Process Design Rules (PDR)
To ensure high yield and compatibility with our shared tooling environment, all incoming designs must adhere to the following contamination control and geometry specifications.
Material & Contamination Classes
Class 1
CMOS-Clean
Strictly limited to CMOS-compatible materials to protect high-temp furnaces.
- Allowed: Prime Si, Thermal SiO2, LPCVD Nitride/Poly.
- Prohibited: All Metals, Glasses (Pyrex/Borofloat), Mobile Ions (Na, K).
Class 3
Metals & General
Broader compatibility for MEMS, microfluidics, and back-end processing.
- Allowed: Gold (Au), Copper (Cu), Nickel (Ni), III-V compounds, Glass/Quartz.
- Constraint: Once a wafer enters a Class 3 tool, it cannot return to Class 1 furnaces without strict decontamination protocols.
Substrate Standards
Wafer Sizes & Geometries
- Optimized Standard: 100mm (4") Silicon. (Baseline for highest resolution Litho & DRIE).
- Supported: 150mm (6") Silicon (Available for blanket films and specific steppers).
- Piece Processing: Chips/Pieces must be mounted to a 100mm Carrier Wafer using Crystalbond or thermal paste for automated handling.
Transparent Substrates (Glass/Quartz)
Transparent wafers require special handling for automated optical sensors (e.g., wafer robot end-effectors). Please explicitly specify if using Fused Silica, Borofloat, or Quartz to ensure correct cassette mapping.
Lithography Specifications
| Tool Type | Min Resolution | Alignment Accuracy | Notes |
|---|---|---|---|
| Projection Stepper (5:1) | 0.50 µm | ± 0.15 µm | Requires 5" or 6" reticles. High throughput. |
| Contact Aligner (1:1) | ~2.0 µm | ± 1.0 µm (Front) | Supports Backside Alignment (BSA). |
| Direct Write (Maskless) | 0.70 µm | ± 0.50 µm | Ideal for prototyping. No physical mask required. |
Thermal Processing
High Temperature (>800°C)
LPCVD & Oxidation
- Processes: Thermal Oxide, Stoichiometric Nitride, Poly-Si.
- Restriction: Class 1 materials ONLY. No metals. No glass.
- Required Clean: RCA Clean immediately prior to loading.
Low Temperature (<400°C)
PECVD, ALD, & PVD
- Processes: PECVD Oxide/Nitride, ALD Al2O3, Sputtered Metals.
- Flexibility: Compatible with wafers containing metals (in specific tools) and photoresist (for liftoff).
- Stress: Films typically have higher stress than LPCVD equivalents.
Unsure if your process fits our constraints?
Submit Process Review Request