Wafer inspection microscopeThe image of the wafer surface is magnified through an optical lens system and projected onto an eyepiece or imaging sensor for observation and analysis. Some microscopes also utilize different illumination methods and contrast techniques, such as bright field, dark field, differential interference contrast (DIC), etc., to enhance the contrast of the image, making defects and structural features clearer and more visible.
Wafer inspection microscopeThe applications are as follows:
1. Surface defect detection of wafers
Redundancy detection: By magnifying 50-1000 times and combining with optical MIX illumination, it accurately locates nanometer sized particles to micrometer sized dust, avoiding electrical characteristic failure.
Mechanical damage analysis: detect arc-shaped scratches caused by chemical mechanical polishing (CMP) and evaluate the impact of damage on circuit connectivity.
Crystal defect identification: Using DIC technology to identify slip lines and stacking faults, improving yield.
2. Quality control of photolithography process
Pattern alignment accuracy detection: Verify whether the circuit pattern formed by photoresist exposure and development meets the design requirements and avoids line width deviation.
Line width uniformity analysis: Measure line width changes using CD-SEM (electron beam imaging) or OCD (optical key dimension) equipment to ensure process stability.
3. Packaging testing and failure analysis
Solder joint quality inspection: Check the shape, size, and defects such as virtual soldering and short circuits of solder joints to ensure packaging reliability.
Interlayer alignment and thickness measurement: Verify the stacking accuracy of multi-layer metal/dielectric layers, measure interlayer thickness changes, and comply with design specifications.
Transmission electron microscopy (TEM) analysis: provides atomic level resolved cross-sectional images, combined with energy spectrum analysis of element distribution, to locate the root cause of failure.
4. Process support
Compound semiconductor detection: such as defect imaging on silicon carbide (SiC) substrates, supporting photoluminescence detection channels, clearly presenting lattice defects.
3D structure observation: By tilting and rotating the sample at multiple angles, the alignment accuracy and interface quality of the 3D stacked structure are detected.