Research On Deep-Submicrometer Fully Depleted SOI BJMOSFET

The fully depleted SOI device, which can overcome the shortage of Si device and exert the potential of silicon integration techonology, has reached very comprehensive application in high performance ULSI, VHSI, high voltage, high temperature, anti-eradiating, low voltage and low consumption, memorizer and three-dimensional integration field, and so on. Along with the fast development of SOI technology, all kinds of new-style SOI devices have been advanced, which can satisfy the request of different circuits. The deep-submicrometer fully depleted SOI BJMOSFET factured on SOI substrate by fully depleted SOI technology has more excellent performance compared to traditional MOSFET. Firstly, the analytical model of fully depleted SOI BJMOSFET threshold voltage has been established by solving the two dimensional Possion equation of its channel section and considering the influence of the two dimensional electric field domino offect. And then the threshold voltage expression has been found based on some almost condition. After the characteristic of threshold voltage of deep-submicrometer fully depleted SOI BJMOSFET and SOI MOSFET have been analyzed numerically, the advantage of the new-style SOI device in threshold voltage has been proved. Sencondly, the I-V characteristic of fully depleted SOI BJMOSFET has been analyzed theoretically and its I-V characteristic curves have been achieved. Compared to deep-submicrometer fully depleted SOI MOSFET at the same condition, it’s proved that the new-style SOI device has much higher output current. Thirdly, the capacitance model and high frequency equivalent model of deep-submicrometer fully depleted SOI BJMOSFET have been established based on the theoretical analysis of its frequency characteisitic and its AC characteristic has been simulated by the software of HSPICE. Compared to the fully depleted SOI MOSFET, we can see that the deep-submicrometer fully depleted SOI BJMOSFET has preferably frequency characteristic. Lastly, its temperature characteristic has been analyzed theoretically and simulated by computer, which proved that the deep-submicrometer fully depleted SOI BJMOSFET had all right temperature characteristic.