• 반도체디스플레이기술학회지
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• 제9권3호
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• pp.5-9
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• 2010

Recently, the important issues of solar cell are low cost and high efficiency. Making low cost and high efficiency solar cell, there are many effects to development of inexpensive wafer, simplify process and improve optical, electrical properties. In this the study, the 2 step texturing method using micro blaster was developed to decrease reflection of incident lights. Air bridge electrode structure is suggested to expand the effective surface area and decrease the series resistance of finger electrode. The effects of 1 step texturing and 2 step texturing by micro blaster are compared. Reflectance of 1 step and 2 step texturing are measured 28.7% and 25.5%, respectively. The reflectance of 2 step texturing sample is lower about 3.2% than 1 step textured sample.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.19-20
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• 2006

Two methods that can reduce reflectance in solar cells are surface texturing and anti-reflection coating. Wet chemical etching is a typical method that surface texturing of multi-crystalline silicon. Wet chemical etching methods are the acid texturization of saw damage on the surface of multi-crystalline silicon or double-step chemical etching after KOH saw damage removal too. These methods of surface texturing are realized by chemical etching in acid solutions HF-$HNO_3$-$H_2O$. In this solutions we can reduce reflectance spectra by simple process etching of multi-crystalline silicon surface. We have obtained reflectance of 27.19% m 400~1100nm from acidic chemical etching after KOH saw damage removal. This result is about 7% less than just saw damage removal substrate. The surface morphology observed by microscope and scanning electron microscopy (SEM).

• KSTLE International Journal
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• 제2권2호
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• pp.133-137
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• 2001

This paper investigates the correlation between strip surface roughness and the surface of the work roll. As the actual temper mill(TM) is used, this data will be adopted to another actual temper mill for the application and operation of this experiment. Conclusions are as follows: Electro-discharge texturing(EDT) roll has homogeneous roughness distribution and shape, and also a sinuous peak surface and the life is 2 times longer than that of shot blast texturing(SBT) method. And the higher surface roughness of work roll, the more time is necessary at the EDT method. In the SBT method without the correlation of roughness, but impeller rotation speed with an uncontrollable peak count. The roughness of SBT roll is irregularity compared to that of EDT roll because the work roll roughness is transferred to the strip which was temper rolled, and produces a more desirable image and greater clarity to the color painted steel sheet.

• 한국전기전자재료학회논문지
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• 제25권1호
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• pp.58-61
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• 2012

In our report a relatively simple process for fast nano-texturing of p-type(100) CZ- silicon surface using silver catalyzed wet chemical etching in aqueous hydrofluoric acid (HF) and hydrogen peroxide solution($H_2O_2$) at room temperature. The wafers were saw-damaged by NaOH(6 wt%) at $60^{\circ}C$ for 150s. To obtain a nano-structured black surface, a thin layer of silver with thickness of 1 - 10 nm was deposited on the surfaces by evaporation system. After this process the samples were etched in HF : $H_2O_2$ : $H_2O$ = 1:5:10 at room temperature for 80s - 220s. Due to the local catalytic of the Ag clusters, this treatment results in the nano-scale texturing on the surface. This resulted in average reflectance values less than 9% after the silver on the surface of the wafers were removed.

• 한국표면공학회지
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• 제40권3호
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• pp.138-143
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• 2007

The effects of texturing and anti-reflection coating on the reflection properties of multi-crystalline silicon solar cell have been investigated. The chemical solutions of alkaline and acidic etching solutions were used for texturing at the surface of multi-crystalline Si wafer. Experiments were performed with various temperature and time conditions in order to determine the optimized etching condition. Alkaline etching solution was found inadequate to the texturing of multi-crystalline Si due to its high reflectance of about 25%. The reflectance of Si wafer texturing with acidic etching solution showed a very low reflectance about 10%, which was attributed to the formation of homogeneous. Also, deposition of ITO anti-reflection coating reduced the reflectance of multi-crystalline si etched with acidic solution($HF+HNO_3$) to 2.6%.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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• pp.111-115
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• 2011

Surface Texturing is an essential process for high efficiency in multi-crystalline silicon solar cell. In order to reduce the reflectivity, there are two major methods; proper surface texturing and anti-reflection coating. For texturization, wet chemical etching is a typical method for multi-crystalline silicon. The chemical solution for wet etching consists of HF, $NHO_3$, DI and $CH_3COOH$. We carried out texturization by the change of etching time like 15sec, 30sec, 45sec, 60sec and measured the reflectivity of textured wafers. As making the silicon solar cells, we obtained the conversion efficiency and relationship between texturing condition and solar cell characteristics. The reflectivity from 300nm to 1200nm was the lowest with 15 sec texturing time and 60 sec texturing time showed almost same reflectivity as bare one. The 45 sec texturing time showed the highest conversion efficiency.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.945-950
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• 2004

Surface texturing of tribological application is another attractive technology of friction reducing. Also, reduction of friction is therefore considered to be a necessary requirement for improved efficiency of machine. In this paper attempts to investigate the effect of density for micro-scale dimple pattern on bearing steel flat mated with pin-on-disk. We demonstrated the lubrication mechanism for a Stribeck curve, which has a relationship between the friction coefficient and a dimensionless parameter for lubrication condition. It is found that friction coefficient is depended on the density of surface pattern. It was thus verified that micro-scale dimple could affect the friction reduction.Lubrication condition regime has an influence on the friction coefficient induced the density of micro dimple.

• Current Photovoltaic Research
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• 제6권3호
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• pp.86-90
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• 2018

To generate more current in crystalline silicon solar cells, surface texturing is adopted by reducing the surface reflection. Conventionally, random pyramid texturing by the wet chemical process is used for surface texturing in crystalline silicon solar cell. To achieve higher efficiency of solar cells, well ordered inverted pyramid texturing was introduced. Although its complicated process, superior properties such as lower reflectance and recombination velocity can be achieved by optimizing the process. In this study, we investigated optical and passivation properties of inverted pyramid texture. Lifetime, implied-Voc and reflectance were measured with different width and size of the texture. Also, effects of chemical rounding at the valley of the pyramid were observed.

• 한국정밀공학회지
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• 제12권5호
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• pp.69-76
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• 1995

This paper describes characteristics of EDT(Electro Discharge Texturing) and that the strip surface has influence on the paintability. The pulse mode and the capacitor mode of recently developed EDT method were investigated about the peak shape and the roughness of strip surface. And EDT method compared the above-mentioned contents with the SBT(Shot Blast Texturing) method. The peak count of the pulse mode is more than that of the capacitor mode. But the lower roughness below the Ra 3.2 .mu. m of the strip surface, the texturing time of the pulse mode is longer than the capacitor mode. In SBT method, the peak shape is similar to capacitor mode. But the EDT roll has more uniformity than the SBT roll and has more peak count than that of SBT roll. Therefore, in the painted steel sheet, EDT roll gives better surface of clarity image than the SBT roll.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.156-158
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• 2009

우리 연구팀은 $SiO_2$ nanospheres를 이용한 natural lithography를 통해 2가지 방법으로 GaAs 기판의 반사율을 감소시켰다. 먼저 GaAs 기판 위에 benzocyclobutene(BCB) 고분자를 코팅한 후, 그 위에 $SiO_2$ nanospheres를 코팅한다. 그리고 고분자의 유리전이 온도이상으로 가열하면 $SiO_2$ nanospheres가 고분자 속으로 가라앉게 되어 렌즈 형태의 표면이 형성된다. 또한, 이 상태에서 BOE 용액을 통해 $SiO_2$ nanospheres를 제거하여 오목한 형태의 표면을 형성할 수 있다. 이러한 2가지 방법의 surface texturing을 통해 우리는 GaAs 표면의 반사도를 각각 400~800nm의 파장에서 평균 13.6%~16.52%의 반사율을 얻을 수 있었다.