利用背面Ar^+轰击改善n沟MOSFET线性区的特性

Improvement of Characteristics in Linear Region of n-MOSFET Using Backsurface Ar^+ Bombardment

研究了利用背面Ar+轰击改善n沟金属 -氧化物 -半导体场效应晶体管 (n_MOSFET)线性区的特性 .用低能量 (5 5 0eV)的Ar+轰击n MOSFET芯片的背面 ,能有效地改善其线性区的直流特性 ,如跨导、沟道电导、阈值电压、表面有效迁移率以及低频噪声等 .实验结果表明 ,随着轰击时间的增加 ,跨导、沟道电导和表面有效迁移率先增大 ,然后减小 ;阈值电压先减小 ,随后变大 ;而低频噪声在轰击后明显减小 .实验证明 ,上述参数的变化是硅

Improvement of the characteristics in the linear region of n MOSFET using the backsurface Ar + bombardment has been investigated. A low energy (550 eV) argon ion beam is applied to bombard the backside of n MOSFET chip, thus the electrical characteristics of the transconductance, channel conductance, threshold voltage, effective inversion layer carrier mobility and low frequency noise of the devices in the linear region can be improved. The experiment results indicate that, as the bombardment time increases, the transconductance, channel conductance and effective inversion layer carrier mobility increase at first, and then decrease; the change tend of the threshold voltage is on the contrary; but the low frequency noise decreases evidently after bombardment. It is proved that the improvement of these parameters is due to the decrease of interface state density and fixed charge density.