Scanned-laser microscope for photolurminescence studies

Area of Science:

• Materials Science
• Optoelectronics
• Semiconductor Physics

Background:

• Photoluminescence (PL) is a key technique for characterizing semiconductor materials.
• Evaluating semiconductor wafer quality is crucial for optoelectronic device performance, particularly for light-emitting diodes (LEDs).
• Existing methods may lack the spatial resolution or speed required for comprehensive wafer evaluation.

Purpose of the Study:

• To develop and present a novel scanned-laser microscope for generating photoluminescence maps of semiconductor samples.
• To demonstrate the utility of this microscope for evaluating semiconductor wafers intended for LEDs.
• To detail the design, construction, and performance of a prototype instrument.

Main Methods:

• Development of a scanned-laser microscope system.
• Utilizing photoluminescence to generate spatial maps (images) of semiconductor wafers.
• Performance testing of the prototype, including spatial resolution and spectral definition measurements.

Main Results:

• The photoluminescence microscope achieves a spatial resolution near 10(-3) cm.
• It offers a spectral definition of 100 Å and can scan an area of 0.6 cm x 0.6 cm in seconds.
• Demonstrated application to testing GaAsP wafers, comparing results with other testing methods.

Conclusions:

• The developed scanned-laser microscope is a valuable tool for semiconductor wafer evaluation.
• It provides efficient and high-resolution photoluminescence mapping for quality assessment.
• The instrument shows significant promise for optimizing materials used in light-emitting diode fabrication.