Backside failure analysis of GaAs MMIC ASICs

¹ THALES Microelectronics, CNES-THALES Laboratory, BPI 1414, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France
² THALES Research and Technology, L'orée de Corbeville, BP 56, 91404 Orsay, France
³ CNES, BPI 1414, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France

Corresponding author: felix.beaudoin@cnes.fr

Received: 9 July 2003
Accepted: 10 February 2004
Published online: 15 July 2004

Abstract

A case study of backside failure analysis is performed on failed MMIC ASIC devices sealed in SOP packages. The use of Benzocyclobutene (BCB) as a dielectric material, which is etched during wet etch front-side decapsulation, motivated the proposed backside approach. Due to the transparency of the GaAs substrate to near infrared wavelengths, innovative optical defect localization techniques can be used. In this paper we present the successful application of Thermal Laser Stimulation (OBIRCH, TIVA) to rapidly, non-destructively and precisely localize the defects through the GaAs substrate. Backside delayering allowing defect observation and revelation is also discussed. Finally, an electrical interpretation of the failure and the corrective actions are presented.