ショットキダイオードのアドミタンス測定から評価したa-Si:Hの抵抗率の膜厚依存性

Abstract

The thickness dependence of resistivity for phosphorus-doped (PH_3/SiH_4≃0.1 at. %) a-Si : H was estimated from admittance measurements for Schottky diodes (Pt/n^- a-Si : H/n^+ a-Si : H/ITO/glass). The thickness of n^- a-Si : H layers were varied between 300 and 30000 Å. The activation energies of resistivity were independent of the thickness of n^- a-Si : H layers in the range 2900 to 30000 Å. On the other hand, it was found that the activation energies of resistivity decreased with thinner thickness between 300 and 2900 Å. It seemed that the decrease of the activation energies was due to the diffusion of phosphorus from n^+ a-Si : H layers during the deposition of n^- a-S : H layers.