Semitool PSC-101 spin rinse dryer

Where the Semitool spin rinse dryer fits

Most wet benches in a university cleanroom end at a spin rinse dryer, because wafers must leave the last rinse clean, dry and free of water marks. Semitool, later acquired by Applied Materials, built these stacks in single- and double-chamber versions for whole cassettes of wafers or masks. A used Semitool spin rinse dryer is one of the lowest-risk tools you can buy refurbished: the mechanics are simple, parts are common and the process is easy to verify.

The tool rinses a full cassette with DI water, checks the rinse water resistivity to confirm the wafers are clean, then spins them dry under heated nitrogen. That gives a repeatable, operator-independent end to RCA cleans, wet etches and resist strips. The benches and single-wafer processors that feed it are listed under wet processing and CMP.

Wear points on a used unit

The parts that wear are the ones that spin or seal.

• Rotor and bearings. Rotors take impacts from mis-loaded cassettes. We check them for cracks and run-out and listen to the bearings at speed.
• Motor, brake and imbalance sensor. A weak brake or drifting sensor causes aborted cycles.
• Door and chamber seals. Leaking seals let water reach the electronics and shorten the life of the controller.
• Resistivity cell. Fouled or drifting cells make the rinse step run long or pass too early.
• Nitrogen heater and filter. A failed heater leaves water spots; a loaded filter adds particles.
• Controller. We check the display, keypad and stored recipes on the PSC-101 and confirm all steps run.

Refurbishment

A refurbished unit gets new seals and bearings, a cleaned and inspected rotor, a tested or replaced resistivity cell, new nitrogen filters and a functional check of every recipe step. We run test loads with dummy wafers at full speed, check balance and dry results, and report particle performance if you need it for acceptance.

When an installed dryer fails, our repair and troubleshooting service covers diagnosis and parts. Most faults on these units are mechanical and are repaired in a short visit.

Changing wafer size

Moving from 100 to 150 mm, or adding mask drying, usually needs only a new rotor and matching cassettes. On a double stack you can keep one chamber at each size. We handle this as a small wafer size conversion, including the recipe changes for the new load.

Facilities

• Single-phase power, voltage depending on the unit
• DI water supply, ideally from a loop with resistivity close to 18 MΩ·cm
• Filtered nitrogen at the pressure set by the controller configuration
• Drain for rinse water
• Exhaust connection to the chamber

Buying advice

Ask which cassette rotors come with the unit, whether it is single or double stack, and the supply voltage. Ask too what it dried: a unit that saw only water-rinsed loads is usually in better shape than one exposed to solvent residues. If you are weighing a refurbished dryer against a new one, our article on used vs refurbished vs new equipment sets out the cost and risk trade-offs.