

According to a second aspect of the present invention, an apparatus for evaluating an oxide film of a semiconductor device repeats measurement at predetermined time intervals based on a probe using mercury to be dropped as an electrode and an electric signal obtained from the electrode. Since it is configured to include a measurement unit, it is possible to measure and evaluate many evaluated portions in a short time with excellent operability, and thus to contribute to an improvement in the yield in the semiconductor device manufacturing process. is there.

An apparatus for evaluating an oxide film of a semiconductor device according to a third aspect of the present invention includes a drive mechanism for moving the probe, and the measuring unit also has a means for controlling the movement of the drive mechanism. Therefore, there is an effect that the measurement can be automated, the reliability of the operation can be improved, the measurement time can be shortened, and a low-cost evaluation can be realized.

According to a fourth aspect of the present invention, there is provided a method for evaluating an oxide film of a semiconductor device, comprising the steps of: The multi-point measurement of the large-area oxide film can be performed instantaneously at a glance, and the productivity of the evaluation work can be dramatically improved. Can be improved.

According to a fifth aspect of the present invention, there is provided a method for evaluating an oxide film of a semiconductor device, wherein a plurality of probes are used and each probe is placed on a semiconductor substrate while maintaining a state where each mercury of each probe is in contact with the oxide film. In this configuration, large-area oxide films are continuously measured and evaluated by continuously moving them in synchronization with each other. Since the portion can be made wider, and a plurality of measurement results can be obtained at once from a plurality of evaluated portions, there is an effect that an evaluation operation with higher productivity can be realized.

In the method for evaluating an oxide film of a semiconductor device according to claim 6 of the present invention, each probe is moved along a curve, so that each probe covers a wide range of the portion to be evaluated. Sweep can be performed, and there is an effect that evaluation of a large area can be easily performed.

In the method for evaluating an oxide film of a semiconductor device according to claim 7 of the present invention, the movement of each probe is made along a straight line. Sweep can be performed without omission, and there is an effect that evaluation over a large area can be easily performed.

According to an eighth aspect of the present invention, there is provided an apparatus for evaluating an oxide film of a semiconductor device, comprising: a plurality of probes using mercury to be dropped as electrodes; Since it is configured to include a unit, it is possible to quickly execute multi-point measurement and evaluation.

According to a ninth aspect of the present invention, there is provided an oxide film evaluation apparatus for a semiconductor device, comprising a control means for repeating the measurement at predetermined time intervals based on an electric signal obtained from each electrode by the measuring unit. Since it is configured, it is excellent in operability, enables continuous measurement and evaluation of many evaluated parts in a short time, and thus has the effect of contributing to an improvement in the yield in the semiconductor device manufacturing process.

According to a tenth aspect of the present invention, an apparatus for evaluating an oxide film of a semiconductor device includes a driving mechanism having a plurality of probes mounted thereon, and the measuring section includes a means for controlling movement of the driving mechanism. Since it is configured, multi-point measurement of a large-area oxide film can be performed over a wider range,
Therefore, the productivity of the evaluation work can be dramatically improved.

According to the apparatus for evaluating an oxide film of a semiconductor device according to the eleventh aspect of the present invention, since the driving mechanism is configured to move each probe in synchronization with a curve, each probe is wide. The portion to be evaluated in the range can be swept, and there is an effect that continuous measurement and evaluation of a large area can be easily performed.

According to a twelfth aspect of the present invention, in the apparatus for evaluating an oxide film of a semiconductor device, the driving mechanism is configured to move the respective probes synchronously along a straight line. The portion to be evaluated in the range can be completely swept, and there is an effect that continuous measurement and evaluation over a large area can be easily performed.

As described above, the evaluation method and the evaluation apparatus according to the present invention do not require the operation of forming an electrode on a semiconductor wafer having an oxide film formed on the surface thereof as in the conventional evaluation technique. Also, in the measurement using a mercury probe, evaluation is performed at a low cost without requiring time as in the past,
Therefore, the productivity of the evaluation work can be significantly improved.

[Brief description of the drawings]

FIG. 1 is a block diagram of a first embodiment of a device for evaluating an oxide film of a semiconductor device according to the present invention.

FIG. 2 is a block diagram of a second embodiment of an evaluation apparatus for an oxide film of a semiconductor device according to the present invention.

FIG. 3 is an example of output values of an evaluation device for an oxide film of a semiconductor device according to the present invention.

FIG. 4 is a block diagram of a third embodiment of an evaluation apparatus for an oxide film of a semiconductor device according to the present invention.

FIG. 5 is an example of an output screen of the evaluation device according to the third embodiment shown in FIG. 4;

FIG. 6 is an example of another output screen by the evaluation device of the third embodiment shown in FIG. 4;

FIG. 7 is a block diagram of a fourth embodiment of a device for evaluating an oxide film of a semiconductor device according to the present invention.

FIG. 8 is a front view of an example of a driving mechanism applied to the oxide film evaluation device of the semiconductor device according to the present invention.

FIG. 9 is a top view of the drive mechanism shown in FIG.

FIG. 10 is an example of an output result by the evaluation device of the fourth embodiment shown in FIG. 7;

FIG. 11 is an explanatory diagram of an example of a movement locus of a probe by a drive mechanism applied to the oxide film evaluation device of the semiconductor device according to the present invention.

FIG. 12 is an explanatory diagram of another example of the movement locus of the probe by the drive mechanism applied to the oxide film evaluation device of the semiconductor device according to the present invention.

[Explanation of symbols]

1 .... Evaluation device for oxide film of semiconductor device according to the present invention, 2.
…… Probe, 2a… Probe output, 3… Mercury, 4…
... Sweep locus, 10 ... Measurement unit, 11 ... CPU, 12 ...
... hardware timer, 12a ... interrupt signal,
13 AD converter, 14 ROM, 15 probe output signal processing means, 20 interface, 2
1 ... Pen recorder, 50 ... Wafer with oxide film formed on the surface, 51 ... Oxide film.

Claims (12)

[Claims] An electrode is formed by bringing said mercury into contact with a portion to be evaluated of an oxide film formed on a semiconductor substrate using a probe for dropping mercury thereon, and said mercury is evaluated based on an electric signal obtained from said electrode. Evaluating the characteristics of the portion, in the method of evaluating an oxide film formed on a semiconductor substrate, while continuously maintaining the state where the mercury of the probe is in contact with the oxide film, the probe continuously on the semiconductor substrate A method for evaluating an oxide film of a semiconductor device, characterized in that a large-area oxide film is continuously measured and evaluated by being moved. 2. A probe using mercury to be dropped as an electrode,
An evaluation device for evaluating an oxide film of a semiconductor device, comprising: a measurement unit that repeats measurement at predetermined time intervals based on an electric signal obtained from the electrode. 3. The oxide film of a semiconductor device according to claim 2, further comprising a driving mechanism for moving said probe, and wherein said measuring unit includes means for controlling movement of said driving mechanism. Evaluation device. 4. An electrode is formed by bringing said mercury into contact with a portion to be evaluated of an oxide film formed on a semiconductor substrate using a probe for dropping mercury, and said mercury is evaluated based on an electric signal obtained from said electrode. In the method for evaluating an oxide film formed on a semiconductor substrate, evaluating a characteristic of a portion, wherein a plurality of the probes are used, and the mercury of each probe is in contact with each portion to be evaluated of the oxide film, A method for evaluating an oxide film of a semiconductor device, wherein a multi-point measurement is performed at the same time based on each electric signal obtained from each electrode of each probe for evaluation. 5. A large-area oxide film by continuously moving each probe in synchronization with the semiconductor substrate while keeping the mercury of each probe in contact with the oxide film. 5. The method for evaluating an oxide film of a semiconductor device according to claim 4, wherein said method is configured to continuously measure and evaluate. 6. The method for evaluating an oxide film of a semiconductor device according to claim 5, wherein the movement of each probe is performed along a curve. 7. The method for evaluating an oxide film of a semiconductor device according to claim 5, wherein the movement of each probe is performed along a straight line. 8. A semiconductor device comprising: a plurality of probes each having mercury as an electrode to be dropped thereon; and a measuring unit for simultaneously performing multipoint measurement based on electric signals obtained from each of the electrodes. Oxide film evaluation device. 9. The semiconductor device according to claim 8, wherein said measurement unit includes a control unit that repeats measurement at predetermined time intervals based on an electric signal obtained from each of said electrodes. Oxide film evaluation device. 10. The semiconductor device according to claim 8, further comprising a driving mechanism to which each of said probes is attached, and wherein said measuring unit includes means for controlling movement of said driving mechanism. Oxide film evaluation device. 11. The apparatus for evaluating an oxide film of a semiconductor device according to claim 10, wherein said drive mechanism is configured to move each of said probes synchronously along a curve. 12. The apparatus according to claim 10, wherein the driving mechanism is configured to move the probes synchronously along a straight line.