Diamond Wire Cutting for Glass and Brittle Materials

What Is Diamond Wire Cutting?

Diamond wire cutting is a precision slicing process in which a thin steel wire coated with electroplated or resin-bonded diamond abrasive particles is drawn continuously across the workpiece surface under controlled tension and feed rate, removing material through abrasive grinding action. The wire — typically 0.1 to 0.4 mm in diameter — travels at high speed (10 – 30 m/s) while the workpiece is fed slowly into the cutting plane, producing a slice with a kerf width only slightly larger than the wire diameter itself. Because the wire is extremely thin compared to conventional cutting tools, diamond wire cutting achieves the narrowest possible kerf among all contact cutting methods, minimizing material loss — a critical advantage when processing expensive substrates such as sapphire, optical crystals, and high-purity fused silica. Multi-wire configurations allow dozens of parallel slices to be produced simultaneously in a single pass, dramatically increasing throughput for wafer and plate production.

Process Capabilities

• Wire Diameter: Ø0.10 – 0.40 mm (electroplated or resin-bonded diamond)
• Kerf Width: 120 – 450 µm (wire diameter + diamond layer)
• Minimum Slice Thickness: 0.3 mm (single wire); 0.5 mm (multi-wire)
• Thickness Tolerance: ±20 µm (standard); ±10 µm (precision)
• Surface Roughness (Ra): 0.5 – 2.0 µm (as-cut); ≤ 0.1 µm (post-lapped)
• Maximum Workpiece Size: Ø300 mm × 400 mm length
• Multi-Wire Capacity: Up to 100 simultaneous slices per pass

Compatible Materials

Edge Quality & Finish

• As-Cut Ra: 0.5 – 2.0 µm (electroplated wire, fine grit); 1.0 – 3.0 µm (resin-bonded)
• Sub-Surface Damage Depth: 5 – 20 µm (removable by lapping)
• Warp: ≤ 20 µm per 100 mm diameter (tension-controlled cutting)
• TTV (Total Thickness Variation): ≤ 15 µm (standard); ≤ 5 µm (precision)
• Edge Condition: As-cut; optional chamfer and edge grinding available
• Post-Process Options: Double-sided lapping, polishing, AR coating, wafer inspection

Typical Applications

• Sapphire Wafer Slicing: C-plane and A-plane sapphire boules sliced to LED and SiC substrate wafers
• Optical Crystal Blanks: CaF₂, Ge, and scintillator crystal slicing for detector and lens blanks
• Silicon Ingot Wafering: Mono and polycrystalline silicon slicing for solar and semiconductor
• Quartz Crystal Plates: AT-cut and BT-cut resonator blanks from synthetic quartz bars
• Fused Silica Plates: High-purity substrate plates for lithography and semiconductor tooling
• Glass-Ceramic Slabs: ZERODUR mirror substrate blanks for precision optics and metrology

Custom Specifications

We accept custom diamond wire cutting orders for both boule-to-wafer and block-to-plate slicing, with full support for customer-supplied or in-house sourced raw material. Custom parameters include wire diameter selection, grit size, slice thickness, multi-wire pitch, and cutting fluid formulation for specific material compatibility. Integrated post-slicing services — including double-sided lapping, polishing, edge grinding, wafer inspection (TTV, warp, bow), and packaging in cleanroom-compatible carriers — are available as a complete substrate preparation workflow. All sliced substrates are delivered with full dimensional and surface quality documentation.

Kerf Loss Comparison: Cutting Method vs Material Loss

Kerf width and material loss per cut across four slicing methods — sapphire reference (Mohs 9) 0 500 1000 1500 2000+ Kerf Width / Material Loss per Cut (µm) Diamond Wire Cutting 120 – 200 µm ✓ Material yield: ~85% Abrasive Slurry Wire Saw 300 – 500 µm Material yield: ~65% Inner Diameter (ID) Saw 400 – 800 µm Material yield: ~55% Abrasive Waterjet 800 – 1500 µm Material yield: ~40% Up to 60% less waste Cost Impact Sapphire: ~\$50/cm³ Narrower kerf = direct saving Diamond Wire Cutting (this process) Alternative Methods