METHOD AND APPARATUS TO FABRICATE VIAS IN THE GaN LAYER OF GaN MMICS

摘要

The method and apparatus to fabricate vias in the gallium nitride (“GaN”) layer of a GaN monolithic microwave integrated circuit (“MMIC”). The method and apparatus create vias in the GaN layer of a GaN MMIC through the use of controlled laser ablation and spectroscopic analysis of SiC and CVD diamond MMICs. The use of spectroscopic measurements helps to control the ablation by detecting a change in layers, including the GaN layer. The method and apparatus uses short pulse length, short wavelength, and a lower threshold intensity to remove material without undue heating or damage to the surrounding areas while retaining depth control.