Varian E220 medium-current ion implanter

Where a used Varian E220 makes sense

The Varian E220 belongs to the generation of medium-current implanters that moved from operator-driven machines to automated, recipe-based tools. For a pilot line or a university fab with many users, that matters more than raw specification: wafers load from cassettes, recipes are stored, and the dose is integrated and logged without an operator watching meters. A refurbished E220 covers the classic medium-current jobs, such as threshold-adjust, well and lightly doped drain implants, at energies up to about 200 keV.

Buyers usually compare it with the older Varian 350D and with other tools in our ion implantation range. The E220 wins on throughput and repeatability; the 350D wins on simplicity and a smaller set of electronics to keep alive.

Wear points we look for

Implanters age in predictable places, and the E220 is no exception.

The ion source is the main consumable. Filaments, arc chambers, repellers and extraction parts erode with use, and the rate depends heavily on which species were run. Next come the vacuum pumps: cryopumps on the beamline and end station lose capacity, and their compressors need service at fixed intervals. On the high-voltage side we look for tracking on insulators and check that supplies reach full voltage without arcing.

The end station deserves its own check. Wafer handling robots, platen seals, tilt and twist mechanisms and wafer-present sensors all wear, and a handling fault in a cassette run is what users notice first. We cycle the handler with test wafers and log every mis-pick.

How we refurbish an E220

Work starts with decontamination of source housing, beamline and pump parts, under procedures for arsenic and phosphorus residues. We then:

1. Rebuild the source with new consumables and clean or replace extraction electrodes.
2. Overhaul or exchange cryopumps and roughing pumps, and leak-check the full vacuum system.
3. Test the high-voltage supplies, analyser magnet supply and scan system under load.
4. Repair or replace control boards that fail testing, and back up the tool software.
5. Verify dose measurement and, for a Certified grade, implant and map test wafers.

Keeping it running

An E220 rewards a planned preventive maintenance schedule: source rebuilds by beam hours, cryopump regenerations and compressor service by calendar, and annual checks of interlocks and radiation surveys. Unplanned downtime on older implanters usually traces back to deferred pump service or a board that was never backed up.

Facilities for installation

Figures depend on configuration; we send the checklist for your unit.

• Three-phase power for the supplies, magnet and pumps
• Process cooling water
• Compressed dry air and nitrogen
• Toxic gas cabinet or approved storage for dopant sources, with gas detection
• General and toxic exhaust
• A room that meets your local radiation and high-voltage safety rules

Before you buy

Confirm the wafer size fitted to the end station, the species history and whether the tool software and its licence came with the unit. If you are weighing 150 mm against 200 mm for a pilot line, our article on 150 mm vs 200 mm tools sets out the trade-offs.