Modular Wafer Inspection
with pco.edge 5.5

Abstract
In the last decade, the interest in silicon carbide (SiC) devices has significantly grown. SiC is a wide bandgap semiconductor, which is especially used for high-power, high-temperature and high-frequency devices due to its high energy efficiency. Despite great improvements in the material quality of SiC substrates and epitaxial wafers within the last years, critical defects like stacking faults (SFs) and basal plane dislocations (BPDs) can still lead to bipolar degradation and finally to complete failure of the device.

Different characterization methods have been developed to identify these defects on the wafer level, e.g., defect selective etching and x-ray topography. However, both methods are not suitable for fast inline quality control during device production, as they are either working in a destructive manner, or are cost intensive and time consuming.

For that reason INTEGO has developed a new multichannel SiC inspection system which allows fast, non-destructive and contactless detection of critical defects of SiC wafers along the device production chain at room temperature. 

INTEGO’s systems are designed for clean room environment ISO 4, and are capable of handling 100 mm, 150 mm and 200 mm SiC substrates, epitaxial wafers, or partially processed wafers. The modular system concept enables an individual configuration regarding inspection method, illumination type, and resolution capabilities. The high-speed sCMOS camera pco.edge 5.5 by PCO featuring high resolution, high frame rate, low noise, high dynamic range, and quantum efficiency guarantees highest image quality for optimized image evaluation.

INTEGO’s leading-edge systems can be equipped with up to three individual inspection stations for either high-throughput applications or flexible R&D usage. Each station has a high-precision microscopic stage and an individually designed photoluminescence, differential interference contrast (DIC), or bright/dark field microscopy unit. Depending on the chosen microscope magnification, an image resolution of up to 0.3 µm/pixel is possible, enabling detection, identification, and classification of a multitude of different defects even smaller than 1 µm.

INTEGO’s highly customisable systems therefore enable an efficient optimization and monitoring of the production process of different wafer types, saving time and reducing costs in material and device production.

Website: Intego GmbH