Title :
Folded-Accumulation LDMOST: New Power MOS Transistor With Very Low Specific On-Resistance
Author :
Duan, Baoxing ; Yang, Yintang ; Zhang, Bo ; Hong, Xufeng
Author_Institution :
Key Lab. of the Minist. of Educ. for Wide Band-Gap Semicond. Mater. & Devices, Xidian Univ., Xi´´an, China
Abstract :
A new lateral power MOSFET structure [folded-accumulation LDMOS (FALDMOS)] is proposed, in which the silicon-substrate surface is trenched to form a folded shape from the channel to the drain electrode and the gate is extended to the drain. The majority-carrier accumulation layer is formed as the device is in on state due to the extended gate in the drift region whose concentration is higher than that in a conventional LDMOS at the same breakdown voltage (BV), resulting from the additional electric-field modulation, and an extra majority carrier is introduced on the sidewall of the trench, which reduced the on-resistance of the drift region further. In addition, the channel density is doubled because of trenching the folded channel, which reduced the channel on-resistance. It indicates by simulation that the specific on-resistance of 4.6 mOmegamiddotmm2 with a BV of 27.4 V in FALDMOS is lower than that of the previously reported lowest one.
Keywords :
electric breakdown; power MOSFET; FALDMOS; breakdown voltage; channel density; drift region; electric-field modulation; folded-accumulation LDMOST; lateral power MOSFET structure; majority-carrier accumulation layer; power MOS transistor; silicon-substrate surface; Lateral power MOSFET; majority-carrier accumulation; specific on-resistance;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2009.2032338
