Wafer Dicing (Step 2)
Dicing is the process of cutting a finished wafer into individual dies (chips) after wafer sort. Each die is then separated and prepared for assembly and packaging. Dicing is a precision mechanical and/or laser process that must balance throughput, accuracy, and defect control, as chips are increasingly small and fragile at advanced nodes.
Process Overview
- Purpose: Separate a processed wafer into individual functional dies for packaging.
- Techniques: Mechanical blade dicing, laser dicing, and stealth dicing.
- Sequence: Wafer is mounted on dicing tape ? aligned ? cut by blade or laser ? dies remain on tape for pickup.
- Integration: Performed after wafer testing; only good dies are selected for packaging.
Dicing Methods
| Method | Process | Advantages | Constraints |
|---|---|---|---|
| Blade Dicing | Diamond-coated circular blade cuts wafer along scribe lines. | Proven, high throughput, widely used. | Mechanical stress; chipping risk; kerf width consumes wafer area. |
| Laser Dicing | Focused laser beam ablates material along scribe lines. | Narrow kerf, low mechanical stress, suited for thin wafers. | Heat damage risk; slower for thicker wafers. |
| Stealth Dicing | Laser modifies wafer internally, followed by mechanical separation. | Minimal debris, narrow kerf, good for brittle materials. | Specialized equipment; integration complexity. |
Major Equipment Vendors
- DISCO Corporation (Japan): Market leader in dicing saws, laser, and stealth dicing systems.
- ADT (Advanced Dicing Technologies, Israel): High-precision dicing saws and accessories.
- Synova (Switzerland): Hybrid laser-water jet dicing systems (Laser MicroJet).
- Tokyo Seimitsu (Accretech, Japan): Wafer dicing saws and metrology tools.
Process Consumables
- Dicing Blades: Diamond-coated blades with varying grit sizes.
- Dicing Tape: Adhesive films that secure wafer during cutting.
- Coolants & Water: Used to reduce heat and debris in blade dicing.
- Protective Coatings: Optional temporary films to protect wafer surfaces.
Cleanroom & Environment
- Dicing is typically performed in Class 1000 or less stringent environments, unlike FEOL steps.
- Water and debris control is critical to avoid die surface contamination.
- Die yield depends on minimizing edge chipping, cracks, and particle defects.
Advantages & Constraints
- Advantages: Enables high-volume separation of wafers into dies; multiple dicing methods available for different materials and thicknesses.
- Constraints: Wafer thinning and fragile advanced-node dies increase breakage risk; consumables cost (blades, tape) can be significant.
Market Outlook
As wafer sizes grow (300 mm and beyond) and dies become thinner for advanced packaging, demand for precision dicing technologies is increasing. Laser and stealth dicing adoption is rising in high-performance, automotive, and 3D packaging markets, while blade dicing remains the workhorse for legacy and mid-range devices.