Phenomenological nanoindentation technique in quality control of optoelectronics devices

Multiphase and porous ceramic materials are being used as passive semiconductors for building modern optoelectronics devices. Prescreening of the critical parts for subsurface defects before assembly can prevent device failures in the field. A new nanoindentation based non-destructive method has been proposed where shapes of loading–unloading curves can fingerprint subsurface cracking and material porosity induced inelastic behavior in defected multiphase, rough and porous ceramic parts. In addition to the differences in nanoindentation loading-unloading curve shapes, nanohardness values associated with the cracked contact surfaces were 40% lower. The non-destructive nanoindentation results agree well with the destructive Knoop’s microhardness results. A commercially available nanoindentation instrument integrated into the tribometer together with high-resolution optical microscope was utilized for automated and qualitative/quantitative surface materials properties characterization of optoelectronics parts. The proposed instrument and nondestructive testing method can be used for quality control of optoelectronics parts before assembly, significantly improving the yields.