Previously, we updated the common issues in semiconductor wafer etching processes (1): Process Parameter Issues. Today, we present updates on (2) Equipment and Component-Related Issues and (3) Material Defects and Structural Anomalies.

(2) Equipment and Component-Related Issues

• Poor Plasma Stability: Uneven plasma or unstable discharge can lead to fluctuations in the etching rate, or even failure to generate effective plasma (e.g., when the pressure is too low).

• Impact of Key Components: Issues such as poor chamber sealing performance, corrosion of liners, and clogging of micro-pores in the gas distribution plate directly affect process repeatability.

• Equipment Contamination and Residue Accumulation: If reaction by-products (e.g., non-volatile residues) are not promptly removed, they may adhere to the wafer surface or chamber walls, causing etch stops or particle contamination.

(3) Material Defects and Structural Anomalies

• Crystal Defects and Mechanical Damage: Crystal slip line defects on the wafer surface (caused by uneven etching thermal stress) or mechanical scratches from polishing/sawing may exacerbate non-uniformity during etching.

• Challenges in Etching High Aspect Ratio Structures: In the etching of deep holes or trenches, insufficient ion energy or limited gas diffusion can reduce the etching rate at the bottom, leading to "micro-loading effects" or "skirt effects" (rough sidewalls).

• Sidewall Residues and Etching Deviations: Residues on pattern edges—formed by photoresist splashing or accumulation of reaction by-products—may cause short circuits or leakage currents.