Solutions / Compound
Compound semiconductor inspection for GaN and SiC
Epitaxial layer defects, substrate bow detection, and compound-crystal defect classification — for power semiconductor manufacturers.
Compound Semiconductor
GaN and SiC defect detection
Compound semiconductors have fundamentally different crystal structures and defect modes compared to silicon. Lenspathio's compound semiconductor module uses dedicated optical calibration and training data developed on GaN and SiC substrate sets.
Epitaxial layer defects
Threading dislocations, inversion domains, and V-pit defects in GaN epitaxial layers. Visible in UV fluorescence mode — the system switches illumination wavelength automatically for compound semiconductor lots.
Substrate bow detection
GaN-on-silicon substrates develop significant bow during epitaxial growth. Bow magnitude and direction are mapped across the wafer surface using interferometric analysis — flagged when bow exceeds process limits.
Hexagonal crystal defects
Basal plane dislocations and stacking faults in 4H-SiC substrates. These defect types have hexagonal symmetry visible in optical darkfield mode — a different signature than silicon crystal defects.
Edge exclusion zone
Compound semiconductor wafers — especially GaN-on-silicon — show edge cracking and delamination modes in the exclusion zone. Dedicated edge scan mode maps the full perimeter at 5μm spatial resolution.
Surface contamination
GaN epitaxial surfaces are sensitive to metallic contamination from handling. The particle classifier is calibrated for compound semiconductor surface optical properties — different reflectance and roughness compared to silicon.
SiC micropipe detection
Hollow core screw dislocations (micropipes) in SiC substrates — a critical defect mode for high-voltage power device yield. Detected in brightfield mode with sub-10μm spatial resolution across the full 150mm substrate.
Evaluation
The 0.1% FPR holds on compound wafers
Compound semiconductor wafer surfaces are optically noisier than silicon. We invested specifically in training data from GaN and SiC substrate lots to meet the same FPR specification that logic and memory fabs require.
GaN-calibrated optical parameters
The inspection system adjusts illumination wavelength, numerical aperture, and background subtraction parameters automatically when a GaN substrate lot is loaded. No manual recipe switching required.
SiC 4H/6H polytypes
Both 4H-SiC and 6H-SiC substrate polytypes are supported. Polytype classification is performed automatically at lot load — the system selects the correct defect classification model without operator input.
GaN and SiC evaluation program.
Send us a GaN or SiC wafer set. We run the full inspection pipeline including UV fluorescence mode and produce a defect map with taxonomy breakdown for your specific substrate material and process step.