Title :
Progress in Si-based AlGaN HEMTs for RF power amplifiers
Author_Institution :
Dept. of Electr. & Comput. Eng., Cornell Univ., Ithaca, NY, USA
Abstract :
The AlGaN high electron mobility transistor is currently the most suitable for high power amplification at microwave frequencies, due to its high breakdown field (3 MV/cm, which is 7.5 times that of GaAs) and its enormous polarization induced 2DEG at the AlGaN-GaN heterojunction. Its thermal conductivity of 1.3 W/cmK is good, but bulk GaN substrates are not available. The substrate of choice for nitride epitaxy is currently SiC, which has excellent thermal conductivity (3.3 W/cm K), but semi-insulating substrates are generally poor quality and limited to 2" diameters. Using a heteroepitaxial deposition process, it is possible to grow high quality AlGaN transistor structures directly on Si. The performance of these devices and the effects of substrate loading during RF operation are the subjects of this paper.
Keywords :
III-V semiconductors; MOCVD; aluminium compounds; gallium compounds; high electron mobility transistors; microwave field effect transistors; microwave power amplifiers; semiconductor device breakdown; semiconductor growth; thermal conductivity; two-dimensional electron gas; vapour phase epitaxial growth; wide band gap semiconductors; 2 in; AlGaN high electron mobility transistor; AlGaN transistor structures; AlGaN-GaN; AlGaN-GaN heterojunction; RF operation; RF power amplifiers; Si; Si-based AlGaN HEMTs; SiC; SiC substrate; breakdown field; bulk GaN substrates; device performance; heteroepitaxial deposition process; microwave frequencies; nitride epitaxy; polarization induced 2DEG; power amplification; quality; semi-insulating substrates; substrate loading effects; thermal conductivity; Aluminum gallium nitride; Electric breakdown; HEMTs; MODFETs; Microwave frequencies; Power amplifiers; Radio frequency; Radiofrequency amplifiers; Substrates; Thermal conductivity;
Conference_Titel :
Silicon Monolithic Integrated Circuits in RF Systems, 2001. Digest of Papers. 2001 Topical Meeting on
Conference_Location :
Ann Arbor, MI, USA
Print_ISBN :
0-7803-7129-1
DOI :
10.1109/SMIC.2001.942360
