CN113539876B - Method for measuring refractive index of thin film on surface of semiconductor device - Google Patents
Method for measuring refractive index of thin film on surface of semiconductor device Download PDFInfo
- Publication number
- CN113539876B CN113539876B CN202110808669.3A CN202110808669A CN113539876B CN 113539876 B CN113539876 B CN 113539876B CN 202110808669 A CN202110808669 A CN 202110808669A CN 113539876 B CN113539876 B CN 113539876B
- Authority
- CN
- China
- Prior art keywords
- refractive index
- measuring
- thickness
- film layer
- film
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 37
- 239000010409 thin film Substances 0.000 title claims abstract description 28
- 239000004065 semiconductor Substances 0.000 title claims abstract description 14
- 239000010408 film Substances 0.000 claims abstract description 78
- 238000005259 measurement Methods 0.000 claims abstract description 34
- 229910021420 polycrystalline silicon Inorganic materials 0.000 description 10
- 229920005591 polysilicon Polymers 0.000 description 10
- 239000000463 material Substances 0.000 description 7
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 6
- 229910052814 silicon oxide Inorganic materials 0.000 description 6
- 238000000691 measurement method Methods 0.000 description 5
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 3
- 229910052710 silicon Inorganic materials 0.000 description 3
- 239000010703 silicon Substances 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 230000010287 polarization Effects 0.000 description 2
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000007334 copolymerization reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000000623 plasma-assisted chemical vapour deposition Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000002310 reflectometry Methods 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
- H01L22/10—Measuring as part of the manufacturing process
- H01L22/12—Measuring as part of the manufacturing process for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
- H01L22/20—Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Length Measuring Devices By Optical Means (AREA)
Abstract
The invention relates to a measuring method, in particular to a measuring method for the refractive index of a thin film on the surface of a semiconductor device. According to the technical scheme provided by the invention, the method for measuring the refractive index of the thin film on the surface of the semiconductor device comprises the following steps: step 1, measuring by using a film thickness meter to obtain the thickness h1 of a film to be measured, wherein the model refractive index of a measurement model selected in the film thickness meter is n1; step 2, measuring the actual thickness of the film layer to obtain the actual thickness h2 of the film layer; and 3, obtaining the refractive index n2 of the film layer according to the thickness h1, the actual thickness h2 and the model refractive index n1, wherein n2=n1×h1/h2. The invention can effectively realize the measurement of the refractive index of the film, improve the measurement efficiency and reduce the measurement cost.
Description
Technical Field
The invention relates to a measuring method, in particular to a measuring method for the refractive index of a thin film on the surface of a semiconductor device.
Background
In the fabrication of semiconductor devices, it is necessary to deposit different materials on the surface of a semiconductor substrate, some of which have a fixed refractive index, such as silicon oxide. But the refractive index of more materials can fluctuate over a wide range depending on the process, such as silicon nitride, oxygen doped polysilicon, etc.
The change of the refractive index is caused by different preparation processes, so that the monitoring of the refractive index of the film layer is a convenient and better scheme for process adjustment. At present, most of refractive index measurement is carried out by adopting ellipsometer equipment, wherein ellipsometer equipment is equipment for obtaining the refractive index and film thickness of a film layer by adopting light with different polarizations to irradiate the surface of the film and analyzing reflected light.
The measurement of the refractive index is very critical to the regulation of the process, but ellipsometers are very limited in use and not configured by every manufacturer, so that more methods for measuring the refractive index are needed to achieve effective refractive index measurement so as to enable the desired control of the process of the semiconductor device.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provide a method for measuring the refractive index of a film on the surface of a semiconductor device, which can effectively realize the measurement of the refractive index of the film, improve the measurement efficiency and reduce the measurement cost.
According to the technical scheme provided by the invention, the method for measuring the refractive index of the thin film on the surface of the semiconductor device comprises the following steps:
step 1, measuring the thickness h1 of a film layer to be measured by using a film thickness meter, wherein the model refractive index of a measurement model selected in the film thickness meter is n1;
step 2, measuring the actual thickness of the film layer to obtain the actual thickness h2 of the film layer;
and 3, obtaining the refractive index n2 of the film layer according to the thickness h1, the actual thickness h2 and the model refractive index n1, wherein n2=n1×h1/h2.
When the film thickness meter measures the film layer, the light used is monochromatic light or white light.
In the step 1, when the film thickness meter is selected, the difference value between the model refractive index n1 of the measuring model adapted to the film thickness meter and the refractive index n2 of the thin film layer is smaller than 1.5.
In the step 2, when the actual thickness of the film layer is measured, the measuring method comprises an SEM section measuring method, a step meter measuring method or a laser confocal three-dimensional measuring method.
The invention has the advantages that: the thickness h1 of the film layer is measured by using the film thickness meter, the refractive index n2 of the film layer can be obtained by calculating by combining the actual thickness h2 of the film layer and the model refractive index n1 of a measuring model matched with the film thickness meter, so that the measurement of the refractive index of the film can be effectively realized, the measurement efficiency is improved, and the measurement cost is reduced.
Drawings
FIG. 1 is a schematic diagram of the present invention.
Reference numerals illustrate: 1-device unit body and 2-film layer.
Detailed Description
The invention will be further described with reference to the following specific drawings and examples.
In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
As shown in fig. 1: in order to effectively realize the measurement of the refractive index of the film, improve the measurement efficiency and reduce the measurement cost, the measurement method of the invention comprises the following steps:
step 1, measuring the thickness h1 of a film layer 2 to be measured by using a film thickness meter, wherein the model refractive index of a measurement model selected in the film thickness meter is n1;
specifically, the thin film layer 2 to be measured is generally located on the device unit body 1, as shown in fig. 1. The device unit body 1 may be a substrate, etc., and specific forms of the device unit body 1 and the thin film layer 2 may be selected according to actual needs, which will not be described herein.
The film thickness meter is an existing device for measuring the thickness of a certain known material, and can realize the thickness measurement by adopting an optical method. For example, for the model refractive index n1 of known materials, thickness measurement is performed according to measured optical characteristics such as reflectivity, transmissivity and polarization, a plurality of measurement models are stored in a film thickness meter, the thickness of the film layers of the same type can be directly measured according to the selected measurement models, for example, a model of silicon oxide is selected, the refractive index n1 of the measurement model is 1.5, and at the moment, the thickness of various silicon oxide film layers can be obtained by using the film thickness meter. When the film thickness meter measures the film layer 2, the light used is monochromatic light or white light, the specific use of the monochromatic light or the white light can be selected according to actual needs, and the specific use of the film thickness meter for thickness measurement is consistent with the existing mode, which is well known to those skilled in the art and is not described herein.
Step 2, measuring the actual thickness of the film layer 2 to obtain the actual thickness h2 of the film layer 2;
specifically, when the actual thickness measurement is performed on the thin film layer 2, the measurement method includes an SEM section measurement method, a step meter measurement method, or a laser confocal three-dimensional measurement method. The actual thickness process of the thin film layer 2 obtained by specifically measuring by using the SEM section measuring method, the step meter measuring method or the laser confocal three-dimensional measuring method is consistent with the prior art, and is specifically known to those skilled in the art, and is not repeated here.
And 3, obtaining the refractive index n2 of the film layer 2 according to the thickness h1, the actual thickness h2 and the model refractive index n1, wherein n2=n1×h1/h2.
In the embodiment of the present invention, since the thickness of the thin film layer 2 is calculated from the refractive index of the known material by analyzing the reflected light, the measured thickness of the thin film layer 2 is related to the refractive index of the known material, that is, to the model refractive index n 1. In the actual measurement process, the refractive index of the film layer 2 to be measured is different from the model refractive index n1 of the measurement model, so that the thickness of the film layer 2 measured by the film thickness meter is deviated from the actual thickness of the film layer 2, but the refractive index of the film layer 2 is related to the model refractive index n 1. The actual thickness of the thin film layer 2 is obtained by SEM section measurement, step meter measurement, laser copolymerization Jiao Sanwei measurement and the like, so that the refractive index n2 of the thin film layer 2 can be calculated.
In specific implementation, when the film thickness meter is selected, the difference value between the model refractive index n1 of the measuring model adapted to the film thickness meter and the refractive index n2 of the thin film layer 2 is smaller than 1.5. Therefore, when the film thickness meter is used to measure the thin film layer 2, it is necessary to select a corresponding film thickness meter according to the type of material, estimated thickness, and the like of the thin film layer 2, so that the accuracy of measuring the refractive index n2 of the thin film layer 2 can be improved.
The measurement procedure of the present invention will be specifically described by way of specific example 1.
Example 1
And growing 100nm silicon oxide on the surface of the silicon wafer by using a thermal oxidation method, growing a layer of oxygen-doped polysilicon by using a CVD method, and measuring the thickness of the oxygen-doped polysilicon by using a film thickness meter, namely, taking the doped polysilicon as a film layer 2 to be measured. The measuring model of the film thickness meter selects a device unit body 1 with 100nm silicon oxide superimposed on a substrate, a polysilicon film layer is arranged on the silicon oxide, and the thickness of the polysilicon film layer can be accurately measured by using the film thickness meter. The model refractive index n1 of the polysilicon film layer is 3.8. The thickness h1 of the doped polysilicon (i.e., thin film layer 2) was 550nm as measured by a film thickness meter. The actual thickness of the oxygen doped polysilicon (i.e., thin film layer 2) was measured as 680nm using SEM cross-section. Therefore, the refractive index n2 of the oxygen-doped polysilicon was calculated to be 3.07.
Example 2
Growing a layer of Si on the surface of a silicon wafer by using a PECVD method 3 N x I.e. grown Si 3 N x The layer is the thin film layer 2 to be measured. Thickness measurements were made using a film thickness gauge. The measuring model of the film thickness meter is selected from a silicon wafer with Si arranged on the upper surface 3 N 4 A layer. Si (Si) 3 N 4 The layer has a model refractive index n1 of 1.988. Si is measured by a film thickness meter 3 N x The thickness h1 of the layer (i.e. thin film layer 2) was 110nm. Si measurement by step-by-step method 3 N x The actual thickness h2 of the layer (i.e. film layer 2) was 98nm. Thus, si is calculated 3 N x The refractive index n2 of the layer was 2.23.
The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
The above examples illustrate only a few embodiments of the invention, which are described in detail and are not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.
Claims (4)
1. The method for measuring the refractive index of the thin film on the surface of the semiconductor device is characterized by comprising the following steps:
step 1, measuring the thickness h1 of a film layer (2) to be measured by using a film thickness meter, wherein the model refractive index of a measurement model selected in the film thickness meter is n1;
step 2, measuring the actual thickness of the film layer (2) to obtain the actual thickness h2 of the film layer (2);
and step 3, obtaining the refractive index n2 of the film layer (2) according to the thickness h1, the actual thickness h2 and the model refractive index n1, wherein n2=n1×h1/h2.
2. The method for measuring the refractive index of the thin film on the surface of the semiconductor device according to claim 1, wherein the method comprises the following steps: when the film thickness meter measures the film layer (2), the light used is monochromatic light or white light.
3. The method for measuring the refractive index of a thin film on the surface of a semiconductor device according to claim 1 or 2, characterized by: in the step 1, when the film thickness meter is selected, the difference value between the model refractive index n1 of the measuring model adapted to the film thickness meter and the refractive index n2 of the thin film layer (2) is smaller than 1.5.
4. The method for measuring the refractive index of a thin film on the surface of a semiconductor device according to claim 1 or 2, characterized by: in the step 2, when the actual thickness of the film layer (2) is measured, the measuring method comprises an SEM section measuring method, a step-by-step measuring method or a laser confocal three-dimensional measuring method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110808669.3A CN113539876B (en) | 2021-07-16 | 2021-07-16 | Method for measuring refractive index of thin film on surface of semiconductor device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110808669.3A CN113539876B (en) | 2021-07-16 | 2021-07-16 | Method for measuring refractive index of thin film on surface of semiconductor device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113539876A CN113539876A (en) | 2021-10-22 |
| CN113539876B true CN113539876B (en) | 2024-02-13 |
Family
ID=78128489
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110808669.3A Active CN113539876B (en) | 2021-07-16 | 2021-07-16 | Method for measuring refractive index of thin film on surface of semiconductor device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113539876B (en) |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62233755A (en) * | 1986-04-03 | 1987-10-14 | Toyota Motor Corp | Electrostatic capacity type moisture detection sensor |
| JPH04176866A (en) * | 1990-11-08 | 1992-06-24 | Showa Shinku:Kk | Film forming velocity controlling device for sputtering equipment |
| JP2002267835A (en) * | 2001-03-09 | 2002-09-18 | Asahi Optical Co Ltd | Deciding method for refractive index dispersion and deciding method for refractive index distribution |
| JP2004191110A (en) * | 2002-12-10 | 2004-07-08 | Masaru Mitsushio | Refractive index measuring device using gold deposition optical fiber |
| CN101017085A (en) * | 2007-02-27 | 2007-08-15 | 河南中光学集团有限公司 | Method for on-line measuring refractive index of blooming |
| CN101159248A (en) * | 2007-11-16 | 2008-04-09 | 无锡中微晶园电子有限公司 | Method for reducing sub-micron integrate circuit contact hole resistor |
| JP2013121567A (en) * | 2011-12-09 | 2013-06-20 | Konica Minolta Advanced Layers Inc | Method and system for estimating refractive index distribution of thin film |
| CN107121080A (en) * | 2017-06-16 | 2017-09-01 | 东南大学 | A kind of method for measuring ordered porous nano film thickness |
| CN208999296U (en) * | 2018-09-29 | 2019-06-18 | 西安工业大学 | A kind of thin-film optical constant measuring device |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5490462B2 (en) * | 2009-08-17 | 2014-05-14 | 横河電機株式会社 | Film thickness measuring device |
| JP5263460B1 (en) * | 2012-06-12 | 2013-08-14 | 東洋インキＳｃホールディングス株式会社 | Resin composition for light scattering layer, light scattering layer, and organic electroluminescence device |
-
2021
- 2021-07-16 CN CN202110808669.3A patent/CN113539876B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62233755A (en) * | 1986-04-03 | 1987-10-14 | Toyota Motor Corp | Electrostatic capacity type moisture detection sensor |
| JPH04176866A (en) * | 1990-11-08 | 1992-06-24 | Showa Shinku:Kk | Film forming velocity controlling device for sputtering equipment |
| JP2002267835A (en) * | 2001-03-09 | 2002-09-18 | Asahi Optical Co Ltd | Deciding method for refractive index dispersion and deciding method for refractive index distribution |
| JP2004191110A (en) * | 2002-12-10 | 2004-07-08 | Masaru Mitsushio | Refractive index measuring device using gold deposition optical fiber |
| CN101017085A (en) * | 2007-02-27 | 2007-08-15 | 河南中光学集团有限公司 | Method for on-line measuring refractive index of blooming |
| CN101159248A (en) * | 2007-11-16 | 2008-04-09 | 无锡中微晶园电子有限公司 | Method for reducing sub-micron integrate circuit contact hole resistor |
| JP2013121567A (en) * | 2011-12-09 | 2013-06-20 | Konica Minolta Advanced Layers Inc | Method and system for estimating refractive index distribution of thin film |
| CN107121080A (en) * | 2017-06-16 | 2017-09-01 | 东南大学 | A kind of method for measuring ordered porous nano film thickness |
| CN208999296U (en) * | 2018-09-29 | 2019-06-18 | 西安工业大学 | A kind of thin-film optical constant measuring device |
Non-Patent Citations (1)
| Title |
|---|
| 光反射干涉谱新方法测试薄膜厚度和光学常数;廖荣;张海燕;杨铁铮;谈锬;范宇;王道然;;中国测试(第06期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113539876A (en) | 2021-10-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6521470B1 (en) | Method of measuring thickness of epitaxial layer | |
| KR101656436B1 (en) | Method for measuring film thickness distribution of wafer having thin film | |
| JP5660026B2 (en) | Film thickness distribution measurement method | |
| US20090269861A1 (en) | Device and method for manufacturing a semiconductor wafer | |
| CN113539876B (en) | Method for measuring refractive index of thin film on surface of semiconductor device | |
| JP5463905B2 (en) | Epitaxial layer resistivity measurement method | |
| CN109968186A (en) | The online end-point detection method of chemically mechanical polishing based on spectrum | |
| US7861421B2 (en) | Method for measuring rotation angle of bonded wafer | |
| Schoedel et al. | Precise interferometric measurements at single-crystal silicon yielding thermal expansion coefficients from 12 deg to 28 degC and compressibility | |
| CN114029790B (en) | Wafer grinding method | |
| Kuramoto et al. | Density determination of silicon spheres using an interferometer with optical frequency tuning | |
| CN101110379A (en) | Method for measuring silicon slice extension linear defect | |
| US6731386B2 (en) | Measurement technique for ultra-thin oxides | |
| JP2011014800A (en) | Method for measuring film thickness of epitaxial layer, method for manufacturing epitaxial wafer, and method for controlling manufacturing process of epitaxial wafer | |
| JP2002267835A (en) | Deciding method for refractive index dispersion and deciding method for refractive index distribution | |
| US9039907B2 (en) | Methods for improving integrated photonic device uniformity | |
| Hicks et al. | Reflectance modeling for in situ dry etch monitoring of bulk SiO2 and III–V multilayer structures | |
| KR100252749B1 (en) | Method for fabrication of standard wafer used in thickness measurement | |
| CN108180879A (en) | The valued methods and preparation method of ultra-thin silica membrane print | |
| Castelo‐Porta | The future of optical measurement technology: A review of new developments in optical metrology and industry trends in the digitalization and integration of these solutions for in situ and inline measurements | |
| CN118031827A (en) | Correction method of laser ellipsometer | |
| WO2020261745A1 (en) | Semiconductor wafer thickness measurement method and semiconductor wafer thickness measurement system | |
| US20230375460A1 (en) | Epi self-heating sensor tube as in-situ growth rate sensor | |
| CN117889760A (en) | Method, system and storage medium for measuring thickness of epitaxial layer | |
| CN207050670U (en) | A kind of Spectral Confocal measuring system caliberating device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |