Spin-On Glass (SOG)
CAS Number: 7631-86-9
Spin-on glass (SOG) is a silica-based solution deposited by spin coating on semiconductor wafers and cured to form a planarizing silicon oxide film for gap-fill and interlayer dielectric (ILD) applications. It provides excellent gap-fill capability for sub-micron features without the need for high-vacuum deposition equipment. Available in silicate, siloxane, and hydrogen silsesquioxane (HSQ) chemistries.
Technical Specifications
| viscosity | 3–50 cP |
| appearance | Clear, colorless solution |
| cureCondition | 350–425°C / 30–60 min in N₂ |
| solidsContent | 5–25 wt% |
| refractiveIndex | 1.40–1.46 (cured film) |
| dielectricConstant | 3.0–4.0 (cured) |
Applications
- Sub-micron gap-fill dielectric
- Interlayer dielectric planarization
- Shallow trench isolation gap-fill
- Anti-reflective coating (ARC) underlayer
- Passivation layer in thin-film transistors
Key Features
- Excellent sub-micron gap-fill without void formation
- Spin-coat process eliminates need for CVD equipment
- Tunable refractive index and dielectric constant
- Compatible with standard CMOS cleaning and etching