The Physical Effects Simulation Of Soi Devices And Their Total Dose Radiation-hardened Technology

SOI ( Silicon-On-Insulator ) is one of the cutting-edge research focuses in microelectronics industry. Based on the demands and supports of special Funds for Major state Basic Research Projects and the National Natural Science Foundation of China, a series of investigations on the Self-heating effect of SOI device and the improvement of irradiation hardness techniques for SOI device and circuits have been made. Main results acquired are drawn as follows:The elementary model of temperature distribution has been erected and the mechanisms of giving birth to the Self-Heating effect for SOI device have been investigated. A classical 2-D device simulator named MEDICI has been used to discuss the influence caused by all kinds of the parameters of SOI device, such as the doping concentration of source/drain region, the doping concentration of the channel region, the thickness of the top silicon layer, the thickness of the buried oxide layer and so on. Lots of results have been gained. According to the results, all of the parameters of devices can give impacts on the Self-Heating effect for SOI device. With the increasing of the thickness of top silicon layer or the thickness of buried oxide layer, the influence of SOI device induced by the Self-Heating effect becomes more, on the contrary, with the decreasing of the thickness of top silicon layer or the thickness of buried oxide layer, the influence of SOI device induced by the Self-Heating effect becomes less. With the decreasing of the doping concentration of source/drain region, the Self-Heating effect becomes more, otherwise, becomes less. With the increasing of doping concentration of channel, the Self-Heating effect becomes more, otherwise, becomes less. Based on these results, a conclusion that the Self-Heating effect can be suppressed by optimizing the device parameters properly can be made.tAbstractTo suppress the Self-Heating effect of SOI device effectively, many papers from abroad have been surveyed and some new kinds of SOI structures have been proposed, such as SOIM, Silicon-On-ALN and sandwiched-layer SOI, which all have the ability to reduce the Self-Heating effect effectively. Specially, we have taken the lead in bringing forward the sandwiched-layer/SOI, which is a multi-layered structure formed by SiO2/SJ3N4/SiO2. The electrical characteristics of all these new kinds of structures have been simulated and many results have been got, which can prove that these kinds of SOI structures can recede the Self-Heating effect of SOI device availably.The unique structure of SOI device makes it have wonderful ability to resist the radiation effect, such as SEU ( Single Event Upset ) and the Dose-rate effect. However, the SOI device has many Si/SiO2 interfaces, which are quite sensitive to Total Dose irradiation effect. So the SOI device and circuits have been studied to improve their irradiation hardness capabilities. We have taken the lead in investigating the mechanism of Total Dose effect for NMOSFET/SOI by simulation. From the simulation results have been got, a conclusion that the irradiation hardness techniques of SOI device could be improved by regulating the device parameters properly.To improve the irradiation hardness performance of SOI device and circuits, we cooperated with Semiconductor Institute of Beijing, CAS. We have proposed the implantation of F+ into the top silicon layer or buried oxide layer of SIMOX wafer. Then the wafers implanted by F+ in different implanting conditions and the control SIMOX wafer have been taken to prepare the MOS/SOI. After finishing the 1C processing, the electrical characteristic of these SOI devices has been tested before and after the irradiation. During the testing, the irradiation bias equipment has been designed and made. From the testing results, it can tell us that the implantation of F+ by proper implantation energy and dose can enhance the irradiation hardness techniques for SOI devices, which is the most novel technology in China, and also is innovative in the world.Integrated with the other coll...