应变SiGe SOI p-MOSFET温度特性研究

Research on Temperature Characteristics of SOI p-MOSFET with Strained SiGe Channel

SiGe SOI p-MOSFET在高频、高速、低功耗、抗辐射方面具有极大的优势。但二氧化硅埋层较低的热导率以及SiGe材料较低的热稳定性,使器件内部自加热效应的减弱或消除成为提高器件温度特性的关键因素。对应变SiGe SOI p-MOSFET温度特性机理进行研究,给出了三种缓解MOS-FET器件内部自加热效应的结构,并对其效果进行对比分析。结果表明:DSOI结构不适宜于低压全耗尽型SOI器件;Si3N4-DSOI结构对自加热的改善幅度较小;Si3N4埋层结构效果最好,尤其在低温领域改善更为明显。

The SOI p-MOSFET with strained SiGe channel has a great advantage in high-frequency, highspeed, low-power and anti-radiation. Because of lower thermal-stability of SiGe and lower heat-conductivity of SiO2, the temperature characteristics of SOI p-MOSFET with strained SiGe channel can be improved when internal self-heating effect of device is weakened or eliminated. The temperature characteristics mechanisms of the SOI p-MOSFET with strained SiGe channel are analyzed. Three kinds of structures are given to deduce self-heating effect of MOSFET and their improvements are also analyzed and compared. The results indicate that the DSOI structure is not suitable for the low voltage full depleted SOI device, and the improvement of Si3N4-DSOI on self-heating effect is not significant, and the Si3N4 buried layer structure is the best, especially in the field of low-temperature.