KR20090094503A - Thin Film Solar Cell - Google Patents
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- KR20090094503A KR20090094503A KR1020080019478A KR20080019478A KR20090094503A KR 20090094503 A KR20090094503 A KR 20090094503A KR 1020080019478 A KR1020080019478 A KR 1020080019478A KR 20080019478 A KR20080019478 A KR 20080019478A KR 20090094503 A KR20090094503 A KR 20090094503A
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- 239000010409 thin film Substances 0.000 title claims abstract description 25
- 239000000758 substrate Substances 0.000 claims abstract description 18
- 238000005530 etching Methods 0.000 claims abstract description 7
- 239000011521 glass Substances 0.000 claims abstract description 4
- 238000000206 photolithography Methods 0.000 claims abstract description 4
- 230000003287 optical effect Effects 0.000 claims abstract 2
- 238000000034 method Methods 0.000 claims description 18
- 239000010408 film Substances 0.000 claims description 12
- 238000000151 deposition Methods 0.000 claims description 11
- 230000008021 deposition Effects 0.000 description 8
- 238000004519 manufacturing process Methods 0.000 description 7
- 239000004065 semiconductor Substances 0.000 description 7
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 4
- 229920002120 photoresistant polymer Polymers 0.000 description 4
- 229910052710 silicon Inorganic materials 0.000 description 4
- 239000010703 silicon Substances 0.000 description 4
- 229910021417 amorphous silicon Inorganic materials 0.000 description 3
- 230000031700 light absorption Effects 0.000 description 3
- 238000000623 plasma-assisted chemical vapour deposition Methods 0.000 description 3
- 235000012431 wafers Nutrition 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000011368 organic material Substances 0.000 description 2
- 238000007740 vapor deposition Methods 0.000 description 2
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- AMGQUBHHOARCQH-UHFFFAOYSA-N indium;oxotin Chemical compound [In].[Sn]=O AMGQUBHHOARCQH-UHFFFAOYSA-N 0.000 description 1
- 238000012827 research and development 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
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/02—Details
- H01L31/0236—Special surface textures
- H01L31/02366—Special surface textures of the substrate or of a layer on the substrate, e.g. textured ITO/glass substrate or superstrate, textured polymer layer on glass substrate
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
- H01L31/042—PV modules or arrays of single PV cells
- H01L31/0445—PV modules or arrays of single PV cells including thin film solar cells, e.g. single thin film a-Si, CIS or CdTe solar cells
- H01L31/046—PV modules composed of a plurality of thin film solar cells deposited on the same substrate
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
- H01L31/06—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier
- H01L31/075—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier the potential barriers being only of the PIN type
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
Abstract
Description
본 발명은 본 발명은 박막 태양전지 (solar cell) 의 구조 및 그 제조방법에 관한 것으로, 박막 태양전지의 효율을 올리기 위한 것이다.The present invention relates to a structure of a thin film solar cell (solar cell) and a method for manufacturing the same, to increase the efficiency of the thin film solar cell.
태양전지는 태양에너지를 전기에너지로 변환시켜주는 반도체 소자로써 p형의 반도체와 n형의 반도체의 접합형태를 가지며 그 기본구조는 다이오드와 동일하다. 주로 실리콘 단결정 웨이퍼나 다결정 웨이퍼를 이용하는 태양전지가 효율이 높으나 대면적 제조가 용이한 박막형의 태양전지도 제조 및 연구 개발이 진행되고 있다. A solar cell is a semiconductor device that converts solar energy into electrical energy and has a junction type of a p-type semiconductor and an n-type semiconductor. The basic structure is the same as that of a diode. A solar cell mainly using a silicon single crystal wafer or a polycrystalline wafer has a high efficiency, but manufacture and research and development of a thin film solar cell which is easy to manufacture a large area is in progress.
입사된 빛에 의해 전자와 정공들이 생기고 이것이 내부 전기장에 의해 서로 반대 방향으로 움직여 외부로 전류가 흐르게 된다. The incident light creates electrons and holes, which are moved in opposite directions by the internal electric field, causing current to flow outward.
박막형 태양전지의 경우는 기판 위에 반도체 막을 화학 기상 증착법이나 열 증착법, 스파터링 등 여러 가지 방법으로 증착이 되는데 막을 두껍게 증착하기 위해서는 증착 시간이 많이 요구된다. 일반적인 박막형 태양전지의 구조는 도 1과 같으며 투명 기판위에 ITO (indium tin oxide)와 같은 투명전극이 스파터링 등의 증착 장비에서 형성이 되고 이어서 P형 반도체 그리고 흡수층 이어서 N형 반도체 등이 형성되고, 이어서 금속 전극이 스파터링 등의 증착 장비를 이용하여 증착이 된다.In the case of a thin-film solar cell, the semiconductor film is deposited on the substrate by various methods such as chemical vapor deposition, thermal vapor deposition, and spattering. In order to deposit a thick film, much deposition time is required. The structure of a general thin film solar cell is shown in FIG. 1, and a transparent electrode such as indium tin oxide (ITO) is formed on a transparent substrate in a deposition apparatus such as spattering, followed by a P-type semiconductor and an absorption layer, followed by an N-type semiconductor. Subsequently, metal electrodes are deposited using deposition equipment such as spattering.
아모포스 실리콘 박막 태양전지의 경우에는 사일렌(SiH4)개스를 사용하는 PECVD 증착 장비에서, P형의 경우 B2H6 를 혼합 개스로 하여 증착이 되며 N 형 실리콘의 경우 PH3를 혼합 개스로 하여 증착이 된다. In the case of amorphous silicon thin-film solar cell, PECVD deposition equipment using Siylene (SiH 4 ) gas is deposited with mixed gas of B 2 H 6 for P type and mixed gas of PH 3 for N type silicon. Vapor deposition.
이러한 태양전지의 효율은 높을수록 좋으며 태양전지의 효율을 높이기 위한 여러 가지 방법들이 제안되고 있다. The higher the efficiency of the solar cell is better, and various methods have been proposed to increase the efficiency of the solar cell.
박막형 태양전지는 비교적 두꺼운 웨이퍼를 이용하는 태양전지와 달리 막을 증착하여 박막의 형태로 제작이 되기 때문에 막의 두께가 얇아 빛의 흡수가 제한되는 단점이 있다. 이러한 단점을 극복하기 위하여 막의 두께를 증가시키게 되면 막의 증착 시간이 길어지고 공정이 어려워지며 제조 시간이 증가하여 원가 상승의 요인이 되어 바람직하지 않다.Unlike solar cells using relatively thick wafers, thin film type solar cells have a disadvantage in that absorption of light is limited because the thickness of the film is thin because it is manufactured in the form of a thin film. In order to overcome this disadvantage, increasing the thickness of the film is not preferable because the deposition time of the film is long, the process is difficult, and the manufacturing time is increased, causing the cost increase.
본 발명은 이러한 단점을 극복하여 입사된 빛이 막내에서 진행 경로를 증가 시켜 빛의 흡수를 증대시키고 이의 결과로 태양전지의 효율이 증가 되도록 하는 것이다.과제를 해결하기 위한 기본 구조는 기판에 태양전지 박막을 형성하기 전에, 도 2와 같이 요철 면을 구성하여 빛이 입사될 때 막내에서의 빛의 진행 경로가 증가하도록 하여 태양 전지 박막에서 빛이 최대한 많이 흡수될 수 있도록 한다. 도 2의 요철 면에서 수평면과 이루는 경사각이 50도에서 90도 사이가 되도록 하여 태양전지 박막의 증착이 잘 되도록 하면서 태양전지 막 내에서의 빛의 진행 경로를 증가 시키도록 한다. 도 2의 요철 면에서 단면 구조는 사다리꼴이지만 윗 면이 뾰족한 삼각형 구조를 형성 할 수도 있다. 사다리꼴의 윗면이나 삼각형 구조의 윗면은 곡면을 이룰 수도 있다. 이와 같은 곡면은 요철면의 형성 후 추가 에칭으로 각진 부위가 빨리 에칭 되어 만들어 질 수 있고 혹은 열처리에 의한 reflow로 곡면이 형성 될 수도 있다. The present invention overcomes these drawbacks by increasing the propagation path of the incident light in the film to increase the absorption of light and as a result increase the efficiency of the solar cell. Before forming the thin film, a concave-convex surface is formed as shown in FIG. 2 so that the light propagation path in the film increases when light is incident, so that the light can be absorbed as much as possible in the thin film of the solar cell. In the uneven surface of FIG. 2, the inclination angle between the horizontal plane and the horizontal plane is 50 ° to 90 ° so that the solar cell thin film is well deposited while increasing the light propagation path in the solar cell film. In the concave-convex surface of FIG. 2, the cross-sectional structure is trapezoidal, but the upper surface may form a pointed triangular structure. The top of the trapezoid or the top of the triangular structure may be curved. Such a curved surface may be made by quickly etching the angular portion by additional etching after the formation of the uneven surface, or the curved surface may be formed by reflow by heat treatment.
이러한 요철면은 일반적인 사진 식각 공정으로 막을 에칭하여 형성 할 수도 있고 인쇄법으로 요철면을 형성 할 수도 있다. The uneven surface may be formed by etching a film by a general photolithography process, or may be formed by a printing method.
본 발명에 의하여 기판표면의 구조를 형성하고 박막 태양전지를 형성 하면 태양전지를 구성하는 얇은 박막 두께로도 빛의 흡수율을 높이고 태양전지 효율을 올릴 수 있다. According to the present invention, when the structure of the substrate surface is formed and the thin film solar cell is formed, even the thin film thickness constituting the solar cell can increase the light absorption rate and increase the solar cell efficiency.
본 발명에 의한 박막 태양 전지 제작의 일 예로서 일반적인 비정질 실리콘 박막 태양 전지의 제작에 대해서 설명하면 다음과 같다. As an example of fabrication of a thin film solar cell according to the present invention, the fabrication of a typical amorphous silicon thin film solar cell is as follows.
투명 기판인 유리를 표면을 잘 세정 한 다음, 도 3과 같이 표면에 반도체 공정에서 널리 이용되는 사진식각공정법으로서 포토레지스터 패턴을 요철면을 형성하고자 하는 부분에 형성한다. 이 포토레지스터를 마스크로 하여 비등방성 에칭을 실시하여, 도 4와 같이 표면에 요철 면이 형성되도록 하고 이어서 포토레지스터를 제거한다.After cleaning the surface of the glass, which is a transparent substrate, well, a photoresist pattern is formed on the surface to form the uneven surface as a photolithography method widely used in a semiconductor process as shown in FIG. 3. Anisotropic etching is performed using this photoresist as a mask so that an uneven surface is formed on the surface as shown in Fig. 4, and then the photoresist is removed.
이어서 스파터링 등의 장치를 이용하여 ITO 와 같은 투명전극을 도 5와 같이 증착 한다. 이어서 아모포스 실리콘을 증착하기 위하여 PECVD (plasma enhanced chemical vapor deposition) 장치에서 P형 실리콘을 증착하기 위하여 SiH4 기체와 B2H6 기체의 혼합 기체를 이용하여 500 Å 증착한다. Subsequently, a transparent electrode such as ITO is deposited as shown in FIG. 5 using a device such as spattering. Subsequently, in order to deposit P-type silicon in a plasma enhanced chemical vapor deposition (PECVD) apparatus for depositing amorphous silicon, 500 Å deposition is performed using a mixed gas of SiH 4 gas and B 2 H 6 gas.
이어서 SiH4 기체만 사용하여 증착을 하여 도핑이 되지 않은 실리콘 층을 4000 내지 5000 Å 증착을 한다. 이어서 SiH4와 PH3의 혼합 기체를 이용하여 N형 실리콘을 500 Å 증착한다.Subsequently, deposition is performed using only SiH 4 gas to deposit 4000 to 5000 Pa of an undoped silicon layer. Subsequently, 500 N of silicon nitride is deposited using a mixed gas of SiH 4 and PH 3 .
마지막으로 알루미늄과 같은 금속막을 스파터링 등과 같은 증착 장비에서 증착하여 도 6과 같이 본 발명에서 제안하는 태양 전지를 제작할 수 있다.Finally, by depositing a metal film such as aluminum in a deposition apparatus such as spattering, it is possible to manufacture a solar cell proposed in the present invention as shown in FIG.
기판에 요철 면을 형성하는 또 다른 방법으로는 자외선이나 열에 의하여 경화되는 투명 유기 재료들을 인쇄법으로 직접 요철면을 인쇄하는 것이다. 또 다른 방법은 자외선이나 열에 의하여 경화되는 투명 유기 재료를 기판 위에 코팅하고 요철면으로 눌러 요철면을 형성하는 것이다.Another method of forming the uneven surface on the substrate is to directly print the uneven surface by printing transparent organic materials cured by ultraviolet rays or heat. Another method is to coat the transparent organic material cured by ultraviolet rays or heat on the substrate and press the uneven surface to form the uneven surface.
이상과 같이 형성된 태양전지의 입사 빛의 경로의 일예는 도 7에 나타낸 화살표와 같고 본 발명의 태양 구조는 태양 전지 내에서 빛의 경로가 길어져서 태양전지의 효율을 향상 시킬 수 있다. An example of the path of incident light of the solar cell formed as described above is the same as the arrow shown in FIG. 7 and the solar structure of the present invention can improve the efficiency of the solar cell by increasing the path of light in the solar cell.
도1] 일반적인 박막 태양 전지의 단면 구조1] Cross-sectional structure of a general thin film solar cell
도2] 본 발명에 의한 수직 구조의 요철 면2] Uneven surface of the vertical structure according to the present invention
도3] 본 발명의 실시예에 의한 포토레지스터 형성3] photoresist formation according to an embodiment of the present invention
도4] 수직 비등방 에칭 단면Figure 4 Vertical anisotropic etched cross section
도5] 수직 요철 면에 투명전극이 증착 된 단면5] Cross section in which transparent electrode is deposited on vertical uneven surface
도6] 수직 요철 면에 형성된 태양 전지 단면6 is a cross section of a solar cell formed on the vertical uneven surface
도7] 본 발명에 의한 태양 전지에서의 빛의 경로 들Figure 7 Paths of light in the solar cell according to the present invention
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101124490B1 (en) * | 2009-12-15 | 2012-03-16 | (유)에스엔티 | Solar cell and manufacturing method of the same |
| KR101137440B1 (en) * | 2010-04-12 | 2012-04-20 | 삼성코닝정밀소재 주식회사 | Solar Electricity Generation Module using Cover Glass having Patterns for Transmittance Enhancement |
| KR20150004456A (en) * | 2013-07-02 | 2015-01-13 | 성균관대학교산학협력단 | Method for producing solar cell substrate formed concave and convex and solar cell with the same |
| KR101506116B1 (en) * | 2014-05-23 | 2015-03-26 | 성균관대학교산학협력단 | Method of manufacturing patterned glass substrate of solar cell and method of solar cell using thereof |
| KR20210025235A (en) * | 2019-08-27 | 2021-03-09 | 고려대학교 산학협력단 | Solar module |
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2008
- 2008-03-03 KR KR1020080019478A patent/KR20090094503A/en not_active Application Discontinuation
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101124490B1 (en) * | 2009-12-15 | 2012-03-16 | (유)에스엔티 | Solar cell and manufacturing method of the same |
| KR101137440B1 (en) * | 2010-04-12 | 2012-04-20 | 삼성코닝정밀소재 주식회사 | Solar Electricity Generation Module using Cover Glass having Patterns for Transmittance Enhancement |
| KR20150004456A (en) * | 2013-07-02 | 2015-01-13 | 성균관대학교산학협력단 | Method for producing solar cell substrate formed concave and convex and solar cell with the same |
| KR101506116B1 (en) * | 2014-05-23 | 2015-03-26 | 성균관대학교산학협력단 | Method of manufacturing patterned glass substrate of solar cell and method of solar cell using thereof |
| KR20210025235A (en) * | 2019-08-27 | 2021-03-09 | 고려대학교 산학협력단 | Solar module |
| WO2021040211A3 (en) * | 2019-08-27 | 2021-04-29 | 고려대학교 산학협력단 | Solar cell module having excellent visibility |
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