Gallium nitride powerbar transistors with via holes fabricated by laser ablation

Published in:
phys. stat. sol. (c) 3, No. 3, 482-485 (2006).
© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the WILEY-VCH Verlag GmbH & Co. KGaA.

Abstract:
Low ohmic through-hole vias are fabricated for AlGaN/GaN HEMT powerbar devices on SiC substrates using laser ablation technique. A complete processing technique has been developed. Through-wafer micro holes with an aspect ratio of 4 were drilled using pulsed UV laser machining. A plating technique on steep side wall could be established. Feasibility and performance of laser drilled via holes were tested with large power devices and proved successful up to the packaging level. The device demonstrated 14 dB of linear gain and a saturated output power of 40 W.

Full version in pdf-format.