LONGYI · WAFER INSPECTION & HANDLING · MADE IN TAIWAN
Wafer Work Chuck8″ & 12″ Porous Alumina Vacuum Chuck, Flat to 0.005 mm
The chuck that holds a 200 mm or 300 mm wafer perfectly flat for inspection, metrology, dicing, grinding fixtures and handling. Concentric porous zones grip the entire wafer face, a 96% alumina porous plate gives smooth, mark-free suction, and a rigid 99.5% alumina frame keeps flatness and parallelism at 0.005 mm.
The LONGYI Wafer Work Chuck is a 96% alumina porous ceramic vacuum chuck for 8″ and 12″ semiconductor wafers. Multi-zone porous suction holds the whole wafer flat to 0.005 mm. Available as 8″ (CPC-AL99-08), 12″ (CPC-AL99-12) and dual 8″ & 12″ (CPC-AL99-0812) models, each built to your stage drawing.
Hold the Whole Wafer — and Only the Wafer
Each porous zone sits over its own vacuum chamber and its own vacuum line. Switch a zone ON when the wafer covers it, OFF when it does not. Watch the same chuck hold a 12″ wafer and an 8″ wafer.
Large wafer: open every zone
The 12″ wafer covers both the Ø200 inner zone and the outer ring. Both vacuum lines are ON, so air is drawn down through every pore into each zone's own chamber and out through its own line.
Small wafer: switch the outer ring off
The 8″ wafer covers only the inner zone. The outer ring has a separate chamber and line, so it is switched OFF — no exposed pores bleed air, and the wafer is held at the same vacuum. One chuck, both sizes, no tooling change.
One Porous Ceramic, Engineered for Each Station
The wafer work chuck is tuned for flatness and a smooth hold. The rest of the family is built for grinding, dicing, general work holding and air bearings.
From Wafer Size to a Chuck That Fits
Scroll through the five decisions behind every LONGYI wafer work chuck.
Wafer Size & Model
8″ (CPC-AL99-08), 12″ (CPC-AL99-12), or the dual CPC-AL99-0812 that holds both on one plate with nested zones.
Porous Plate: 96% Alumina, 10–15 µm
Fine pores and 40–45% porosity give stable, leak-free suction and a smooth hold that leaves no marks on thin wafers.
Flatness & Parallelism: 0.005 mm
The wafer sits in one focal plane for inspection and metrology, and the chuck seats true on your stage for repeatable placement.
Stage Interface & Ports
Outer diameter, porous zone pattern, mounting PCD and hole layout are taken from your drawing. Standard M5×0.8 top and G1/8″ backside vacuum ports.
Verification
Every drawing is reviewed before machining, and critical dimensions are 100% inspected before the chuck ships.
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8″, 12″ or Both on One Chuck
Three standard models share the same porous alumina and the same 0.005 mm flatness. Each is then adapted to your stage — download the dimensional drawing as a starting point.
8″ Wafer Work Chuck — CPC-AL99-08
Porous ceramic vacuum chuck for 200 mm (8-inch) wafers. Multi-zone suction with 0.005 mm flatness, sized and ported to your inspection, dicing or handling stage.
12″ Wafer Work Chuck — CPC-AL99-12
Porous ceramic vacuum chuck for 300 mm (12-inch) wafers. Larger concentric porous zones grip the full wafer for warpage-free holding on metrology and process equipment.
8″ & 12″ Dual Wafer Work Chuck — CPC-AL99-0812
Holds both 8-inch and 12-inch wafers on a single plate with nested porous zones — ideal for mixed-size lines and shared stages.
Material Properties & Build
Common to all three models. Values are for the standard build and are confirmed on the approved drawing before production.
| Item | Value / Capability |
|---|---|
| Product Type | Porous ceramic vacuum chuck for 8″ and 12″ semiconductor wafers — inspection, metrology, dicing, grinding fixtures and handling. |
| Porous Ceramic Grade | C#-200 / B-200 — common to all three models. |
| Porous Plate | Alumina (Al₂O₃) 96%, black |
| Frame | Alumina 99.5% — rigid under vacuum load and thermal cycling. |
| Pore Size | 10–15 µm — fine enough for a smooth, mark-free hold on thin wafers. |
| Porosity | 40–45% open porosity for stable, even suction. |
| Bulk Density | 2.28 g/cm³ |
| Flatness | 0.005 mm |
| Parallelism | 0.005 mm |
| Vacuum Ports | Standard M5×0.8 top port and G1/8″ backside pipe-thread port; other threads to spec. |
| Electrical | Standard PC is insulative; anti-static (ATC, 10⁶–10⁹ Ω) option for static-sensitive processes. |
| Customisation | Outer diameter, porous zone pattern, mounting PCD and hole layout, port threads — all to your drawing. |
Key Features
Material Options
Built from LONGYI porous alumina; material and porosity tuned to your suction and flatness requirements.
Built to Your Equipment's Drawing
Tell us your wafer size, stage interface and vacuum layout — we tune the design to your process.
Custom outer diameter
Sized to your stage envelope.
Custom porous zone pattern
Tuned to your wafer and suction map.
Custom PCD & hole layout
Matched to your mounting interface.
Custom port threads
Top and backside vacuum ports to spec.
ESD option
Anti-static ceramic for static-sensitive processes.
Drawing-based review
Submit PDF / DXF for an engineering check before quoting.
Back grinding needs a different chuck: 100 µm coarse pores, a 15 mm porous body and a 99% alumina frame — CPC-WG-120806 (12″/8″/6″), CPC-WG-080604 (8″/6″/4″) and CPC-WG-08 (8″).
Porous Alumina Wafer Chucks
Representative LONGYI wafer chucks — single-zone and multi-zone builds.
CLICK ANY PHOTO TO ENLARGE →
The Principle, and a Flatness Check
How a porous ceramic chuck holds — and a customer checking one of our chucks on their own machine.
How a Porous Ceramic Vacuum Chuck Works
The same surface does two opposite jobs. Draw air in and the workpiece is held down; push air out and it lifts clear on a film of air.
Wafer Work Chuck FAQ
Common procurement and application questions from process and equipment engineers.
01What is a wafer work chuck?
A wafer work chuck is a porous ceramic vacuum chuck that holds a semiconductor wafer flat during inspection, dicing, grinding and handling. Vacuum drawn through the porous alumina surface grips the entire wafer face instead of a few contact points, preventing warpage and slippage. LONGYI builds 8-inch and 12-inch chucks with flatness held to 0.005 mm.
02Do these vacuum chucks fit our existing wafer stage and equipment?
Yes. LONGYI wafer work chucks are built to match your stage interface, mounting PCD and vacuum port layout, so they integrate with your existing inspection, dicing, grinding or handling equipment. Please provide your stage drawing or equipment model for compatibility confirmation.
03What wafer sizes are supported?
Standard models cover 8-inch (200 mm) and 12-inch (300 mm) wafers. The dual CPC-AL99-0812 model holds both 8″ and 12″ wafers on a single chuck with nested porous zones. Custom diameters are available on request.
04Why does a multi-size chuck need separate vacuum zones?
A porous chuck draws through every pore that is exposed. If a smaller wafer sits on a single-zone larger face, the uncovered ring leaks air and holding force drops. Nested zones separated by dense alumina lands let you open only the zone the wafer covers.
05How flat is the chuck, and how do we maintain it?
Flatness and parallelism are both held to 0.005 mm. The alumina porous surface needs no coating; clean gently with solvents compatible with your process and avoid abrasive tools that could scratch the surface.
06Can we request samples before mass production?
Yes, sample chucks can be provided for trial and process validation prior to volume orders. Please confirm sample cost and lead time with our sales team.
07What is the typical lead time for a custom wafer chuck?
Lead time depends on chuck size, porous-zone pattern and hole-layout complexity. Please contact our sales team for standard and expedited options.
08What do you need from us to quote a custom chuck?
Please provide wafer size, target flatness, stage interface / mounting PCD, vacuum port type and quantity. Customer drawings (PDF or DXF) can be submitted directly for engineering review.
Dimensional Drawings
Engineering drawing for each model — dimensions, porous zones and mounting layout.
Porous Ceramic Vacuum Chuck Catalog
Standard sizes, PC / ATC material options, vacuum zoning and selection guide for the whole chuck family.
↓ Download Catalog (PDF)Also Known As
Depending on the equipment maker, process or region, this component is referred to by several names. They generally describe the same porous alumina ceramic vacuum chuck for holding semiconductor wafers flat during processing:
Need a Wafer Chuck Built to Your Drawing?
Send us your wafer size and stage interface — our engineers will spec a porous ceramic vacuum chuck for your equipment.
LONGYI | Advanced Ceramic Manufacturer
