Fabrication and Study of InterdigitatedBack-side Metal Contact Silicon Nanowires Based Solar Cells

• Main Authors: Ming-Chun Tsai, 蔡茗竣
• Other Authors: Chien-Wei Liu
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/55997592079632605110

碩士 === 國立雲林科技大學 === 機械工程系碩士班 === 99 === The objective of this study is to fabricate and study the interdigitated back-side metal contact (IBC) silicon nanowires (SiNWs) based solar cells. In this thesis, the feasibility study was done which included with the (1) designs of structures, fabrication processes and photomask layouts of IBC SiNWs based solar cells, (2) texturing and saw damage removal of silicon wafer by using the different KOH solution, (3) PECVD Si3N4 antireflective coating (ARC), (4) phosphorous and boron ions thermal diffusion for the formations of p+ and n+ emitters, and (5) SiNWs formation by using electroless metal deposition (EMD). The testing results show that the micropyramids texture with a structure size range of 5-7μm were formed by using the 1.8 % KOH solution at 80oC for 18 min. The KOH concentrations in the range of 35-45% at 80oC were used to remove the contaminants and saw damages on the surface of silicon wafer completely after a chemical mechanical pulishing (CMP) process. The antireflective coating result shows that a bi-layer of SiOx (thermal dry oxide)/Si3N4 (PECVD) with a thickness of 800A obtained a lowest reflectance of near 0% in the wavelength range from 500nm to 700nm and an average reflectance of less than 5% in the wavelength range from 400nm to 1100nm. The sheet resistances (Rs) of p+ and n+ emitters were a range of 0.5-2.0 Kohm/square and a range of 10-30 ohm/square by using the phosphorous and boron ion thermal diffusion processes, respectively. The SiNWs array shapes of (100) Si and (110) Si was vertical and inclined after the AgNO3/HF mixed acids etching, respectively. The SiNWs array of (100) Si obtained an average reflectance of less than 5% without using ARC film in the wavelength range from 300nm to 1100nm.