Super-resolution laser probing of integrated circuits using algorithmic methods

Area of Science:

• Semiconductor device physics and testing
• Integrated circuit (IC) defect analysis
• Photonics and laser-based metrology

Background:

• Laser probing is crucial for diagnosing defects in integrated circuits (ICs) during electrical stress tests.
• Miniaturization of transistors below 20nm technology nodes causes signal crosstalk and degrades fault isolation due to limited laser focal spot accuracy.
• Existing methods struggle with precise defect localization in densely packed advanced ICs.

Purpose of the Study:

• To develop an advanced laser probing technique for accurate defect isolation in sub-10nm semiconductor technology nodes.
• To overcome the limitations of optical resolution and signal crosstalk in miniaturized ICs.
• To enable continued electrical probing of ICs without hardware modifications using sub-bandgap photon energies.

Main Methods:

• Implementation of patented algorithms including cross-correlations and clustering.
• Integration of previously developed combinational logic analysis for signal processing.
• Application of enhanced laser beam positioning with accuracy better than 10nm.

Main Results:

• Achieved beam positioning accuracy to better than 10nm.
• Extracted electrooptic waveforms from individual transistor nodes, surpassing the optical resolution limit by approximately 18 times.
• Successfully isolated and identified a specific fault on a defective integrated circuit device.

Conclusions:

• The developed algorithmic approach significantly enhances fault isolation capabilities in advanced ICs.
• This method enables continued probing of semiconductor technology nodes below 10nm without requiring hardware modifications.
• The technique allows for precise defect diagnosis even with signal crosstalk and reduced optical resolution.