KR20040048545A - method of manufacturing monitoring wafer of inspection equipment - Google Patents

Abstract

PURPOSE: A method for manufacturing a monitoring substrate of measurement equipment is provided to be capable of forming a reference sample corresponding to a variety of thin films on one semiconductor substrate for reducing the cost of the reference sample. CONSTITUTION: The first and second region are defined on a substrate(100). The second region is larger than the first region. The second and first thin film are sequentially deposited on the substrate. The first thin film pattern(140a) is formed at the first region by carrying out an etching process on the first thin film using the first etching mask pattern having the same size as the first region. The second thin film pattern(120a) is formed at the second region by carrying out an etching process on the second thin film using the second etching mask pattern having the same size as the second region.

Description

Method of manufacturing monitoring wafer of inspection equipment

The present invention relates to a method for manufacturing a monitoring substrate of a semiconductor device, and more particularly, to a method for manufacturing a monitoring substrate of a semiconductor measuring device for measuring thickness of a monitoring system in a semiconductor manufacturing process.

Recently, semiconductor devices that have been applied to products to process high-capacity data in a short time, and implement high-speed response speeds have been increasingly integrated and miniaturized. Therefore, as the thickness of many thin films formed in the semiconductor device is getting thinner and thinner, the importance of an analytical device or analytical technology necessary for structural and chemical analysis of finer regions is highlighted.

In general, a semiconductor device is manufactured by repeatedly performing a unit process such as film formation, etching, diffusion, metal wiring, etc. for forming a pattern having electrical characteristics on a semiconductor substrate. In order to determine the failure of the device, the thickness of the thin film formed for each process is measured.

However, even if the thickness of the thin film of the semiconductor device is measured using the same equipment, due to an error in the process data between the thickness measuring equipment installed for each process, the measured values for the thin film having the same thickness may be different from each other, resulting in confusion of the process. Therefore, in order to measure the thickness of the thin film formed during the manufacturing process of the semiconductor device and to confirm the reliability of the thin film thickness, the measured value of the reference sample which can be compared with the measured value measured during the process is important.

The monitoring substrate including the reference sample is formed to have the same thickness as the thin film having the same properties to be formed during the actual process and serves as an absolute value for the thin film formed during the process. That is, after measuring the thickness of the same reference sample with the thickness measuring equipment installed in each step, and compares the actual thickness of the reference sample and the measured value of the thickness measuring equipment installed in each step the process according to the error of the measured value The program of the measuring equipment installed in the step is modified to obtain an accurate measurement of the film thickness of the semiconductor device formed during the process.

However, in the process for manufacturing a semiconductor device, since a thin film formed of different materials and thin films having different thicknesses are applied in various ways, each reference sample must be manufactured for each type of thin film and the thickness of the thin film. It should be manufactured as. In addition, as the thickness of the thin film and the material applied to form the thin film are rapidly changed in order to improve the design rule or performance of the semiconductor device, the number of times of manufacturing the reference sample is also increased to further perform additional work. in need. In particular, when the thickness of a multilayer thin film made of different materials is measured, a thin film is formed on the upper part even if the lower layer matches the actual thickness of the reference sample due to many variables included in the actual semiconductor manufacturing process. The original thickness of the thin film formed on the lower part may shrink. Therefore, when considering the case of the multilayer thin film, the number of reference samples increases rapidly.

In addition, due to the increase in the number of reference samples having various kinds of thin film characteristics and thicknesses, contamination and management of the reference samples are not easy, and the order of the reference samples introduced into the measurement equipment is reversed. An error in the thickness measurement occurs.

This leads to an increase in costs for the semiconductor manufacturing process and a problem of reducing the throughput of the process.

Accordingly, it is an object of the present invention to provide a method for manufacturing a monitoring substrate for a semiconductor inspection facility comprising a plurality of multilayer thin films on a semiconductor substrate.

1A to 1G are cross-sectional views illustrating a method of manufacturing a monitoring substrate applied to a semiconductor measuring apparatus as a first embodiment of the present invention.

2A to 2I are cross-sectional views illustrating a method of manufacturing a monitoring substrate applied to a semiconductor measuring device as a second embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

100: substrate 120: third thin film

140: second thin film 150: first photoresist pattern

160: second photoresist pattern

Monitoring substrate manufacturing method of a semiconductor device for achieving the above object,

(a) providing a substrate divided into n areas (n is a natural number of two or more) including a first area and a second area wider than the first area;

(b) sequentially stacking n thin films including a first thin film and a second thin film on the substrate;

(c) forming a first thin film pattern present in the first region by etching a first thin film disposed on the second thin film by applying a first etching mask pattern having the same size as the first region; And

(d) etching the second thin film on the n thin film by applying a second etching mask pattern covering the first thin film pattern and having the same size as the second region including the first region. And forming a second thin film pattern present in the second region.

As such, by manufacturing a monitoring substrate including a plurality of reference samples including patterns having different thicknesses and stacked film types on one semiconductor substrate, the semiconductor substrate is formed on one semiconductor substrate and includes different multilayer thin film patterns. A plurality of semiconductor processes can be supported by using a reference sample.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

In the method of manufacturing a monitoring substrate including the multi-referenced sample of the present invention, first, a first area, n (n is a natural number of two or more) including the first area and a second area wider than the first area are included. A substrate divided into regions is prepared. Here, the first area has a first area including a center point of the substrate, and the second area includes a center point of the substrate and has a second area wider than the first area.

Subsequently, n thin films including the second thin film and the first thin film are sequentially stacked on the substrate divided into n areas, and then the second etching mask pattern having the same size as the first area is applied to the second thin film. The first thin film pattern on the thin film is etched to form a first thin film pattern present in the first region.

Herein, the n thin films may use any one selected from the group consisting of an oxide film, a nitride film, a conductive film, and the like, and these may be mixed and used. When the films are stacked on the substrate, an etch stop layer is further formed between the respective thin films.

Specifically, the step of forming the first thin film pattern, a) applying a photoresist film on a substrate on which the second thin film and the first thin film is sequentially laminated, b) corresponding to a region other than the first region Forming a first photoresist pattern exposing the first thin film, c) etching the first thin film exposed by the first photoresist pattern; And d) removing the first photoresist pattern.

Subsequently, the second thin film positioned on the n thin film is etched by applying a second etching mask pattern covering the first thin film pattern and having the same size as the second area including the first area. The second thin film pattern existing on the two regions is formed.

The forming of the second thin film pattern may include: a) applying a photoresist film on a substrate on which the first thin film pattern and the second thin film are sequentially stacked; b) covering the first thin film pattern and covering the second region. Forming a second photoresist pattern exposing the second thin film corresponding to the non-region, c) etching the second thin film exposed by the second photoresist pattern, and d) forming a second photoresist pattern. It includes the step of removing.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Example 1

1A to 1G are cross-sectional views illustrating a method of manufacturing a monitoring substrate applied to a semiconductor measuring apparatus as a first embodiment of the present invention.

Referring to FIG. 1A, a substrate 100 made of Si and divided into n regions (n is a natural number of two or more) is provided. Here, the substrate is divided into only two regions. The first area has a first area including a center point of the substrate, and the second area has a second area wider than the first area while including the first area of the substrate.

Referring to FIG. 1B, the second thin film 120 and the first thin film 140 are sequentially formed on the front surface of the substrate divided into the first region and the second region to have a uniform thickness. Here, the second thin film 120 and the first thin film 140 may be formed of an insulating material that can transmit light, such as silicon oxide (SiO ₂ ). Is formed. In this case, an etch stop layer (not shown) is further formed between the layers stacked on the substrate, thereby preventing lower layer quality from being etched when the first thin film pattern and the second thin film pattern are formed.

Therefore, the second thin film is the second oxide film 120 and the first thin film is defined as the first oxide film 140. The thickness of the deposited film may be variously adjusted as necessary as the thickness used in the actual process.

1C and 1D, a photoresist film is coated on a surface of a substrate 100 on which the second oxide film 120 and the first oxide film 140 are sequentially stacked to have a uniform thickness. Not). Subsequently, a general photolithography process is performed on the photoresist film to form a first photoresist pattern 150 exposing the first oxide film 140 corresponding to a region other than the first region of the substrate. The first photoresist pattern is a first etching mask pattern.

The first oxide film 140 exposed by the first photoresist pattern 150 is etched to remove the first oxide film pattern 140a on the second oxide film 120 and exists only in the first region. Form.

Referring to FIG. 1E, after removing the first photoresist pattern 150, the photoresist is deposited on the surface of the substrate 100 on which the second oxide film 120 and the first oxide film pattern 140a are sequentially stacked. It is applied to a uniform thickness to form a photoresist film (not shown).

Subsequently, a general photolithography process is performed on the photoresist film to cover the first oxide film pattern 140a and to cover the second oxide film 120 corresponding to a region other than the second region of the substrate including the first region. A second photoresist pattern 160 is formed to be exposed. The second photoresist pattern is a second etching mask pattern.

Although not shown in the drawing, the first oxide film pattern 140a is covered by forming a photoresist film with a uniform thickness without removing the first photoresist pattern, and then performing a conventional photolithography process, wherein The second photoresist pattern 160 exposing the second oxide film 120 corresponding to a region other than the two regions may be formed.

Referring to FIGS. 1F and 1G, the exposed second oxide layer 120 may be covered by covering the first oxide layer pattern 140a and applying a second photoresist pattern 160 having the same size as that of the second region. Etching to form a second oxide film pattern (120a) present in the second region of the substrate (100). In addition, the second photoresist pattern 160 may be removed to form a multi-reference specimen of a semiconductor metrology facility that is applied to inspect the thickness and the contamination state of the semiconductor substrate.

Since the monitoring substrate of the semiconductor metrology facility formed by the above method can form a plurality of films having different thicknesses or types of films on one substrate, various thicknesses of films can be monitored simultaneously.

Example 2

2A to 2I are cross-sectional views illustrating a method of manufacturing a monitoring substrate applied to a semiconductor measuring device as a second embodiment of the present invention.

Referring to FIG. 2A, a semiconductor substrate 100 made of Si and divided into n regions (n is a natural number of 3 or more) is provided. The n areas include a first area, a second area including the first area, a second area wider than the first area, and a second area wider than the second area. Here, the first area has a first area including a center point of the substrate, the second area includes a first area of the substrate and has a second area wider than the first area, and the third area is the second area. It is characterized in that it comprises a region and has a third wider than the second region.

Referring to FIG. 2B, the third thin film 220, the second thin film 240, and the first thin film 260 are uniformly disposed on the entire surface of the substrate 200 divided into the first region, the second region, and the third region. Formed sequentially to have a thickness. The third thin film 220, the second thin film 240, and the first thin film 260 may be formed by using a chemical vapor deposition method, a physical vapor deposition method, or the like. .

The third thin film 220 is an oxide film made of silicon oxide (SiO ₂ ), the second thin film 240 is a nitride film made of silicon nitride (SiN), and the first thin film 260 is made of a conductive material. That's it. In this case, an etch stop layer is further formed between the layers stacked on the substrate to prevent the underlying film from being etched when forming the first thin film pattern, the second thin film pattern, and the third thin film pattern. do.

2C and 2D, an oxide film 220 as a third thin film, a nitride film 240 as a second thin film and a conductive film 260 as a first thin film are sequentially stacked on the surface of the substrate 200. The photoresist is applied to a uniform thickness to form a photoresist film (not shown). Subsequently, a general photolithography process is performed on the photoresist film to form a first photoresist pattern 270 exposing the conductive film 260 corresponding to a region other than the first region. The first photoresist pattern 270 is a first etching mask pattern.

The conductive film 260 exposed by the first photoresist pattern 270 is etched to form a conductive film pattern 260a on the nitride film 240 and existing only in the first region.

Referring to FIG. 2E, after removing the first photoresist pattern 270, the photoresist is uniformly deposited on the surface of the substrate 200 on which the nitride film 240 and the conductive film pattern 260a are sequentially stacked. To form a photoresist film (not shown).

Subsequently, by performing a normal photolithography process on the photoresist film, the second photoport covering the conductive film pattern 260a and exposing the nitride film 240 corresponding to a region other than the second region including the first region is exposed. The resist pattern 280 is formed.

Although not shown in the figure, the conductive film pattern 260a is covered by forming a photoresist film with a uniform thickness thereon, and then performing a conventional photolithography process without removing the first photoresist pattern. A second photoresist pattern 280 exposing the nitride film 240 corresponding to a region other than the region may be formed.

Referring to FIG. 2F, the substrate is formed by etching the exposed nitride layer 240 by covering the conductive layer pattern 260a and applying a second photoresist pattern 280 having the same size as the second region. The nitride film pattern 240a existing in the second region of 200 is formed.

Referring to FIG. 2G, after the second photoresist pattern 280 is removed, the oxide film 220, the nitride film pattern 240a, and the conductive film pattern 260a are sequentially stacked on the surface of the substrate 200. The photoresist is applied to a uniform thickness to form a photoresist film (not shown).

Subsequently, the photoresist film is subjected to a conventional photolithography process to cover the conductive film pattern 260a and the nitride film pattern 240a, and to form an oxide film 220 corresponding to a region other than the third region including the second region. A third photoresist pattern 290 is formed to expose the photoresist.

Although not shown in the figure, the second photoresist pattern is not removed, and the photoresist film is formed thereon with a uniform thickness, and then the conventional photolithography process is performed to cover the conductive film pattern and the nitride film pattern. The third photoresist pattern 290 may be formed to expose the oxide film corresponding to a region other than the region.

2H and 2I, the exposed oxide layer may be covered by covering the conductive layer pattern 260a and the nitride layer pattern 240a and applying a third photoresist pattern 290 having the same size as the third region. The oxide layer pattern 220a existing in the third region of the substrate 200 is formed by etching the 220.

In addition, by removing the third photoresist pattern 290, a monitoring substrate including multiple reference specimens of a semiconductor metrology facility used to inspect the thickness and the contamination state of the semiconductor substrate may be formed.

Since the monitoring substrate formed by the above method can form a plurality of films having different thicknesses or types of films on one substrate, the thickness of each film can be monitored simultaneously.

As described above, according to the present invention, in order to measure the thickness of the thin film and the particles located on the stacked thin films during the manufacturing process of the semiconductor device, different types of multilayer thin films are divided into various regions, and the thicknesses are formed differently in each region. do. As described above, a plurality of regions having different thicknesses and types of thin films stacked on one semiconductor substrate are defined to fabricate a monitoring substrate, and thus, a plurality of reference samples formed on one substrate may be used to cope with a plurality of semiconductor processes.

Therefore, by fabricating a reference sample corresponding to various types of thin films on a single semiconductor substrate, not only the convenience of the process but also the cost required for manufacturing the reference sample can be reduced. That is, the cost of manufacturing the semiconductor device can be reduced by reducing the cost.

As described above, although described with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified without departing from the spirit and scope of the invention described in the claims below. And can be changed.

Claims (9)

(a) providing a substrate divided into n areas (n is a natural number of two or more) including a first area and a second area wider than the first area; (b) sequentially stacking n thin films including a first thin film and a second thin film on the substrate; (c) forming a first thin film pattern present in the first region by etching a first thin film disposed on the second thin film by applying a first etching mask pattern having the same size as the first region; And (d) etching the second thin film on the n thin film by applying a second etching mask pattern covering the first thin film pattern and having the same size as the second region including the first region. Forming a second thin film pattern present in the second region. The method of claim 1, wherein the n thin films comprise different kinds of films. The method of claim 2, wherein when the n thin films are stacked, an etch stop layer is further included between each of the thin films included in the n thin films. The method of claim 1, wherein the forming of the first thin film pattern comprises: Applying a photoresist film on a substrate on which the second thin film and the first thin film are sequentially stacked; Forming a first photoresist pattern exposing a first thin film corresponding to a region other than the first region; And Forming a first thin film pattern on the second thin film by etching the first thin film exposed by the first photoresist pattern. The method of claim 1, wherein the forming of the second thin film pattern comprises: Applying a photoresist film on a substrate on which the second thin film and the first thin film pattern are sequentially stacked; Forming a second photoresist pattern covering the first thin film pattern and exposing a second thin film corresponding to a region other than the second region; And And etching the second thin film exposed by the second photoresist pattern to form the second thin film pattern positioned on the n thin film. The method of claim 5, further comprising removing the second photoresist pattern after the step (d). The method of claim 1, further comprising forming an etching mask pattern and etching the n thin film after the step (d). (a) providing a substrate divided into n areas (n is a natural number of 3 or more) including a first area, a second area wider than the first area, and a third area wider than the second area. ; (b) sequentially stacking n thin films including a first thin film, a second thin film, and a third thin film on the substrate; (c) forming a first thin film pattern present in the first region by applying a first etching mask pattern having the same size as that of the first region to etch one thin film on the second thin film; (d) etching the second thin film on the third thin film by applying a second etching mask pattern covering the first thin film pattern and having the same size as the second area including the first area. Forming a second thin film pattern existing in two regions; And (e) covering the first thin film pattern and the second thin film pattern, and applying a third etching mask pattern having the same size as the third area including the second area to form a third thin film present on the n thin film. Forming a third thin film pattern present in the third region by etching. 8. The method of claim 7, further comprising performing an etching mask pattern and an n thin film after the step (e). 9.