Polarization Difference Probing

Polarization Difference Probing (PDP) utilizes the interaction of infra-red light with active regions of a device under stimulation. A static phase shift is introduced between two orthogonally polarized laser beams, which are directed at the region-of-interest. A fluctuating signal on the node-of-interest introduces a modulated phase-shift in the light returned, which may be displayed as a timing waveform. Waveforms are easily obtained and are reproducible.

PDP References

• Lo, W. et al. (2004), "Polarization difference probing : a new phase detection scheme for laser voltage probing", ISTFA 2004: proceedings of the 30th International Symposium for Testing and Failure Analysis, ISBN 0871708078

Static Laser Stimulation

The aim of Static Laser Stimulation (SLS) is to localize current related defects such as shorts. It consists of scanning a continuous laser beam on the front or backside of the device under test (DUT). The laser stimulation effects on the device behavior are observed through a device power consumption change. Static Laser Stimulation is advantageously applied to detect defects in devices presenting an abnormal supply current (IDD) or supply current in the quiescent state (IDDQ).

Two types of laser stimulation can be employed:

Thermal Laser Stimulation (TLS) which uses the 1340nm laser beam to induce heating; known as Optical Beam Induced Resistance Change (OBIRCH) Thermally Induced Voltage Alteration (TIVA) or Seebeck Effect Imaging (SEI).

Thermal heating will affect the DUT current consumption through

• a resistance variation
• a thermoelectric energy conversion or Seebeck effect

TLS is best suited for localizing current related defects in the interconnect layers such as metallic or polysilicon shorts.

Photoelectric Laser Stimulation (PLS) which uses the 1064nm laser beam to induce photo-current into the circuit; known as Optical Beam Induced Current (OBIC) or Light Induced Voltage Alteration (LIVA).

Photo-currents are generated at silicon junction upon the dissociation of the photo generated free carriers. The photo-currents will directly impact the DUT current consumption.

PLS is best suited for localizing defects within p-n junctions such as melted silicon filaments. It can also be used to localize non-current related defects such as opens by comparing PLS images from a failed device with PLS images from a reference device.

TLS References

• 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.

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.

Two types of laser stimulation can be used:

Thermal Laser Stimulation which uses the 1340nm laser beam to induce heating; Known as Soft Defect Localization (SDL) or Resistive Interconnect Localization (RIL). Best suited for localizing soft defects in the interconnect layers such as resistive via.

Photoelectric Laser Stimulation which uses the 1064nm laser beam to induce photo-current into the circuit; Known as Laser Induced Device Alteration (LADA); Best suited for localizing areas involved in timing race.

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

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.
• J.A. Rowlette et al. “Critical Timing Analysis in Microprocessors Using Near-IR Laser Assisted Device Alteration (LADA)” ITC (2003) 264-273.
• M.R. Bruce et al. “Soft Defect Localization (SDL) on ICs” ISTFA (2002) 21-27
• E.I. Cole Jr. et al. “Resistive Interconnection Localization” ISTFA (2001) 43-50

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.

Focused Ion-beam Technology References

• Malik, T.; Jain, R.; Nicholson, R.; Lundquist, T. (2005) "Role of Circuit Edit in Post-Silicon Debug and Diagnostics," Silicon Debug and Diagnosis Conference.
• Sengupta,M.; Thompson, M. A.; Johri, L.; Lundquist, T. R. (2002) "Through-Silicon IR image to CAD database alignment" Proceedings of the 9th International Symposium on the Physical and Failure Analysis of Integrated Circuits, IPFA 2002, ISBN 0-7803-7416-9.
• Jain, R.; Lundquist, T.; Antolik, M.; Thompson, M. "Novel and practical method of through silicon FIB editing of SOI devices" ISTFA 2005: proceedings of the 31st International Symposium for Testing and Failure Analysis, ISBN 087170823X.
• Pajak, R.; Baiocchi, F.; Le Roy, E. "Dopant region imaging on front surface of silicon devices using a coaxial photon-ion column" ISTFA 2005: proceedings of the 31st International Symposium for Testing and Failure Analysis, ISBN 087170823X.
• Kerst, U. et al. "Contacting diffusion with FIB for backside circuit edit - procedures and material analysis" ISTFA 2005: proceedings of the 31st International Symposium for Testing and Failure Analysis, ISBN 087170823X.
• Ng, K., Motegi, S.; Jain, R.K.; Lundquist, T.R.; Makarov, V.V. "FIB Etching of Cu with Minimal Impact on Neighboring Circuitry, including Dielectric" Proceedings of the 12th International Symposium on the Physical and Failure Analysis of Integrated Circuits, 2005. IPFA 2005

Spray Cooling

• Goruganthu, R. R., et al. (2004) "Spray cooling for time resolved emission measurement of ICs " ISTFA 2004: proceedings of the 30th International Symposium for Testing and Failure Analysis, ISBN 0871708078

Device Navigation References

• Nicholson, Roger (2006), "Logical-to-physical Device Navigation using Place-and-Route Data as an Alternative to LVS," Proceedings of the 32nd International Symposium for Testing and Failure Analysis (ASM International):46-54, , ISBN 0-871170-844-2.
• Nicholson, R. & Suri, H. (2006), "Physical-to-Logical Mapping of Emission Data using Place-and-Route," ScienceDirect (Elsevier).
• Nicholson, R; Kardach, C; Cory, B. (2006), "The Role of ATPG Fault Diagnostics in Driving Physical Analysis," International Test Conference.
• Nicholson, Roger (May 2006), "Bringing Closer the Logical and Physical Worlds for Device Analysis: A Case Study," EDFA Magazine, May 2006.