Electroabsorption measurements and builthyphen;in potentials in amorphous siliconpndash;indash;nsolar cells

摘要

We present a technique for using modulated electroabsorption measurements to determine the builthyphen;in potential in semiconductor heterojunction devices. The technique exploits a simple relationship between the secondhyphen;harmonic electroabsorption signal and the capacitance of such devices. We apply this technique to hydrogenated amorphous silicon (ahyphen;Si:H)hyphen;based solar cells incorporating microcrystalline Sip+layers. For one set of cells with a conventional plasmahyphen;deposited intrinsic (i) layer we obtain a builthyphen;in potential of 0.98plusmn;0.04 V; for cells with anilayer deposited using strong hydrogen dilution we obtain 1.25plusmn;0.04 V. We speculate that interface dipoles between thep+andilayers significantly influence the builthyphen;in potential. copy;1996 American Institute of Physics.