What is KOH Etching?
KOH Etching (Potassium Hydroxide etching) is a wet chemical etching process used to selectively etch silicon. It is anisotropic, meaning it etches silicon at different rates depending on the crystallographic orientation, enabling the creation of precise patterns and structures.
Applications in Semiconductor Device Fabrication
- Microfabrication for MEMS: Creates precise trenches, cavities, and 3D shapes for accelerometers, gyroscopes, and sensors.
- Wafer Thinning: Reduces wafer thickness for flexible electronics and stacked ICs.
- Cavity Formation: Produces smooth cavities for optical devices like mirrors and lenses.
- Etch-Stop Techniques: Enables precise layer removal for advanced device structures.
- Through-Silicon Vias (TSVs): Forms high-aspect-ratio trenches for 3D IC interconnects.
- Solar Cell Fabrication: Textures silicon wafers to increase light absorption and efficiency.
Advantages of KOH Etching
- Cost-Effective: Affordable compared to other etching methods.
- High Precision: Produces consistent, well-defined structures.
- Selective Etching: Compatible with silicon dioxide and silicon nitride masks.
- Scalable: Suitable for batch processing of wafers.