RF functional-based complete FA flow

Article history: Received 25 May 2015 Received in revised form 20 June 2015 Accepted 6 July 2015 Available online xxxx In this paper, we present a case study on Radio Frequency device,where a complete failure analysisflowhas been applied, built through integration of transversal competences from design, testing, and application teams. Key point is using functional failure as electrical fault activation. Indeed this approach allows enlarging the coverage of Failure Analysis to many functional failures reproducible through application board. The device under analysis is a frequency synthesizer, operating in the range of 2 GHz to 4 GHz, built in BiCMOS technology, failing on application at low temperature (−36 °C). Fault Isolation step is based on the replication of functional failure mode, through application board as electrical stimulus to activate the fault. Moreover, since failure is depending on temperature and voltage conditions, a Dynamic analysis through Laser Stimulus has been implemented (DLS) with a RTVM-like approach. This setup required specific adaption of application board in order to cope with mechanical and electrical constraints of DLS while reproducing failure mode in the GHz range. The amplitude variation of failing RF output signal wasmonitored by an additional circuitry that converted information of loss of signal in a suitable logic signal for DLS analysis. Fault Isolation pointed out to specific high frequency bipolar transistors on a divider block. Physical Analysis addressed to these components, which are key for this kind of products, put in evidence dislocations inside Si–Ge layer. © 2015 Elsevier Ltd. All rights reserved.