The Research And Fabrication Of Silicon-based Light Emitting Materials And Si-MSM-PD With Better Performance

Silicon based optoelectronic devices have been investigated greatly, because of the great advantages afforded by this approach: an available well-developed and widespread technology, monolithic integration with control/driving electronics and low cost. But silicon is an indirect bandgap semiconductor, which makes it extremely unlikely light emission by free carrier recombination. Silicon-based light emission is the most important problem in silicon-based optoelectronic integrated circuits (OEICs). On the other side, in order to fulfill silicon-based OEICs, silicon metal-semiconductor-metal photodetectors (Si-MSM-PDs) are very attractive for many optoelectronic applications, such as optical communication, high-speed chip-to-chip connection, and high-speed sampling, because of the planarity of the double Schottky contacts, without mesa structures or special epitaxial layers, so that they can be easily integrated onto a single chip with a bipolar or complementary metal-oxide-semiconductor(CMOS) transistor preamplifier. However, the low carrier mobility and low absorbance cause a poor photogenerated carrier collection efficiency and a small responsivity.In this paper, we have investigated silicon based luminescence materials and photodetector on two aspects as follows:Ⅰ. The fabrication and passivation of porous silicon(PS). We applied a novel method to fabricate and passivate PS by the aids of ozone(O3) to improve the PL efficiency. The performance test have showed very important advancement: 1. The PL of PS fabricated and passivated by the aids of O3 has been enhanced by nearly one order magnitude than that of PS fabricated by conventional method.2. The stabilization of PL has been enhanced greatly both under continuous laser for 30 minutes and placed in air for 158 days. The stabilization of our sample is much better than that has been reported nationally and abroad.3. We have explained the reason of performance improvement of our sample by analysing the chemical composition of PS with XPS and FTIR test.Ⅱ. The design and fabrication of silicon-based MSM photodetectors with improved performance.1. In order to improve the responsivity time and responsivity, we have designed a novel Si-MSM-PD with U-shape trench interdigitated electrodes. Besides, Si-MSM-PDs with different interdigitated space has also been designed.