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Technology

Dynamic Laser Stimulation (DLS)

The goal of DLS is to localize areas that are involved in a device which exhibits abnormal dynamic behavior or failure. Preparation for performing DLS requires that the test stimulus of the device be set on either side of the limit between its normal functionality (PASS) and its abnormal functionality (FAIL). DLS is performed by applying a dynamic stimulus to the device while simultaneously scanning a continuous laser beam on a device from the front or backside. The PASS/FAIL condition is monitored during this process. The laser stimulation effects on the device behavior are observed for each laser beam position through the PASS or FAIL results of a test pattern that highlights an abnormal device behavior or failure. Laser scanning is used to locally perturb the device electrical properties, resulting in a switch from FAIL-to-PASS or from PASS-to-FAIL. The device status PASS or FAIL is observed using the LSM DLS video channel input, and sensitive regions are visually marked.

Shmoo plot showing the PASS/FAIL status of a device for two parameters (X, Y) such as voltage, frequency and temperature

schmoo

DLS Thermal Laser Stimulation (TLS) Techniques

TLS uses the 1340nm laser beam to induce heating. Best suited for localizing soft defects in the interconnect layers such as resistive via.

Beaudoin, F; R Desplats & P Perdu et al. (2004), "Principles of Thermal Laser Stimulation Techniques", Microelectronics Failure Analysis (ASM International): 417-425, ISBN 0-87170-804-3.
Cole, E. I; P Tangyunyong & D.L Barton ( 1998), "Backside Localization of Open and Shorted IC Interconnections", 36th Annual International Reliability Physics Symposium (The Electron Device Society and the Reliability Society of the Institute of Electrical and Electronics Engineers, Inc.): pp. 129-136, ISBN 0-7803-4400-6.
Falk, R.A (2001), "Advanced LIVA/TIVA Techniques", Proceedings of the 27th International Symposium for Testing and Failure Analysis (ASM International): pp. 59-65, ISBN 0-87170-746-2.
Nikawa, K & S Tozaki (1993), "Principles Novel OBIC Observation Method for Detecting Defects in Al Stripes Under Current Stressing", Proceedings of the 19th International Symposium for Testing and Failure Analysis (ASM International): pp. 303-310, ISBN 0-87170-498-6.
Cole, Ed & et al (2004), written at Materials Park, "Beam-Based Defect Localization Methods", Microelectronics Failure Analysis (ASM International), ISBN 0-87170-804-3.
Antoniou, Nicholas (2004), written at Materials Park, "The Process of Editing Circuits Through the Bulk Silicon", Microelectronics Failure Analysis (ASM International), ISBN 0-87170-804-3.

Soft Defect Localization (SDL)

M.R. Bruce et al. “Soft Defect Localization (SDL) on ICs” ISTFA (2002) 21-27

Resistive Interconnect Localization (RIL)

E.I. Cole Jr. et al. “Resistive Interconnection Localization” ISTFA (2001) 43-50

DLS Photoelectric Laser Stimulation (PLS) Techniques

PLS uses the 1064nm laser beam to induce photo-current into the circuit. Best suited for localizing areas involved in timing race.

Laser Induced Device Alteration (LADA)

Kong, C. H.; Castro, E. P. (2006), "Application of LADA for Post-Silicon Test Content and Diagnostic Tool Validation", Proceedings of the 32nd International Symposium for Testing and Failure Analysis (ASM International): 431-7, ISBN 0-871170-844-2.
Rowlette, J; Eiles, T. (2003), "Critical Timing Analysis in Microprocessors Using Near-IR Laser Assisted Device Alteration (LADA)", International Test Conference 2003 Proceedings (International Test Conference): 264-73, ISBN 0-7803-8106-8.
J.A. Rowlette et al. “Critical Timing Analysis in Microprocessors Using Near-IR Laser Assisted Device Alteration (LADA)” ITC (2003) 264-273.

DLS References

F. Beaudoin et al. “Dynamic Laser Stimulation Techniques For Advanced Failure Analysis and Design Debug Applications” Microelectronics Reliability 47 (2007) 1527-1532.
F. Beaudoin et al. “Laser Stimulation Applied to Dynamic IC Diagnostics” ISTFA (2003) 371-377.