TGV Wet Etching Technology

On the path of the semiconductor industry toward higher integration and smaller dimensions, an innovative technology originating in 2008—TGV (Through Glass Via)—is emerging. As a revolutionary alternative to TSV (Through Silicon Via) technology, TGV is rewriting the rules of high-end chip packaging by leveraging the unique advantages of glass materials. Among its manufacturing processes, the wet etching technique, as a core step in TGV fabrication, is a precision art worthy of in-depth exploration.

Translation of Semiconductor Etchant Technical Content

Silicon-based Materials: The mixed solution of HF and nitric acid (e.g., HNA system) achieves isotropic etching via synergistic oxidation-dissolution, suitable for silicon through-vias (TSV) and shallow trench isolation (STI).

Dielectric Layers: Buffered HF (BHF) solution (HF:NH₄F = 6:1) selectively etches SiO₂ (rate: 100 nm/min) by stabilizing fluoride ion concentration, with a selectivity ratio of 100:1 for Si₃N₄.
Key Parameters: HF concentration must be controlled at 5%–49%, and temperature fluctuation should be within ±1℃ to avoid side reactions (e.g., toxic NO₂ generation from HF and nitric acid).

Common problem points and corresponding treatment methods in the wet cleaning process of semiconductor wafers

Here is a systematic summary of common issues and corresponding handling methods in semiconductor wafer wet cleaning processes, integrating process principles and practical applications:

Wet Photoresist Stripping Process Flow - II. Full-Chain Analysis of Wet Stripping Process Flow

Wet stripping is not a single soaking step but a systematic process comprising pre-treatment, stripping reaction, multi-step rinsing, drying, and inspection. Each stage is interconnected and interdependent; deviations in parameters at any step may lead to issues like photoresist residue, surface corrosion, or structural damage.

Wet Photoresist Stripping Process Flow - Technical Positioning and Core Principles of Wet Stripping

Wet photoresist stripping is a process technology that uses chemical solutions to completely remove photoresist films and their residues from the wafer surface through physical dissolution, chemical degradation, or redox reactions. Compared with dry stripping (e.g., plasma stripping), wet stripping effectively avoids plasma-induced etching damage to sensitive layers on the wafer surface, making it particularly suitable for wafers containing delicate structures such as metal wiring and ultra-thin dielectric layers.