Southampton Nanofabrication Centre

Dry Etching

The SNC has an extensive range of dry etch systems for various research interests in silicon processing, metal etching, dielectric machining, thin film processing and other semiconductor materials (Type II, III, V, and N). High resolution pattern transfer features from micron to nano scale is done through reactive gas chemistry and plasma etch technology. There are six machines based in the main cleanroom:

RIE - Reactive Ion Etching

The etch mechanism of RIE is achieved by using the reactive gas plasma generated by strong RF source (13.56 MHz) to chemically ion etch the material of the samples. Depending on the process recipe, the material's etched profile can achieve high anisotropy. There are two Plasmalab systems:

  • Plasmalab 80 plus - Fluorine-based chemistry etching, alternatively argon and oxygen. Ideal for silicon (amorphous, poly), silica, silicon nitride, polymer, metal and resist residue cleaning.
  • Plasmalab 80 plus - Chlorine-based chemistry etching. Ideal for metal etching and suitable for III-V semiconductor materials.

ICP - Inductively Coupled Plasma Etching

The etching plasma is created by an RIE RF source and RF induction magnetic coil to produce high plasma densities. The results are high etch rate, high aspect ratio, and anisotropic etching of material of the samples. In addition, the systems can operate in ICP or RIE mode separately. The ICP systems are:

  • Plasmalab System 100 - Fluorine-based chemistry etching. Ideal for deep oxide etching, BPSG, TEOS, rare earth oxide, poly-silicon, polymer and diamond based material.
  • Plasmalab System 100 - Chlorine/bromine-based chemistry etching. Ideal for metal etching, poly-silicon gate, platinum, III-V and III-N based semiconductor materials.

RIBE - Reactive Ion Beam Etching

Working on the similar principle as the reactive ion etcher but is assisted by an energised ion beam for the etching mechanism. This can achieve very high aspect ratio profiles, high etch rate and uniformity over a large sample. The system can handle up to 200 mm diameter wafer and sample can be tilted to perform angular etch.

  • Ionfab 300 plus - Configured for MEMS and NEMS structures, silicon-based material, silica, quartz and deep etch structures.

DSE - Deep Silicon Etcher

This system utilises the Advanced Silicon Etch (ASE) Technology, based on the Bosch process, to achieve very deep silicon etch profile and smooth sidewall. This etching process is particularly suitable for silicon-based MEMS and NEMS devices where anisotropic profiles are essential.

  • STS LPX Pegasus - Configured for fluorine-based chemistry to etch silicon-based materials.