Abstract

In this paper, GaN HEMT 1-chip high power amplifiers at S and C bands are presented, which are featured by the cell division configuration. Spurious oscillations, which often occur for large gate periphery microwave transistors, were suppressed by dividing 8 transistor cells in a single chip into 4 blocks each consisting of 2 cells and placing isolation resistors on matching circuits. 120W and 140W output powers were successfully extracted from single chip GaN HEMT transistors with 3.8W/mm and 2.8W/mm power densities at S and C bands, respectively. These are top-level output powers from single chip GaN HEMT transistors over 3GHz.