Edge Grinding
edgeGrinding.desc
Overview
Edge grinding transforms the as-sawn or as-lapped wafer edge into a precision-machined, beveled profile meeting SEMI M1 standards. Without proper edge treatment, wafers generate particle contamination, experience chipping into active device areas, and risk fracture during thermal processing.
GINECHIP addresses the full spectrum: bullet/symmetric profiles for robotic handling, T-type flat-apex profiles for large-die applications, precision notch/flat machining to SEMI M1, and post-grind edge polishing. Our multi-step process — coarse grind → fine grind → polish → clean — delivers measurable yield improvement.
Edge Grinding Services
Bullet / Round Profile Grinding
Symmetric bullet/round edge profile per SEMI M1. Edge radius 200–400μm. > 90% chipping reduction. Optimized for robotic handling. 100–300mm wafers.
T-Type / Flat Apex Profile
Flat apex T-type profile maximizing usable wafer area. Edge exclusion down to 1mm. Optimized for large-die and image sensor applications. Precision diamond grinding with profile metrology.
Notch & Flat Grinding
SEMI M1 compliant notch (1.00 ± 0.25mm, 90° ± 5°) and flat machining. Primary and secondary flats for orientation and dopant type identification.
Edge Polishing
Post-grind CMP edge polishing achieving Ra < 0.1μm. > 80% particle reduction. Enhanced epi deposition quality. Improved bonding interface.
Chamfering & Custom Profiles
Chamfer angles 15°–45°, width controlled to ±25μm. Thin-wafer and 3D-IC/TSV optimized. Custom profiles per specification.
Edge Grinding Process Flow
Incoming Inspection & Metrology
Optical comparator and laser profilometry of as-received edge. Documentation of edge condition. Lot traceability assignment.
Coarse Grinding (Rough Profiling)
Diamond wheel grit 800–1,200 removes bulk material. High MRR with controlled feed. DI water coolant. In-process optical monitoring.
Fine Grinding (Precision Finishing)
Finer diamond wheel grit 2,000–4,000 refines surface. Reduced feed rate. Edge radius and chamfer verified via in-line laser profilometry.
Notch & Flat Machining
Dedicated notch and flat grinding tooling. SEMI M1 profile: 1.00 ± 0.25mm depth, 90° ± 5° angle. Controlled flat width and angular orientation.
Edge Polishing
CMP or mechanical edge polishing with cerium oxide or colloidal silica slurry. Removes sub-surface damage. Ra < 0.1μm. Post-polish optical inspection.
Cleaning & Final Inspection
Megasonic cleaning to remove swarf and residues. Final edge profile verification. Surface roughness measurement. Documentation and packaging.
Edge Grinding Quality Specifications
| Parameter | Target Specification | Measurement Method |
|---|---|---|
| Edge Radius | 200–400μm (bullet) | Laser Profilometer |
| Chamfer Angle | 15°–45° ± 1° | Laser Profilometer |
| Edge Exclusion | < 1mm (T-type), < 3mm (bullet) | Optical Comparator |
| Edge Roughness (Ra) | < 0.1μm (polished), < 0.5μm (ground) | AFM / Optical Profiler |
| Notch Depth | 1.00 ± 0.25mm | Optical Comparator |
| Notch Angle | 90° ± 5° | Optical Comparator |
| Edge Chipping | < 0.3mm depth, < 3/10mm density | Optical Microscope |
| Particle Adders | < 10 @ 0.2μm (post-clean) | Wafer Surface Scanner |
All specifications verified per lot. Full metrology report and Certificate of Conformance included.
Edge Profile Selection Guide
Bullet / Symmetric Profile
The bullet profile is the industry-standard symmetric edge contour (SEMI M1). Smoothly radiused from frontside to backside, maximizing robotic handling reliability. Edge radius: 200–400μm typical.
T-Type / Flat Apex Profile
The T-type profile features a flat apex with chamfered transitions, maximizing usable wafer area by minimizing edge exclusion. Critical for large-die applications (image sensors, power devices).
Edge Quality & Inspection Standards
Edge Chipping Control
Edge chipping is the primary defect mode. Our grinding process reduces chipping by > 90% relative to as-sawn edges. Classified per SEMI M1:
Edge Particle Generation
A poorly ground wafer edge is a significant source of particle contamination. Our polished edge finish achieves:
Thin Wafer Edge Grinding
Wafers thinner than 200μm present unique challenges: reduced stiffness increases fracture risk, thermal effects induce warpage. Our process uses reduced forces, optimized wheel grit, and in-line monitoring to safely process down to 50μm.
For ultra-thin wafers (50–100μm), we offer supported grinding with temporary bonding to a rigid carrier, eliminating stress concentration at the edge.
Notch & Flat Grinding
Notches ground to SEMI M1 (1.00 ± 0.25mm depth, 90° ± 5° angle). Primary/secondary flats with controlled width and angular orientation. Secondary flat identifies dopant type per SEMI M1 standards.
Edge Inspection & Metrology
Every ground edge undergoes three-tier inspection: (1) optical microscopy 50–200× for defect detection, (2) laser profilometry for quantitative profile measurement, (3) AFM for surface roughness. Full metrology report with each shipment.
Need Precision Edge Grinding?
Specify your wafer diameter, target edge profile, and quantity — our team will respond with a detailed quotation within 24 hours.