金属与超薄非晶硅薄膜的接触特性研究

STUDY OF CONTACT CHARACTERISTICS OF METALS ON ULTRA-THIN HYDROGENATED AMORPHOUS SILICON LAYERS

研究金属与非晶硅薄膜(a-Si:H)的接触特性,用于晶体硅异质结太阳电池新型电极技术开发。采用等离子体增强的化学气相沉积(PECVD)技术制备超薄(~10 nm)a-Si:H薄膜,利用真空镀膜技术制作金属电极,采用圆点传输线模型(CDTLM)研究a-Si:H与不同金属(Al、Ni、Ti、In)的接触特性。低温退火后a-Si:H与Ni、Al、Ti可获得良好的欧姆接触。经200℃退火,p型非晶硅p-a-Si:H与Al的比接触电阻降至0.3 mΩ·cm^2;n型非晶硅n-a-Si:H与Ti的比接触电阻降至0.7 mΩ·cm^2,表明这两种金属可以直接用于a-Si:H薄膜的表面电极。

In this article, we studied the contact characteristics of metals on ultra-thin hydrogenated amorphous silicon （a-Si ： H）layers for the development of novel metal contacts and cell structures of silicon heterojunction solar ceils, a-Si： H thin layers were deposited with plasma enhanced chemical vapor deposition （PECVD） , and metal contacts were deposited with vacuum evaporation method. Contact characteristics between different metals （A1, Ni, Ti, In） and a-Si：H layers were studied by circular dot transmission line mode （CDTLM）. It demonstrated that good ohmic contact could be obtained between Ni, Al, Ti and a-Si ： H layers. Specific contact resistances as low as 0.3 mΩ· cm2 was obtained from A1 metal contact on p type a-Si： H layers, 0.7 mΩ·cm2 from Ti metal contact on n type a-Si： H layers, respectively, indicating the possible applications as novel contact method on a-Si ： H layers.