A microwave silicon power MOSFET

Abstract

A microwave power MOSFET t h a t c a n d e l i v e r 22W of output power a t 1.1GHz wi th 8.5dB g a i n w i l l be r epor t ed . U n t i l r e c e n t l y , b i p o l a r t r a n s i s t o r s h a v e b e e n t h e o n l y p r a c t i c a l s o l i d s ta te microwave power source, i n s p i t e of t h e i r f o r m a t i o n o f l o c a l i z e d h o t s p o t s t h a t limit t h e i r ASO's. On t h e o t h e r h a n d , t h e S i MOSFET seems t o h a v e p o t e n t i a l l y l a r g e power h a n d l i n g c a p a b i l i t i e s at microwave range, because of i t s high breakdown v o l t a g e and l a r g e AS0 c h a r a c t e r i s t i c s . The d e v i c e r e p o r t e d h e r e h a s 2 pm channel length and 80 nm t h i c k g a t e o x i d e f o r h i g h f r e q u e n c y performance, and a 70V breakdown v o l t a g e , a i d e d by a n o f f s e t c h a n n e l , f o r h i g h power. T h i s s t r u c t u r e was op t imized to g ive maximum ou tpu t power i n r e l a t i o n t o t h e i o n d o s e and breakdown vo l t age . In an expe r imen ta l ampl i f i e r test at 1.1 GHz, a maximum ou tpu t power of 22W ( t h e h i g h e s t power eve r r e p o r t e d f o r MOSFET s above LGHz) w i th 8.5dB g a i n and 51% d r a i n e f f i c i e n c y was measured. The device s t ruc ture , p rocess technology and per formance w i l l be desc r ibed .