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KR20110025614A - Aluminium paste for a back electrode of solar cell - Google Patents

Aluminium paste for a back electrode of solar cell

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Publication number
KR20110025614A
KR20110025614A KR1020100085604A KR20100085604A KR20110025614A KR 20110025614 A KR20110025614 A KR 20110025614A KR 1020100085604 A KR1020100085604 A KR 1020100085604A KR 20100085604 A KR20100085604 A KR 20100085604A KR 20110025614 A KR20110025614 A KR 20110025614A
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South Korea
Prior art keywords
aluminum
solar cell
paste
glass frit
weight
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KR1020100085604A
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Korean (ko)
Inventor
이창모
이승용
임대성
최형섭
홍승권
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동우 화인켐 주식회사
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Application filed by 동우 화인켐 주식회사 filed Critical 동우 화인켐 주식회사
Priority to JP2012527829A priority Critical patent/JP2013504199A/en
Priority to PCT/KR2010/005998 priority patent/WO2011028058A2/en
Priority to EP10813967.6A priority patent/EP2474040A4/en
Priority to TW099129884A priority patent/TW201133508A/en
Priority to CN2010800426748A priority patent/CN102549760A/en
Publication of KR20110025614A publication Critical patent/KR20110025614A/en

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    • H01B1/00Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
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    • H01B1/22Conductive material dispersed in non-conductive organic material the conductive material comprising metals or alloys
    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03CCHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
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    • C03CCHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
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    • H01L24/04Structure, shape, material or disposition of the bonding areas prior to the connecting process
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    • H01L31/00Semiconductor 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
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    • H01L31/0224Electrodes
    • H01L31/022408Electrodes for devices characterised by at least one potential jump barrier or surface barrier
    • H01L31/022425Electrodes for devices characterised by at least one potential jump barrier or surface barrier for solar cells
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Abstract

PURPOSE: A solar cell battery back side electrode aluminum paste is provided to improve the efficiency of the solar cell battery by improving the contact between the silicon wafer and the aluminum paste. CONSTITUTION: A solar cell battery back side electrode aluminum paste contains the aluminium powder of 65 ~ 75 weight %, the glass frit of 0.01 ~ 5 weight %, and the organic vehicle solution of 20 ~ 34.90 weight %. The aluminium powder has the average particle size distribution of 0.01μm ~ 5μm. The glass frit is the glass frit of Bi2O3-SiO2-Al2O3-B2O3-SrO system.

Description

태양전지의 후면 전극용 알루미늄 페이스트{Aluminium paste for a back electrode of solar cell}Aluminum paste for a back electrode of solar cell

본 발명은 태양전지의 후면 전극용 알루미늄 페이스트에 관한 것이다.The present invention relates to an aluminum paste for a back electrode of a solar cell.

실리콘 결정형 태양전지는 일반적으로 두께가 180-220μm인 P형 실리콘 기판을 사용한다. 상기 기판의 전면부에는 0.2-0.6μm 두께의 n형 불순물층이 형성되고, 그 위에 반사 방지를 위한 SiNx층과 전면 전극이 형성된다. 후면부에는 알루미늄 전극이 형성되는데, 알루미늄 전극은 알루미늄 페이스트를 스크린 인쇄 등에 의해 도포하고 이를 건조한 후, 저온(약 600℃)과 고온(800-950℃)의 2단 소성과정을 거쳐 형성된다. 이러한 소성과정에서 알루미늄이 P형 실리콘 웨이퍼의 내부로 확산되면서 Al-Si 합금층이 형성된다. 이러한 확산층(P+층)에 의해, 태양전지에서 생성되는 전자의 재결합을 방지하고 생성된 캐리어(Carrier)의 수집 효율을 향상시키는 BSF(Back Surface Field)가 형성된다. 이렇게 형성되는 BSF층의 두께 및 균일도에 따라 태양전지의 효율이 좌우되는데 두께가 얇아지면 태양전지의 효율이 저하되고 두꺼워지면 효율이 상승된다. Silicon crystalline solar cells generally use P-type silicon substrates with a thickness of 180-220 μm. An n-type impurity layer having a thickness of 0.2-0.6 μm is formed on the front surface of the substrate, and a SiNx layer and a front electrode are formed thereon to prevent reflection. An aluminum electrode is formed on the rear side. The aluminum electrode is formed by applying an aluminum paste by screen printing and the like and drying it, followed by a two-stage baking process of low temperature (about 600 ° C.) and high temperature (800-950 ° C.). In this firing process, aluminum diffuses into the P-type silicon wafer, thereby forming an Al-Si alloy layer. The diffusion layer (P + layer) forms a back surface field (BSF) that prevents recombination of electrons generated in the solar cell and improves the collection efficiency of the generated carriers. The efficiency of the solar cell depends on the thickness and uniformity of the BSF layer formed as described above. As the thickness becomes thinner, the efficiency of the solar cell decreases and the efficiency increases when the thickness becomes thicker.

한편, 최근 태양전지의 비용절감을 도모하기 위하여 실리콘 웨이퍼의 기판을 얇게 하는 것이 추세인데, 실리콘 웨이퍼의 두께를 얇게 하면 실리콘 웨이퍼와 알루미늄의 팽창계수 차이로 인하여 웨이퍼의 휨이 발생하며, 그에 따라 웨이퍼 갈라짐 등의 현상도 발생된다.On the other hand, in recent years, in order to reduce the cost of solar cells, it is a trend to thin the substrate of the silicon wafer. When the thickness of the silicon wafer is thinned, the warpage of the wafer occurs due to the difference in the expansion coefficient between the silicon wafer and the aluminum, and thus the wafer Phenomena such as cracking also occur.

이러한 문제를 개선하기 위하여, 후면 전극인 알루미늄 전극의 두께를 얇게 형성할 필요가 있으며, 이는 알루미늄 페이스트의 도포량을 줄이는 방법으로 달성될 수 있다. 그러나, 알루미늄 페이스트의 도포량을 줄이게 되면 후면 전계층인 BSF층의 두께가 감소되어 태양전지의 효율이 저하될 뿐만 아니라, 소성공정 중에 전극층에 알루미늄 기포나 범프(Bump)의 발생이 증가하는 문제가 야기된다. 이와 같이 발생된 알루미늄 기포나 돌출부위인 범프(Bump)는 웨이퍼 후면의 평활도를 떨어뜨리며, 그들로 응력이 집중됨에 따라, 태양전지의 제조 공정이나 모듈제조 공정에서 전지의 깨짐을 야기한다. In order to improve this problem, it is necessary to form a thin thickness of the aluminum electrode, which is the rear electrode, which can be achieved by reducing the amount of the aluminum paste applied. However, if the coating amount of aluminum paste is reduced, the thickness of the BSF layer, which is the rear electric field layer, is reduced, which reduces the efficiency of the solar cell, and also causes the problem of the occurrence of aluminum bubbles or bumps in the electrode layer during the firing process. do. The aluminum bubbles or bumps generated as described above lower the smoothness of the back surface of the wafer, and as stress is concentrated thereon, the battery breaks in a solar cell manufacturing process or a module manufacturing process.

소성공정 중에 태양전지의 휨이나 알루미늄 기포의 발생을 감소시키기 위하여 제안된 종래의 기술로는 다음과 같은 것들이 있다. 대한민국 등록특허공보 제10-0825580에는 0.5-10μm 크기의 알루미늄 분말과 유기비히클에 금속알콕사이드를 첨가한 알루미늄 페이스트가 기재되어 있으며, 대한민국 특허공개공보 제10-2008-0068638에는 2-20μm 크기의 알루미늄 분말, 글라스 프릿, 유기 비히클과 더불어 금속 수산화물을 포함하는 알루미늄 페이스트가 기재되어 있으며, 대한민국 특허공개공보 제10-2008-0057230에는 2-20μm 크기의 알루미늄 분말, 글라스 프릿, 유기 비히클과 더불어 가소제를 포함하는 알루미늄 페이스트가 기재되어 있으며, 또한 대한민국 특허공개공보 제10-2008-0104179에는 4-10μm 크기의 알루미늄 입자와 알칼리계 글라스 프릿을 포함하고, 여기에 보론 에톡사이드(Boron Ethoxide), 티타늄 에톡사이드(Titanium Ethoxide), 흄실리카(Fumed silica) 등을 첨가한 알루미늄 페이스트가 기재되어 있다.Conventional techniques proposed to reduce the warpage of the solar cells and the generation of aluminum bubbles during the firing process are as follows. Korean Patent Publication No. 10-0825580 describes aluminum powder having a size of 0.5-10 μm and aluminum paste having metal alkoxide added to an organic vehicle, and Korean Patent Publication No. 10-2008-0068638 describes an aluminum powder having a size of 2-20 μm. And aluminum paste containing metal hydroxides in addition to glass frit and organic vehicle, and Korean Patent Publication No. 10-2008-0057230 includes a plasticizer in addition to aluminum powder, glass frit and organic vehicle having a size of 2-20 μm. Aluminum paste is disclosed, and also Korean Patent Publication No. 10-2008-0104179 includes 4-10 μm of aluminum particles and alkali glass frit, including boron ethoxide and titanium ethoxide. Aluminum paste with Ethoxide, Fumed silica, etc. is described.

그러나 상기 특허문헌들에 소개된 알루미늄 페이스트들은 모두 알루미늄과 글라스 프릿, 유기 비히클 외에 유기 또는 무기 첨가제들을 포함하고 있다. 그런데, 이러한 첨가제들은 페이스트의 소성 과정에서 잔류물로 남거나 공극으로 존재하여 페이스트의 저항을 떨어트릴 뿐만 아니라, 균일도를 저하시켜서 태양전지의 효율에 악영향을 미치는 문제를 야기한다. 또한 상기 알루미늄 페이스트들은 알루미늄 입자의 크기가 최대 10-20μm이기 때문에 텍스쳐링(texturing)된 태양전지의 후면 표면과 균일한 접촉을 형성하기 어려우므로, 내부 기공에 의해 알루미늄 범프(Bump)가 발생될 가능성이 높은 단점을 갖는다.However, the aluminum pastes introduced in the above patent documents all contain organic or inorganic additives in addition to aluminum, glass frit, and organic vehicle. However, these additives remain as residues or voids in the firing process of the paste, which not only lowers the resistance of the paste, but also lowers the uniformity, thereby causing a problem that adversely affects the efficiency of the solar cell. In addition, since the aluminum pastes have a maximum particle size of 10-20 μm, it is difficult to form a uniform contact with the back surface of the textured solar cell, and thus, aluminum bumps may be generated due to internal pores. Has a high disadvantage.

본 발명은, 종래기술의 상기와 같은 문제를 해결하기 위한 것으로서, 소성 공정 중에 태양전지의 휨이나 알루미늄 후면 전극 층에 대한 알루미늄 기포, 범프(Bump) 및 황변의 발생을 최소화하며, Isc 및 Voc 값을 크게 향상시킬 뿐만 아니라, 태양전지의 효율도 획기적으로 향상시키는 태양전지 후면 전극용 알루미늄 페이스트를 제공하는 것을 목적으로 한다.The present invention is to solve the above problems of the prior art, to minimize the generation of aluminum bubbles, bumps and yellowing of the solar cell bending or aluminum back electrode layer during the firing process, Isc and Voc value It is an object of the present invention to provide an aluminum paste for solar cell back electrode that not only greatly improves the efficiency but also significantly improves the efficiency of the solar cell.

조성물 총 중량에 대하여 0.01μm ~ 5μm의 평균입도분포를 갖는 알루미늄 분말 65 ~ 75 중량%; 글라스 프릿 0.1 ~ 5 중량%; 및 유기 비히클 용액 20 ~ 34.90 중량%를 포함하는 태양전지 후면 전극용 알루미늄 페이스트를 제공한다. 65 to 75% by weight of aluminum powder having an average particle size distribution of 0.01 μm to 5 μm relative to the total weight of the composition; 0.1-5% by weight of glass frit; And 20 to 34.90 wt% of an organic vehicle solution.

또한, 본 발명은 In addition,

상기의 알루미늄 페이스트를 사용하여 후면 전극을 형성하는 공정을 포함하는 것을 특징으로 하는 태양전지의 제조방법을 제공한다.It provides a solar cell manufacturing method comprising the step of forming a back electrode using the aluminum paste.

본 발명은 알루미늄 페이스트 조성물은 텍스쳐링되어 있는 실리콘 웨이퍼와 알루미늄 페이스트 간의 접촉을 향상시킴으로써 소성 공정 중에 태양전지의 휨이나 알루미늄 후면 전극 층에 대한 알루미늄 기포, 범프(Bump) 및 황변의 발생을 최소화하며, Isc 및 Voc 값을 크게 향상시킬 뿐만 아니라, 태양전지의 효율도 획기적으로 향상시킨다.According to the present invention, the aluminum paste composition improves contact between the textured silicon wafer and the aluminum paste, thereby minimizing the generation of aluminum bubbles, bumps and yellowing of the solar cell during the firing process or the aluminum back electrode layer, and isc. And not only greatly improve the Voc value, but also dramatically improve the efficiency of the solar cell.

본 발명은 조성물 총 중량에 대하여 0.01μm ~ 5μm의 평균입도분포를 갖는 알루미늄 분말 65 ~ 75 중량%; 글라스 프릿 0.01 ~ 5 중량%; 및 유기 비히클 용액 20 ~ 34.90 중량% 를 포함하는 태양전지 후면 전극용 알루미늄 페이스트에 관한 것이다.The present invention is 65 to 75% by weight aluminum powder having an average particle size distribution of 0.01μm to 5μm relative to the total weight of the composition; 0.01-5% by weight of glass frit; And 20 to 34.90 wt% of an organic vehicle solution.

본 발명의 페이스트 조성물에 포함되는 알루미늄 분말은 평균입도분포가 0.01μm-5μm인 것을 사용한다. The aluminum powder contained in the paste composition of the present invention uses an average particle size distribution of 0.01 μm-5 μm.

일반적으로 실리콘 태양전지의 경우 태양빛의 수광면적을 넓히기 위하여 앞뒤 표면을 텍스쳐링(texturing) 하게 된다. 일반적으로 단결정 텍스쳐링의 형태는 피라미드 형태의 구조를 갖게 되는데 이러한 피라미드 구조의 높이는 2 μm~15μm / 폭은 2μm~20μm 내외로 형성된다. 또한 다결정 실리콘 텍스쳐링은 불규칙한 미로형태를 갖게 된다. 이러한 구조를 가지는 실리콘 웨이퍼상에 알루미늄 페이스트를 스크린 인쇄, 그라비아 인쇄 또는 옵셋인쇄를 통해 후면 알루미늄 페이스트를 인쇄하고 건조한 후, 소성 공정을 거쳐 알루미늄 전극을 형성하게 된다. 이러한 공정에서 알루미늄 입자의 크기가 너무 크게 되면 알루미늄 페이스트와 실리콘 웨이퍼와의 접촉이 잘 이루어지지 않고, 인쇄 및 건조 후에 페이스트와 실리콘 웨이퍼의 텍스쳐 구조 사이에 공극이 형성되게 된다. 이러한 공극은 소성과정을 진행하는 동안 알루미늄 페이스트층을 통과하여 알루미늄 전극 표면으로 분출되는데, 이러한 과정과 동반하여 알루미늄의 범프(bump)와 기포가 발생하게 된다. 따라서 페이스트에 포함되는 알루미늄 분말의 평균입도분포는 0.01μm ~ 5μm의 범위가 바람직하다. 평균입도가 0.01μm 미만인 경우에는 인쇄 후 소성공정에서 알루미늄 범프가 발생하고, 웨이퍼 휨이 커지는 문제가 있고, 5μm를 초과하는 경우에는 입자의 충진율이 떨어고, 이로 인해 효율이 저하되는 문제가 발생된다In general, in the case of silicon solar cells, the front and rear surfaces are textured to broaden the light receiving area of sunlight. In general, the form of single crystal texturing has a pyramidal structure, and the height of the pyramid structure is about 2 μm to 15 μm and the width is about 2 μm to 20 μm. In addition, polycrystalline silicon texturing has an irregular maze shape. The aluminum paste is printed on the silicon wafer having the above structure by screen printing, gravure printing, or offset printing, and dried, and then the aluminum electrode is formed through a firing process. In this process, if the size of the aluminum particles is too large, the contact between the aluminum paste and the silicon wafer is poor, and voids are formed between the paste and the texture structure of the silicon wafer after printing and drying. These pores are ejected through the aluminum paste layer to the surface of the aluminum electrode during the firing process, and bumps and bubbles of aluminum are generated along with this process. Therefore, the average particle size distribution of the aluminum powder included in the paste is preferably in the range of 0.01 μm to 5 μm. If the average particle size is less than 0.01 μm, aluminum bumps are generated in the post-printing firing process, and wafer warpage is increased. If the average particle size is larger than 5 μm, the filling rate of the particles is lowered, which causes a problem of lowering the efficiency.

상기와 같은 평균입도분포를 갖는 알루미늄 분말을 사용하여 페이스트를 제조하게 되면, 웨이퍼의 텍스쳐링 구조사이에 깊숙이 페이스트가 침투할 수 있을 뿐만 아니라 페이스트 내의 공극률도 감소된다. 따라서, 후면 BSF층이 균일하게 형성되고 알루미늄 전극의 저항도 낮아지며, 웨이퍼의 휨도 억제된다. 그러므로, 상기와 같은 알루미늄 분말을 사용하여 제조되는 태양전지는 최대출력전류(Isc)가 상승되고 효율도 증가된다. 또한, 소성공정 후 알루미늄 전극에서 발생하는 황변 현상이 방지되는 효과도 얻을 수 있다.When the paste is manufactured using the aluminum powder having the average particle size distribution as described above, the paste can penetrate deeply between the texturing structures of the wafer and the porosity in the paste is also reduced. Therefore, the back side BSF layer is formed uniformly, the resistance of the aluminum electrode is also lowered, and the warping of the wafer is also suppressed. Therefore, in the solar cell manufactured using the aluminum powder as described above, the maximum output current Isc is increased and the efficiency is also increased. In addition, it is also possible to obtain an effect of preventing the yellowing phenomenon occurring in the aluminum electrode after the firing process.

또한, 본 발명의 페이스트 조성물에 있어서, 알루미늄 분말은 입도분포가 0.01μm-5μm로 한정된 것이 사용될 수도 있다. In addition, in the paste composition of the present invention, the aluminum powder may be one whose particle size distribution is limited to 0.01 μm-5 μm.

본 발명의 알루미늄 페이스트에 있어서 상기 알루미늄 분말은 65 ~ 75 중량%로 포함되는 것이 바람직하며, 65 중량% 미만으로 포함되면 소성 후 인쇄된 알루미늄 층이 얇아져 후면 BSF층이 충분히 형성되지 않아 효율이 떨어지는 문제가 발생하며, 75 중량%를 초과하면 인쇄층이 너무 두꺼워지고 이로 인해 실리콘 웨이퍼의 휨이 초래될 수 있다.
In the aluminum paste of the present invention, the aluminum powder is preferably contained in 65 to 75% by weight, and if it is included in less than 65% by weight, the printed aluminum layer becomes thinner after firing, so that the rear BSF layer is not sufficiently formed so that efficiency is low. If it exceeds 75% by weight, the printed layer becomes too thick, which may result in warping of the silicon wafer.

본 발명의 페이스트 조성물에 포함되는 글라스 프릿은 0.01-5 중량%, 바람직하게는 0.05-3 중량%, 더욱 바람직하게는 0.1-1 중량%로 포함된다. Glass frit included in the paste composition of the present invention is contained in 0.01-5% by weight, preferably 0.05-3% by weight, more preferably 0.1-1% by weight.

상기 글라스 프릿으로는 예컨대, Bi2O3-Al2O3-SiO2-SrO-B2O3계를 들 수 있다. 상기 글라스 프릿의 조성비는 특별히 한정되는 것은 아니지만 Bi2O3 20-30mol%, Al2O3 5-15mol%, SiO2 25-35mol%, SrO 1-10mol% 및 B2O3 20-40mol%를 포함하는 조성을 갖는 것이 바람직하다. Examples of the glass frit include a Bi 2 O 3 -Al 2 O 3 -SiO 2 -SrO-B 2 O 3 system. Although the composition ratio of the glass frit is not particularly limited, 20-30 mol% of Bi 2 O 3, 5-15 mol% of Al 2 O 3, 25-35 mol% of SiO 2, 1-10 mol% of SrO, and 20-40 mol% of B 2 O 3 It is preferable to have a composition containing.

상기 글리스 프릿 조성에서 SrO는 글라스 프릿의 연화점을 낮추는데 효과적이다. SrO가 포함되지 않은 조성에서는 글라스 프릿의 연화점이 높아져서 태양전지 소성공정에서 페이스트가 제대로 연화되지 않으므로 실리콘 웨이퍼와의 밀착력이 떨어져 효율저하가 초래된다. 그러나, SrO가 과량으로 포함되는 경우에는 연화점이 너무 낮아져 알루미늄 전극에서 Bump의 발생이 초래된다. SrO is effective in lowering the softening point of the glass frit. If the composition does not contain SrO, the softening point of the glass frit is increased, so that the paste does not soften properly in the solar cell firing process, resulting in poor adhesion to the silicon wafer, resulting in reduced efficiency. However, when SrO is included in excess, the softening point is too low, resulting in the generation of bumps in the aluminum electrode.

또한, 본 발명에서 사용되는 글라스 프릿은 연화점이 400~600℃인 것이 바람직하다. 글라스 프릿의 연화점이 400℃ 미만인 경우에는 글라스 프릿의 열팽창계수가 상대적으로 커져 이로 인해 태양전지 제조 공정 중 소성공정을 거친 후 웨이퍼의 휨을 증가시키는 문제가 발생하며, 600℃를 초과하는 경우에는 소성과정에서 글라스 프릿이 용융되어 알루미늄 층과 실리콘웨이퍼층 사이에서 밀착성을 부여해야 되는데 글라스 프릿이 충분히 용융되지 않아 밀착성이 저하되는 문제가 발생할 수 있다.
Moreover, it is preferable that the softening point of the glass frit used by this invention is 400-600 degreeC. If the softening point of the glass frit is less than 400 ℃, the coefficient of thermal expansion of the glass frit is relatively large, which causes a problem of increasing the warpage of the wafer after the firing process during the solar cell manufacturing process. In the glass frit is melted to give adhesion between the aluminum layer and the silicon wafer layer, but the glass frit is not sufficiently melted may cause a problem that the adhesion is reduced.

본 발명의 페이스트는 조성물 총 중량에 대하여 20~34.90 중량%의 유기 비히클 용액을 포함하는 것이 바람직하며, 상기 유기 비히클 용액은 유기용매에 고분자 수지를 녹여서 제조하며, 필요에 따라, 요변성제, 습윤제, 첨가제 등을 포함할 수 있다.The paste of the present invention preferably comprises an organic vehicle solution of 20 to 34.90% by weight based on the total weight of the composition, the organic vehicle solution is prepared by dissolving a polymer resin in an organic solvent, if necessary, thixotropic agents, wetting agents, Additives and the like.

본 발명에 사용되는 유기 비히클 용액은 용액 총 중량에 대하여, 75 중량% 이상의 용매, 1-30 중량%의 고분자 수지, 약 5 중량% 이하의 습윤제와 요변성제, 및 1~10 중량%의 첨가제를 포함할 수 있다. The organic vehicle solution used in the present invention may contain at least 75% by weight of solvent, 1-30% by weight of polymer resin, up to about 5% by weight of wetting agent and thixotropic agent, and 1-10% by weight of the additive based on the total weight of the solution. It may include.

상기 용매로는 인쇄공정 중 페이스트의 건조를 막고 유동성을 조절할 수 있도록 약 150-300℃ 범위의 끊는점을 갖는 용매가 적합하다. 널리 사용되는 용매로는 글리콜 에테르 계열로 트리프로필렌글리콜 메틸에테르, 디프로필렌글리콜 n-프로필에테르, 디프로필렌글리콜 n-부틸에테르, 트리프로필렌글리콜 n-부틸에테르, 프로필렌글리콜 페닐에테르, 디에틸렌글리콜 에틸에테르, 디에틸렌글리콜 n-부틸에테르, 디에틸렌글리콜 헥실에테르, 에틸렌글리콜 헥실에테르, 트리에틸렌글리콜 메틸에테르, 트리에틸렌글리콜 에틸에테르, 트리에틸렌글리콜 n-부틸에테르, 에틸렌글리콜 페닐에테르, 터피놀, Texanol® 에틸렌글리콜 등을 들 수 있다.As the solvent, a solvent having a breaking point in the range of about 150-300 ° C. is suitable to prevent drying of the paste during the printing process and to control fluidity. Widely used solvents include glycol ether-based tripropylene glycol methyl ether, dipropylene glycol n-propyl ether, dipropylene glycol n-butyl ether, tripropylene glycol n-butyl ether, propylene glycol phenyl ether, diethylene glycol ethyl ether. , Diethylene glycol n-butyl ether, diethylene glycol hexyl ether, ethylene glycol hexyl ether, triethylene glycol methyl ether, triethylene glycol ethyl ether, triethylene glycol n-butyl ether, ethylene glycol phenyl ether, terpinol, Texanol ® Ethylene glycol etc. are mentioned.

상기 고분자 수지로는 폴리비닐피롤리돈, 폴리비닐알코올, 폴리에틸렌글리콜, 에틸셀룰로오스, 로진, 페놀 수지, 아크릴 수지 등을 들 수 있다. 고분자 수지의 함량은 유기 비히클 용액 총 중량에 대하여 1-30 중량%, 바람직하게는 5-25 중량%가 좋다. 고분자수지의 첨가량이 1 중량% 미만일 경우 페이스트의 인쇄성 및 분산 안정성이 저하되고, 30 중량%를 초과할 경우에는 페이스트가 인쇄되지 않는 문제를 초래 할 수 있다.Examples of the polymer resin include polyvinylpyrrolidone, polyvinyl alcohol, polyethylene glycol, ethyl cellulose, rosin, phenol resin, acrylic resin and the like. The content of the polymer resin is preferably 1-30% by weight, preferably 5-25% by weight based on the total weight of the organic vehicle solution. If the amount of the polymer resin is less than 1% by weight, the printability and dispersion stability of the paste may be lowered. If the amount of the polymer resin is more than 30% by weight, the paste may not be printed.

상기 요변성제 및 습윤제로는 이 분야에서 일반적으로 사용되는 것을 제한 없이 사용할 수 있다.As the thixotropic agent and the humectant, any one generally used in the art may be used without limitation.

상기 첨가제로는 분산제 등 이 분야에서 일반적으로 사용되는 것을 들 수 있다. 상기 분산제로는 시판되는 계면 활성제를 이용할 수 있고, 이들은 각각 단독으로 또는 2종 이상을 조합하여 사용할 수 있다. 상기의 계면 활성제는, 예를 들면, 비이온성 계면활성제로서 알킬 폴리옥시에틸렌에테르, 알킬아릴 폴리옥시에틸렌에테르, 폴리옥시에틸렌 폴리옥시프로필렌 공중합체와 같은 에테르형; 글리세린에스테르의 폴리옥시에틸렌에테르, 솔비탄 에스테르의 폴리옥시에틸렌에테르, 솔비톨 에스테르의 폴리옥시에틸렌에테르 같은 에스테르에테르형; 폴리에틸렌글리콜지방산에스테르, 글리세린에스테르, 솔비탄에스테르, 프로필렌글리콜에스테르, 슈가에스테르, 알킬폴리글루코시드 같은 에스테르형; 지방산알카놀아미드, 폴리옥시에틸렌지방산아미드, 폴리옥시에틸렌알킬아민, 아민 옥사이드 같은 함질소형이 있으며; 고분자계 계면활성제로서 폴리비닐알콜, 폴리비닐피롤리돈, 폴리아크릴산, 폴리아크릴산-말레인산 공중합체, 폴리 12-히드록시스테아린산 등이 있다.The additives include those generally used in this field such as dispersants. Commercially available surfactants can be used as the dispersant, and these can be used alone or in combination of two or more thereof. The surfactant may be, for example, an ether type such as alkyl polyoxyethylene ether, alkylaryl polyoxyethylene ether, polyoxyethylene polyoxypropylene copolymer as a nonionic surfactant; Ester ether types such as polyoxyethylene ether of glycerin ester, polyoxyethylene ether of sorbitan ester, and polyoxyethylene ether of sorbitol ester; Ester type such as polyethylene glycol fatty acid ester, glycerin ester, sorbitan ester, propylene glycol ester, sugar ester, alkyl polyglucoside; Nitrogen-containing types such as fatty acid alkanolamides, polyoxyethylene fatty acid amides, polyoxyethylene alkylamines, amine oxides; Polymeric surfactants include polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acid, polyacrylic acid-maleic acid copolymers, poly 12-hydroxystearic acid, and the like.

시판되는 상품으로는 하이퍼머(hypermer) KD(Uniqema 제조), AKM 0531(일본유지㈜ 제조), KP(신에쯔 가가꾸 고교㈜ 제조), 폴리플로우(POLYFLOW)(교에이샤 가가꾸㈜ 제조), 에프톱(EFTOP)(토켐 프로덕츠사 제조), 아사히가드(Asahi guard), 서플론(Surflon)(이상, 아사히 글라스㈜ 제조), 솔스퍼스(SOLSPERSE)(제네까㈜ 제조), EFKA(EFKA 케미칼스사 제조), PB 821(아지노모또㈜ 제조), BYK-184, BYK-185, BYK-2160, Anti-Terra U(BYK사 제조) 등을 들 수 있다. Commercially available products include Hypermer KD (manufactured by Uniqema), AKM 0531 (manufactured by Nippon Yuji Co., Ltd.), KP (manufactured by Shin-Etsu Chemical Co., Ltd.), and POLYFLOW (manufactured by Kyowa Co., Ltd.). ), EFTOP (manufactured by Tochem Products), Asahi guard, Suflon (above, manufactured by Asahi Glass), SOLSPERSE (manufactured by Geneva), EFKA (EFKA) Chemicals Co., Ltd.), PB 821 (made by Ajinomoto Co., Ltd.), BYK-184, BYK-185, BYK-2160, Anti-Terra U (by BYK Co., Ltd.), etc. are mentioned.

상기 분산제는 유기 비히클 용액 총 중량에 대하여 1~10중량%이 바람직하며, 더욱 바람직하게는 1~5중량%가 좋다.
The dispersant is preferably 1 to 10% by weight, more preferably 1 to 5% by weight based on the total weight of the organic vehicle solution.

본 발명에 따른 페이스트 제조는 자전과 공전을 동시에 수행하는 플래너리 믹서를 이용하여 쉽게 제조될 수 있다. 즉, 상기에서 언급된 성분들을 해당 조성비에 따라 플래너리 믹서 용기에 넣고 교반을 실시하여 고형분과 유기 비히클 용액을 적절히 혼합 및 분산키켜 제조 할 수 있다. 이렇게 제조된 페이스트의 점도는 25℃에서 부룩필드(Brookfield) HBDV-III Ultra Rheometer, 스핀들 CPE-52로 측정했을 때, 5rpm에서 20,000~200,000cps이다. 바람직하게는 40,000~100,000cps 범위로 제조되는 것이 좋다.
Paste preparation according to the present invention can be easily produced using a planetary mixer that performs both rotation and revolution at the same time. That is, the above-mentioned components may be prepared by mixing and dispersing the solid content and the organic vehicle solution appropriately by putting the above-mentioned components into the planetary mixer container according to the corresponding composition ratio and stirring. The viscosity of the paste thus prepared was 20,000-200,000 cps at 5 rpm as measured by a Brookfield HBDV-III Ultra Rheometer, spindle CPE-52 at 25 ° C. Preferably it is preferably produced in the range of 40,000 ~ 100,000cps.

또한, 본 발명은In addition,

상기 알루미늄 페이스트를 사용하여 후면 전극을 형성하는 공정을 포함하는 것을 특징으로 하는 태양전지의 제조방법을 제공한다.It provides a method of manufacturing a solar cell comprising the step of forming a back electrode using the aluminum paste.

상기 방법에 의하여 제조된 태양전지는 휨이나 전극 층에 알루미늄 기포 및 범프(Bump)의 발생이 최소화되어, Isc 및 Voc 값이 향상될 뿐만 아니라 태양전지의 효율도 획기적으로 향상된다.
The solar cell manufactured by the above method minimizes the occurrence of warpage or aluminum bubbles and bumps in the electrode layer, thereby improving the Isc and Voc values as well as dramatically improving the efficiency of the solar cell.

이하에서, 실시예를 통하여 본 발명을 보다 상세히 설명한다. 그러나, 하기의 실시예는 본 발명을 더욱 구체적으로 설명하기 위한 것으로서, 본 발명의 범위가 하기의 실시예에 의하여 한정되는 것은 아니다. 하기의 실시예는 본 발명의 범위 내에서 당업자에 의해 적절히 수정, 변경될 수 있다.
Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following examples are intended to illustrate the present invention more specifically, but the scope of the present invention is not limited by the following examples. The following examples can be appropriately modified and changed by those skilled in the art within the scope of the present invention.

실시예1: 알루미늄 페이스트의 제조Example 1 Preparation of Aluminum Paste

평균입도분포가 0.04 ~ 5μm인 알루미늄 분말 70 중량%, 하기 표 1의 조성의 글라스 프릿 0.5 중량%, 에틸셀룰로오스를 글리콜 에테르에 녹여 용해시킨 유기 비히클 용액 29.5 중량%를 순차적으로 첨가 한 후, 자전 및 공전을 동시에 수행하는 믹서를 이용하여 1,000rpm에서 3분간 교반을 실시하여 알루미늄 페이스트를 제조하였다. 70 weight% of aluminum powder having an average particle size distribution of 0.04 to 5 μm, 0.5 weight% of glass frit having the composition shown in Table 1 below, and 29.5 weight% of an organic vehicle solution in which ethyl cellulose was dissolved and dissolved in glycol ether, followed by rotating and An aluminum paste was prepared by stirring at 1,000 rpm for 3 minutes using a mixer that simultaneously performs revolution.

Mol%Mol% Mol%Mol% Al2O3 Al 2 O 3 6.5%6.5% SrOSrO 5.5%5.5% Bi2O3 Bi 2 O 3 26.0%26.0% B2O3 B 2 O 3 30.0%30.0% SiO2 SiO 2 32.0%32.0% Tg (전이점)Tg (transition point) 453453 열팽창계수 (10-7/℃)Thermal expansion coefficient (10 -7 / ℃) 7777 TdspTdsp 507507

실시예2: 알루미늄 페이스트의 제조Example 2 Preparation of Aluminum Paste

평균입도분포가 0.04 ~ 5μm인 알루미늄 분말을 65 중량%의 함량으로 넣고, 유기 비히클 용액을 34.5 중량%로 첨가한 것을 제외하고는 실시예 1과 동일한 방법으로 알루미늄 페이스트를 제조하였다.
An aluminum paste was prepared in the same manner as in Example 1, except that an aluminum powder having an average particle size distribution of 0.04 to 5 μm was added at a content of 65 wt% and an organic vehicle solution was added at 34.5 wt%.

실시예3: 알루미늄 페이스트의 제조Example 3 Preparation of Aluminum Paste

평균입도분포가 0.04 ~ 5μm인 알루미늄 분말을 75 중량%의 함량으로 넣고, 유기 비히클 용액을 24.5 중량%로 첨가한 것을 제외하고는 실시예 1과 동일한 방법으로 알루미늄 페이스트를 제조하였다.
An aluminum paste was prepared in the same manner as in Example 1, except that an aluminum powder having an average particle size distribution of 0.04 to 5 μm was added in a content of 75 wt% and an organic vehicle solution was added at 24.5 wt%.

비교예1: 알루미늄 페이스트의 제조Comparative Example 1: Preparation of Aluminum Paste

글라스 프릿을 하기 표2의 조성으로 대체하는 것을 제외하고는 실시예 1과 동일한 방법으로 알루미늄 페이스트를 제조하였다. An aluminum paste was prepared in the same manner as in Example 1 except that the glass frit was replaced with the composition shown in Table 2 below.

Mol%Mol% Mol%Mol% Al2O3 Al 2 O 3 10.91%10.91% SrOSrO -- Bi2O3 Bi 2 O 3 12.94%12.94% B2O3 B 2 O 3 46.93%46.93% SiO2 SiO 2 28.61%28.61% Tg (전이점)Tg (transition point) 473473 열팽창계수 (10-7/℃)Thermal expansion coefficient (10 -7 / ℃) 7373 TdspTdsp 523523

비교예2: 알루미늄 페이스트의 제조Comparative Example 2: Preparation of Aluminum Paste

평균입도분포가 0.04 ~ 5μm인 알루미늄 분말을 76 중량%의 함량으로 넣고, 유기 비히클 용액을 23.5 중량%로 첨가한 것을 제외하고는 실시예 1과 동일한 방법으로 알루미늄 페이스트를 제조하였다.
An aluminum paste was prepared in the same manner as in Example 1, except that an aluminum powder having an average particle size distribution of 0.04 to 5 μm was added in a content of 76 wt% and an organic vehicle solution was added at 23.5 wt%.

비교예3: 알루미늄 페이스트의 제조Comparative Example 3: Preparation of Aluminum Paste

평균입도분포가 0.04 ~ 5μm인 알루미늄 분말 대신 2 ~ 10μm인 알루미늄 분말을 사용한 것을 제외하고는 실시예 1과 동일한 방법으로 알루미늄 페이스트를 제조하였다.
An aluminum paste was prepared in the same manner as in Example 1 except that an aluminum powder having an average particle size distribution of 2 to 10 μm was used instead of an aluminum powder having an average particle size of 0.04 to 5 μm.

비교예4: 알루미늄 페이스트의 제조Comparative Example 4: Preparation of Aluminum Paste

평균입도분포가 0.04 ~ 5μm인 알루미늄 분말 대신 5 ~ 15μm인 알루미늄분말을 사용한 것을 제외하고는 실시예 1과 동일한 방법으로 알루미늄 페이스트를 제조하였다.
An aluminum paste was prepared in the same manner as in Example 1, except that an aluminum powder having 5 to 15 μm was used instead of an aluminum powder having an average particle size distribution of 0.04 to 5 μm.

시험예: 태양전지의 제조 및 특성 테스트Test Example: Manufacturing and Characteristic Test of Solar Cell

156X156mm, 200μm 두께의 단결정 웨이퍼에 표면 텍스쳐링 공정을 수행하여 피라미드 높이가 약 4-6μm로 형성된 후, 웨이퍼의 N-측 상에 SiNx를 코팅하였다. 이어서, 웨이퍼의 후면에 은-페이스트를 이용하여 Bus Bar를 인쇄하여 건조시킨 후, 상기 실시예1~3 및 비교예1~4의 페이스트를 250mesh의 스크린 인쇄판을 이용하여 페이스트의 중량이 1.5±0.1g이 되게 도포하고 건조 시켰다. 전면 SiNx측 상에 은-페이스트를 이용하여 Finger Line을 인쇄하고 건조하였다.A surface texturing process was performed on a 156 × 156 mm, 200 μm thick single crystal wafer to form a pyramid height of about 4-6 μm, followed by coating SiNx on the N-side of the wafer. Subsequently, the Bus Bar was printed and dried on the back surface of the wafer using silver paste, and then the pastes of Examples 1 to 3 and Comparative Examples 1 to 4 were coated using a 250-mesh screen printing plate to have a paste weight of 1.5 ± 0.1. It was applied to g and dried. Finger lines were printed and dried using silver paste on the front SiNx side.

상기 과정을 거친 실리콘 웨이퍼를 적외선 연속 소성로에서 소성영역의 온도가 720 - 900℃가 되도록 하여 소성하여 태양전지를 제조하였다.The silicon wafer passed through the above process was fired in an infrared continuous firing furnace such that the temperature of the firing region was 720-900 ° C to manufacture a solar cell.

상기 소성공정은 상기 실리콘 웨이퍼를 벨트 로(Belt Furnace) 내로 통과 시키면서 전후면 동시 소성으로 수행될 수도 있다. 이때, 벨트 로(Belt Furnace)는 약 600℃의 Burn-out 구간과 800~950℃ 부근의 Firing 구간을 포함하며, 페이스트 내 유기물을 태워 없앤 후, 전후면 은과 알루미늄을 용융시켜서 전극이 형성되게 한다.The firing process may be performed by simultaneous firing of the front and rear surfaces while passing the silicon wafer into a belt furnace. At this time, the belt furnace includes a burn-out section of about 600 ° C. and a firing section around 800 ° C. to 950 ° C., and burns away the organic material in the paste, and then melts the silver and aluminum on the front and rear surfaces to form an electrode. do.

상기에서 제조된 태양전지의 네모서리를 바닥과 일치시킨 후, 중앙부의 들뜸정도를 측정하여 태양전지의 휘어짐 정도를 평가하였다. 또한, 후면 알루미늄 전극 부위의 범프(Bump) 및 알루미늄 기포의 발생은 육안으로 관찰하여 개수를 카운트 하였다. 평가 결과는 하기 표 3에 나타내었다.After matching the four corners of the solar cell manufactured above with the bottom, the degree of lifting of the center portion was measured to evaluate the degree of warpage of the solar cell. In addition, the occurrence of bumps and aluminum bubbles in the rear aluminum electrode region was visually observed and the number was counted. The evaluation results are shown in Table 3 below.

태양전지의 효율은 FitTech사의 태양전지 성능 평가 장치인 SCM-1000을 이용하여 평가하고, 그 결과를 하기 표 4에 나타내었다.The efficiency of the solar cell was evaluated using SCM-1000, a solar cell performance evaluation device of FitTech, and the results are shown in Table 4 below.

실시예 1Example 1 실시예 2Example 2 실시예 3Example 3 비교예 1Comparative Example 1 비교예 2Comparative Example 2 비교예 3Comparative Example 3 비교예 4Comparative Example 4 Al 분말Al powder 0.04-5μm0.04-5μm 0.04-5μm0.04-5μm 0.04-5μm0.04-5μm 0.04-5μm0.04-5μm 0.04-5μm0.04-5μm 2-10μm2-10μm 5-15μm5-15 μm Al 함량Al content 70wt%70wt% 65wt%65wt% 75wt%75wt% 70wt%70wt% 76wt%76wt% 72wt%72wt% 72wt%72wt% 휨(mm)Deflection (mm) 0.3-0.50.3-0.5 0.3-0.50.3-0.5 0.7-1.20.7-1.2 0.2-0.30.2-0.3 1.8-2.51.8-2.5 1.5-2.01.5-2.0 2.5-3.02.5-3.0 Bemp수Bemp number 00 1 - 21-2 00 5 - 85-8 00 10 - 1210-12 15 - 2015-20

실시예 1Example 1 실시예 2Example 2 실시예 3Example 3 비교예 1Comparative Example 1 비교예 2Comparative Example 2 비교예 3Comparative Example 3 비교예 4Comparative Example 4 Pmax (W)Pmax (W) 4.164.16 4.0774.077 4.0884.088 3.8993.899 4.0594.059 3.9003.900 3.8893.889 효율 (%)efficiency (%) 17.41917.419 17.0717.07 17.1117.11 16.3216.32 16.9816.98 16.3216.32 16.27516.275 FF(%)FF (%) 78.1578.15 78.278.2 77.5977.59 77.1377.13 77.2477.24 75.9175.91 77.9377.93 IscIsc 8.529258.52925 8.4158.415 8.4788.478 8.2798.279 8.4758.475 8.3418.341 8.1828.182 VocVoc 0.624430.62443 0.61970.6197 0.61250.6125 0.61070.6107 0.62000.6200 0.61590.6159 0.60950.6095 RsRs 0.007460.00746 0.006880.00688 0.007190.00719 0.007670.00767 0.007490.00749 0.007960.00796 0.006630.00663

※ Pmax = 태양전지 Cell의 최대 출력 Watt※ Pmax = maximum output watt of solar cell

Isc = 단락 전류(A)Isc = short circuit current (A)

Voc = 개방 전압(V)Voc = open voltage (V)

Rs = Series ResistanceRs = Series Resistance

FF = Fill Factor
FF = Fill Factor

Claims (5)

조성물 총 중량에 대하여 0.01μm ~ 5μm의 평균입도분포를 갖는 알루미늄 분말 65 ~ 75 중량%; 글라스 프릿 0.01 ~ 5 중량%; 및 유기 비히클 용액 20 ~ 34.90 중량%를 포함하는 태양전지 후면 전극용 알루미늄 페이스트.65 to 75% by weight of aluminum powder having an average particle size distribution of 0.01 μm to 5 μm relative to the total weight of the composition; 0.01-5% by weight of glass frit; And 20 to 34.90 wt% of an organic vehicle solution. 청구항 1에 있어서, 상기 글라스 프릿은 Bi2O3-SiO2-Al2O3-B2O3-SrO계 글라스 프릿인 것을 특징으로 하는 태양전지 후면 전극용 알루미늄 페이스트.The aluminum paste for solar cell back electrode of claim 1, wherein the glass frit is a Bi 2 O 3 -SiO 2 -Al 2 O 3 -B 2 O 3 -SrO-based glass frit. 청구항 2에 있어서, 상기 글라스 프릿은 Bi2O3 20-30mol%, Al2O3 5-15mol%, SiO2 25-35mol%, SrO가 1-10mol% 및 B2O3 20-40mol%를 포함하는 것을 특징으로 하는 태양전지 후면 전극용 알루미늄 페이스트.The glass frit according to claim 2, wherein the glass frit contains 20-30 mol% of Bi 2 O 3, 5-15 mol% of Al 2 O 3, 25-35 mol% of SiO 2, and 1-10 mol% of SrO and 20-40 mol% of B 2 O 3 . Aluminum paste for solar cell back electrode comprising a. 청구항 3에 있어서, 상기 글라스 프릿의 연화점이 400~600℃인 것을 특징으로 하는 태양전지 후면 전극용 알루미늄 페이스트.The aluminum paste for solar cell back electrode of claim 3, wherein the softening point of the glass frit is 400 to 600 ° C. 청구항 1의 알루미늄 페이스트를 사용하여 후면 전극을 형성하는 공정을 포함하는 것을 특징으로 하는 태양전지의 제조방법.A method of manufacturing a solar cell, comprising the step of forming a back electrode using the aluminum paste of claim 1.
KR1020100085604A 2009-09-04 2010-09-01 Aluminium paste for a back electrode of solar cell KR20110025614A (en)

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JP2012527829A JP2013504199A (en) 2009-09-04 2010-09-03 Aluminum paste for solar cell rear electrode
PCT/KR2010/005998 WO2011028058A2 (en) 2009-09-04 2010-09-03 Aluminum paste for a back electrode of solar cell
EP10813967.6A EP2474040A4 (en) 2009-09-04 2010-09-03 Aluminum paste for a back electrode of solar cell
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KR101276669B1 (en) * 2011-07-15 2013-06-19 주식회사 케이씨씨 Back contact composition for silicon solar cell comprising metal-containing organic additive
WO2014157958A1 (en) * 2013-03-27 2014-10-02 제일모직 주식회사 Composition for forming solar cell electrode and electrode produced from same

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EP2590177B1 (en) * 2011-11-04 2015-08-12 Heraeus Precious Metals North America Conshohocken LLC Organic vehicle for electroconductive paste
RU2531519C1 (en) * 2013-05-27 2014-10-20 Закрытое акционерное общество "Монокристалл" ЗАО "Монокристалл" Aluminium paste for silicon solar cells
JP2015115400A (en) * 2013-12-10 2015-06-22 東洋アルミニウム株式会社 Conductive aluminum paste

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KR100825880B1 (en) * 2004-07-01 2008-04-28 도요 알루미늄 가부시키가이샤 Paste composition and solar cell element employing same
JP4843291B2 (en) * 2005-10-18 2011-12-21 東洋アルミニウム株式会社 Aluminum paste composition and solar cell element using the same
ES2361974T3 (en) * 2005-10-20 2011-06-24 Toyo Aluminium Kabushiki Kaisha COMPOSITION OF PASTA AND SOLAR CELL ELEMENT THAT USES THE SAME.
US8076570B2 (en) * 2006-03-20 2011-12-13 Ferro Corporation Aluminum-boron solar cell contacts
KR101280489B1 (en) * 2007-05-09 2013-07-01 주식회사 동진쎄미켐 A paste for producing electrode of solar cell
TWI370552B (en) * 2007-06-08 2012-08-11 Gigastorage Corp Solar cell

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KR101276669B1 (en) * 2011-07-15 2013-06-19 주식회사 케이씨씨 Back contact composition for silicon solar cell comprising metal-containing organic additive
WO2014157958A1 (en) * 2013-03-27 2014-10-02 제일모직 주식회사 Composition for forming solar cell electrode and electrode produced from same
US9899545B2 (en) 2013-03-27 2018-02-20 Cheil Industries, Inc. Composition for forming solar cell electrode and electrode produced from same

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