• 한국재료학회지
• /
• 제23권2호
• /
• pp.116-122
• /
• 2013

For fabricating silicon solar cells with high conversion efficiency, texturing is one of the most effective techniques to increase short circuit current by enhancing light trapping. In this study, four different types of textures, large V-groove, large U-groove, small V-groove, and small U-groove, were prepared by a wet etching process. Silicon substrates with V-grooves were fabricated by an anisotropic etching process using a KOH solution mixed with isopropyl alcohol (IPA), and the size of the V-grooves was controlled by varying the concentration of IPA. The isotropic etching process following anisotropic etching resulted in U-grooves and the isotropic etching time was determined to obtain U-grooves with an opening angle of approximately $60^{\circ}$. The results indicated that U-grooves had a larger diffuse reflectance than V-grooves and the reflectances of small grooves was slightly higher than those of large grooves depending on the size of the grooves. Then amorphous Si:H thin film solar cells were fabricated on textured substrates to investigate the light trapping effect of textures with different shapes and sizes. Among the textures fabricated in this work, the solar cells on the substrate with small U-grooves had the largest short circuit current, 19.20 mA/$cm^2$. External quantum efficiency data also demonstrated that the small, U-shape textures are more effective for light trapping than large, V-shape textures.

• 한국자기학회지
• /
• 제11권4호
• /
• pp.163-167
• /
• 2001

DC 마그네트론 스퍼터링법으로 증착된 700 $\AA$의 NiFe 박막을 박막 증착시 형성시킨 자화용이축에 수직한 자기장을 인가하여 열처리한 후 일축 이방성 자기장의 회전을 조사하였다. NiFe 박막은 열처리온도 160 $^{\circ}C$에서 자화용이축과 자화곤란축을 구분할 수 없는 등방적인 상태가 되었고, 열처리온도가 증가함에 따라 다시 일축 이방성을 갖는 상태가 되었다. 열처리 온도가 400 $^{\circ}C$ 이상인 경우에 급격한 보자력의 증가를 보였다. 열처리 온도가 400 $^{\circ}C$인 경우에 XRD 분석과 AES depth profile은 NiFe 박막 내에서 (111) 방향으로 결정성장이 활발히 일어나며 인접한 전극 Au와 상호화산 현상도 광범위하게 일어남을 보여주었다.