Novel Failure Isolation Techniques for Circuits Sensitive to Microprobe

Voltage measurement of test pad directly by microprobe is typical technique in circuit isolation stage of failure analysis. But in some special circuits which are sensitive to microprobe, the voltage of some test pads will change when microprobe needle touches the test pads. Hence it is necessary to develop new measurement skills to confirm test pad status instead of measuring voltage directly. This paper introduces several novel measurement methods to solve this issue and demonstrates these skills with real cases.