Tired of full replacement costs every PM cycle? Not sure if refurbished ESCs are safe to run?
OHI Tech has supplied and refurbished hundreds of ESCs for Lam Research Kiyo, Flex, and Versys tools. We have directly verified which condition still qualifies for refurbishment and when new parts are truly required. Here are those criteria.
Bottom Line: Refurbished ESCs Match New-Part Performance
OHI Tech-certified refurbished ESCs meet the same clamping force, insulation resistance, and particle specs as new parts — at a significantly lower cost than new.
Exception: ceramic surface cracks or gas hole blockage above 20% cannot be refurbished and require new-part replacement.
Johnsen-Rahbek vs Coulomb Type: Side-by-Side
| Parameter | Johnsen-Rahbek (J-R) | Coulomb |
|---|---|---|
| Clamping mechanism | Dielectric leakage current | Pure electrostatic force |
| Applied voltage | 200–600V | 1–2kV |
| Clamping force | High (30–80 Torr) | Medium |
| Dechuck speed | Slightly slow (residual charge) | Fast |
| Primary tools | Lam Kiyo, Flex, Versys | AMAT, TEL (select models) |
| Ceramic material | AlN, Al₂O₃ (semiconducting) | Al₂O₃ (insulating) |
ESC Specs by Tool
| Tool | Type | Diameter | Key Features |
|---|---|---|---|
| Lam Kiyo | J-R | 300mm | High-density plasma, varied gas hole patterns |
| Lam Flex | J-R | 300mm | Low-pressure etch, RF applied |
| Lam Versys | J-R | 300mm | Small feature etch, high selectivity |
| AMAT Centura | Coulomb | 200/300mm | Multi-layer electrode |
| TEL Trias | J-R | 300mm | High-temp process, AlN base |
OHI Tech Refurbishment Qualification Criteria
These are the exact criteria OHI Tech applies when deciding whether an ESC can be refurbished.
Refurbishable — all 5 must pass:
- Surface roughness (Ra): ≤0.8μm
- Insulation resistance: ≥10⁹Ω at 500V DC
- Clamping force: ≥80% of new-part spec
- Particle generation: within class spec
- Surface cracks / chipping: none
- Ceramic surface crack or spalling confirmed
- Gas hole blockage ≥20%
- Clamping force <50% of new-part spec
Refurbishment Results
OHI Tech-qualified refurbished ESCs meet the same clamping force, insulation resistance, and particle specifications as new parts. Specific supply case details are available upon request.
FAQ
Q1. What warranty comes with refurbished ESCs? Warranty coverage depends on the part condition and refurbishment scope — details are provided upon inquiry. All refurbished ESCs come with a performance data report covering measured clamping force, insulation resistance, and particle count.
Q2. How long does refurbishment take? Turnaround time depends on the part condition and refurbishment scope. We assess the unit on receipt and provide a timeline estimate based on the diagnosis result.
Q3. Can you supply ESCs for tools other than Kiyo, Flex, and Versys? Yes — AMAT, TEL, and other tool ESCs are available. Send us the tool model and ESC part number and we will confirm availability for new supply or refurbishment. Contact: jino.kim@ohitech.co.kr