中国物理B ›› 2002, Vol. 11 ›› Issue (9): 944-947.doi: 10.1088/1009-1963/11/9/317
戴敏, 张林, 鲍云, 石建军, 张铠, 李伟, 黄信凡, 陈坤基
Dai Min (戴敏), Zhang Lin (张林), Bao Yun (鲍云), Shi Jian-Jun (石建军), Chen Kai (张铠), Li Wei (李伟), Huang Xin-Fan (黄信凡), Chen Kun-Ji (陈坤基)
摘要: Sandwiched structures (a-SiNx/a-Si/a-SiNx) have been fabricated by the plasma enhanced chemical vapour deposition technique. A Si nanocrystal (nc-Si) layer was formed by crystallization of an a-Si layer according to the constrained crystallization principle after quasi-static thermal annealing at 1100℃ for 30 min. Transmission electron microscopy (TEM) and Raman scattering spectroscopy clearly demonstrated that nc-Si grains were formed in the as-deposited a-Si layer after annealing. The density of nc-Si grains is about 1011cm-2 as shown by TEM photographs. Using capacitance-voltage (C-V) measurements we investigated the electrical characteristics of the sandwiched structures. The charge storage phenomenon of the nc-Si layer was observed from the shift of flat-band voltage (VFB) in C-V curves at a high frequency (1 MHz). We estimated the density of nc-Si grains to be about 1011cm-2 from the shift value of VFB, which is in agreement with the result of TEM photographs. At the same time, we found that the shift of VFB increased with the increase of the applied constant dc voltage or the thickness of the nc-Si layer.
中图分类号: (Quantum well devices (quantum dots, quantum wires, etc.))