NEC Develops Nitride Semiconductor Power Transistor

NEC Corp. (Japan) announced that it has developed a nitride semiconductor power transistor capable of 2.3W power amplification in the sub-millimeter band (30GHz), almost thrice the output power of previous chip. The new transistor provides watt-grade power amplification without the need for the power divider/combiner that conventionally generated larger chip sizes and increased power loss. This results to a size 80 percent smaller than previous devices, but that can still cover the 22GHz, 26GHz and 38GHz HF bands.

The device employs 0.25µm ultra-fine gate electrodes using an electron beam lithography and hetero-junctions of GaN and AlGaN to realize a power-gain cutoff frequency of 120GHz, and a drain current density of up to 1A per 1mm-wide gate. It also adopts a silicon carbide substrate to allow parallel transistor elements to be operated at the same channel temperature.