Multi-step doped-channel camel-gate FETs with a linear and enhanced transconductance

Abstract

We report on the linear and enhanced transconductance by multi-step doped channel camel-gate field-effect transistors (CAMFETs) as compared with conventional CAMFETs. A low-doped layer along with the n + and p + layers is used to form a high-performance camel diode, which exhibits a large potential barrier so as not to drop rapidly. The measured barrier height is greater than 1.0 V. The measured gate-to-drain breakdown voltage at 1 mA/mm of gate current is about −21 V, whereas the rest layers doped heavily are used to enhance the transconductance and to improve the device linearity. A 1.5 x 100 μm 2 device has a peak transconductance of 220 mS/mm and a current density larger than 800 mA/mm. Furthermore, the device has a transconductance more than the peak value 80% over a wide drain current range from 160 to 800 mA/mm. The improvement of device linearity and the enhancement of current density suggest that the multi-step doped-channel F FETs are very promising far high power large signal circuit applications.