FREE-CARRIER ABSORPTION AND LUMINESCENCE DECAY OF POROUS SILICON

被引：8

作者：

GRIVICKAS, V

LINNROS, J

机构：

[1] Department of Electronics, Royal Institute of Technology, 164 40 Kista-Stockholm

来源：

THIN SOLID FILMS | 1995年 / 255卷 / 1-2期

关键词：

PHOTON EMISSION; QUANTUM EFFECTS; SILICON;

D O I：

10.1016/0040-6090(94)05606-E

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We present time-resolved photoluminescence (PL) and photo-induced free-carrier absorption measurements on free-standing porous silicon flakes at room temperature. The number of free carriers was monitored by absorption of infrared beams, at 3.39 mu m as well as at 1.3 mu m wavelength. The excellent scaling between these two wavelengths during the complete decay yields clear evidence for an absorption related to free carriers as in bulk Si. Furthermore, the total PL yield in the decay, integrated over the PL spectrum, scales with the photo-induced carrier concentration. Using the bulk-Si free-carrier absorption cross-section we find that of the order of 15% of the initially excited carriers remain after a fast initial transient, whereas only a few per cent recombine radiatively. The competition between various recombination channels is discussed.

引用

页码：70 / 73

页数：4