High Clarity Optical Borosilicate Glass Substrates In Semiconductor

High Clarity Optical Borosilicate Glass Substrates In Semiconductor

Material:

• Base Composition: Primarily silicon dioxide (SiO₂) and boron trioxide (B₂O₃) , with minimal alkali content.

• Manufacturing: Produced via continuous melting in platinum-lined furnaces to ensure extreme purity and homogeneity. Often polished to sub-nanometer surface roughness.

• Key Additives: Precise additions of alumina (Al₂O₃) for chemical stability and refining agents to eliminate bubbles/impurities.

Key Properties:

1. Exceptional Optical Clarity: Ultra-high light transmission (>90%) across UV to NIR spectra (e.g., 185nm-2μm), minimal autofluorescence.

2. Low Thermal Expansion (CTE): Extremely low CTE (∼3.3 × 10⁻⁶/K at 20°C), matching silicon wafers to prevent stress-induced failure during thermal cycling.

3. Superior Thermal & Chemical Resistance: Withstands aggressive semiconductor processes:

   • Thermal: Stable up to 500°C; resists thermal shock from rapid heating/cooling.

   • Chemical: Inert to acids, alkalis, and solvents (e.g., photoresist developers, etchants).

4. High Surface Quality: Near-atomic smoothness (<0.5nm Ra) critical for nanolithography and thin-film deposition.

5. Low Ionic Contamination: Minimal alkali ion migration (Na⁺, K⁺) prevents device contamination.

6. Mechanical Stability: High Young’s modulus (∼64 GPa) ensures dimensional rigidity under processing stress.

Primary Function:

• To serve as an ultra-stable, inert platform for semiconductor fabrication processes.

• Provides a defect-free surface for high-resolution patterning (e.g., EUV photomasks).

• Acts as a protective window for sensors and optics in harsh environments.

• Enables precise light transmission for inspection, metrology, and lithography systems.

Main Applications in Semiconductor:

1. Photomask Blanks: Base material for EUV/ArF photolithography masks requiring near-zero defects.

2. MEMS & Sensor Covers: Hermetic sealing caps for pressure sensors, IR detectors, and MEMS devices.

3. Wafer Handling Components: Carrier plates, inspection windows, and alignment stages in wafer processing tools.

4. Advanced Packaging: Interposers and substrates for 2.5D/3D IC integration.

5. Process Equipment Optics: Lenses, viewports, and mirrors in plasma etchers, CVD chambers, and laser tools.

6. Metrology & Inspection: Critical for high-precision alignment systems and defect scanners.

In essence: High Clarity Optical Borosilicate Glass Substrates are ultra-pure, thermally stable engineered materials essential for semiconductor manufacturing. Their unique combination of near-perfect optical transmission, near-zero thermal expansion, chemical inertness, and atomic-level surface flatness enables nanometer-scale precision in photolithography, protects sensitive components, and ensures reliability in extreme process environments. These substrates directly support yield and performance in advanced nodes (e.g., sub-5nm), MEMS production, and next-generation packaging.