Oxford Instruments Plasmalab System 100 ICP-RIE etch system

Where the Plasmalab System 100 fits

The Oxford Instruments Plasmalab System 100 is a single-wafer, load-locked etch platform, most often built with an inductively coupled plasma (ICP) source above an independently biased lower electrode. That split lets you set plasma density and ion energy separately, which is why a used Plasmalab 100 ICP is a common choice for anisotropic etching of silicon, dielectrics, III-V compounds and metals in research cleanrooms. The platform was later succeeded by the PlasmaPro 100, which shares much of the concept.

Configurations vary widely. The same frame was sold with ICP65, ICP180 and ICP380 sources, with standard, heated or cryogenic tables, and with gas pods for fluorine or chlorine chemistry. Two units with the same name can do very different jobs, so we start every enquiry with your materials and wafer size.

In practice, the source size follows the wafer and the chemistry follows the material. Many ICP180 and ICP380 tools in university facilities are set up for 100 mm wafers, with 150 mm on request, and the larger source gives more rate and uniformity margin. Chemistry is set by the gas pod rather than the source: fluorine gases such as SF6, C4F8, CHF3 and O2 for silicon and dielectrics, chlorine gases such as Cl2 and BCl3 with Ar for III-V compounds and aluminium, and SF6 with O2 on a cryogenic table for cryo silicon etching.

If you are still deciding between ICP and parallel-plate RIE, our post on ICP versus RIE for a university cleanroom sets out the trade-offs.

What we inspect

On a used Plasmalab 100 we look at:

• Chamber and liner: deposits, corrosion from chlorine chemistries and the state of the ceramic and quartz parts.
• ICP source and matching: generator output, match tuning and arcing marks.
• Lower electrode: clamping, helium backside cooling and leak rate, temperature control.
• Load lock and transfer arm: alignment and repeatable wafer placement.
• Vacuum system: turbo pump hours, backing pump type and base pressure.
• Gas pod: mass flow controllers, valves and leak integrity per line.
• Control system: PC, software version and stored recipes.

Results go into the report with photos and the measured base pressure and leak-up rate.

Refurbishment and upgrades

A refurbished unit gets a chamber refurbishment: stripped, cleaned, new seals and consumables, re-assembled and leak-checked. We service or replace the turbo pump, check the RF chain and calibrate the mass flow controllers. Certified units run a test etch with rate and uniformity in the report.

The upgrades we fit most often are a dry pump conversion, which removes oil back-streaming and is close to essential for chlorine work, and optical endpoint detection for etches that must stop on a thin layer.

Facilities

• Three-phase power, depending on configuration
• Process cooling water for generators, turbo and electrode chiller
• Clean dry air and nitrogen for valves and venting
• Process gas lines, toxic gas cabinets for chlorine chemistries
• Exhaust, with a scrubber or abatement where your site requires it
• Liquid nitrogen supply for cryogenic tables

Buying advice

Match the source, table and gas pod to your process before looking at condition, because changing them later is expensive. Ask for the leak-up rate and turbo hours. Check that toxic gas safety interlocks and gas detection at your site cover the chemistries the tool will run. The etch category compares this platform with the other etchers we handle.