ZYGO ZMI-2002-8020-0211-1-J — Dual‑Axis Laser Interferometer Measurement Module for Precision Motion

The model ZMI‑2002 (part no. 8020‑0211‑1, Rev J) is a ZYGO interferometer electronics module widely used in high‑accuracy motion systems where nanometer‑level position feedback is required. From my experience, it’s the go‑to replacement when a dual‑axis channel is needed for precision stages, metrology fixtures, or for keeping legacy ZMI 2000‑series installations running reliably with minimal requalification.

Company’s Order Placement Process and Guarantees

• Warranty: 365 days
• Delivery: 1 week if in stock; no more than one month at the latest
• Payment: 50% advance payment, full payment before delivery
• Express options: FedEx, UPS, DHL

Key Features

• Dual‑axis interferometer processing – Typically handles two measurement channels for X/Y or X/θ applications, keeping controller integration straightforward.
• Nanometer‑class resolution – Designed for high‑precision motion feedback; users usually see stable, low‑noise counts in controlled environments.
• Quadrature outputs for motion controllers – Differential RS‑422 A/B/Z signals in many cases, so existing servo controllers read it like a high‑resolution encoder.
• Drop‑in for ZMI 2000‑series racks – Slides into the ZMI chassis; no external PSU or custom brackets in typical setups.
• Stable metrology performance – Built for long‑term drift stability, which helps during extended litho, inspection, or alignment runs.
• Proven in semiconductor and precision optics – Commonly used where positional repeatability and traceability really matter.

Technical Specifications

Application Fields

You might notice that this module shows up wherever high‑end positioning is the bottleneck. Typical uses include:

• Semiconductor lithography and wafer inspection stages
• Precision optics alignment, interferometric testing benches
• Coordinate measuring machines and ultra‑precision machine tools
• Laser micromachining, MEMS motion systems, and research labs
• Retrofits where encoder‑like outputs from a laser interferometer are preferred

Advantages & Value

• Reduced integration risk – Keeps existing ZMI racks and controller interfaces intact; typically no rework on motion IO.
• High stability – Consistent counts over long runs help maintain tool overlay and repeatability.
• Serviceability – Easy module swap minimizes downtime; many teams keep a spare to cut recovery time to minutes.
• Lifecycle support – Useful for sustaining legacy ZMI platforms that are still validated in production flows.
• Cost control – Extends the life of installed interferometer heads, cabling, and motion controllers.

A precision optics customer told us they “dropped it into a ZMI rack and were back collecting nanometer‑stable data before lunch,” which—while not glamorous—saves a shift of lost metrology time.

Installation & Maintenance

• Cabinet & environment – Install in a ZMI 2000‑series chassis within a clean, temperature‑controlled area (typically 15–30 °C). Ensure front‑panel airflow isn’t obstructed.
• Wiring – Use the specified shielded cables; keep interferometer and quadrature lines separate from high‑power motor wiring to reduce noise coupling.
• ESD & handling – Observe ESD precautions when inserting/removing the module; seat firmly until the latches engage.
• Calibration – Verify scale factors and reference offsets after installation or when environmental conditions change.
• Routine checks – Periodically inspect connectors for contamination; clean with appropriate optics‑safe methods if fiber or optical connections are present.
• Firmware/parameters – Where applicable, back up configuration and update firmware only under controlled change procedures.

Quality & Certifications

• CE and RoHS compliant in typical configurations
• Manufactured under ISO 9001 quality systems
• Warranty: 12 months (365 days) from delivery