A researcher in a cleanroom suit in the integrated photonics cleanroom using the ion beam etch and deposition tool
Zepler Cleanrooms

Wet and dry etch

An extensive range of wet and dry etch options that enable processing of silicon, metals, dielectrics, III-V, and more unusual materials.

About our etching capability

Part of the nanofabrication cleanrooms

We have an extensive range of wet and dry etch options that enable processing of silicon, metals, dielectrics, III-V, and more unusual materials.  

Our wet benches can handle from small samples to 25x200 millimetre (mm) wafer batches for etching, cleaning, or stripping.  

Hydroflouric acid (HF) and xenon difluoride (XeF2) vapour etching allows isotropic stiction free release of suspended structures and sillicon on Insulator (SOI) dice from up to 200mm wafers.  

We achieve high-resolution pattern transfer features down to the nanoscale, by utilising reactive gas chemistry and plasma etch technology.

Wet etching provides a simple and cheap method of pattern transfer after lithography. 

A researcher in a cleanroom suit uses an Inductively Coupled Plasma Etcher
Inductively coupled plasma etcher - Oxford Instruments ICP380

 

Processes and equipment

Dry etching

 

  • dry etch experience with silicon (Si), germanium (Ge), silicon on Insulator (SOI), silicon dioxide (SiO2), silicon nitride (Si3N4), silicon carbide (SiC), germanium (Ge), aluminium (Al), gold (Au), titanium (Ti), chromium (Cr), platinum (Pt), gallium nitride (GaN), gallium arsenide (GaAs), sapphire, aluminium dioxide (Al2O3), titanium dioxide (TiO2), hafnium dioxide (HfO2), tantalum pentoxide (Ta2O5), niobium pentoxide (Nb2O5), vanadium dioxide (VO2), indium tin oxide (ITO)
  • reactive ion etching (RIE) processing of all plasma compatible materials, from dice to 200mm wafers; argon (Ar), nitrogen (N2), oxygen (O2), trifluoromethane (CHF3), tetrafluoromethane (CF4), and sulphur hexafluoride (SF6) gases available
  • inductively coupled plasma reactive ion etching (ICP-RIE) processing of all plasma compatible materials, from chips to 200mm wafers. Ar, N2, O2, CHF3, CF4, octofluorocyclobutane (C4F8), SF6, silicon tetrafluirode (SiCl4), hydrogene bromide (HBr) and chlorine (Cl2) gases available
  • argon ion beam etch (IBE) using processing of non-volatile materials, from chips to 200mm wafers. CHF3 reactive ion beam etch (RIBE) and chemically assisted ion beam etch (CAIBE) modes

 

Wet etch and cleaning

 

  • wet benches for etching, cleaning, and stripping applications
  • cassette processing tanks for 50 to 200mm substrates
  • silicon (Si) etching by potassium hydroxide (KOH) and tetramethylammonium hydroxide (TMAH) (up to 25x200mm)
  • silicon dioxide (SiO2) etching by 7:1 or 20:1 buffered oxide etchant (BOE) solutions (up to 25x200mm)
  • silicon nitride (Si3N4) etching by phosphoric acid (H3PO4) heated bath (up to 25x150mm)
  • metals: commercial etchants for Al, Au, Ti, and Cr (up to 200mm)
  • metal dielectrics: commercial etchants for chromium dioxide (Cr2O3), Al2O3, TiO2 (up to 200mm)
  • fuming nitric acid (FNA) for organic cleaning (up to 150mm)
  • solvent bench and flexible acid bench for general chemical processes, piranha cleaning, and custom beaker work
  • standard clean 1 and 2 (SC1/SC2) up to 25x200mm

 

Vapour phase etching 

 

  • hydrofluoric vapour phase etching (HF-VPE), SiO2 etching for micro-electromechanical systems (MEMS), SOI and chip release applications, up to 200mm wafers
  • xenon diflouride (XeF2) isotropic dry etching of Si, up to 200mm wafers

 

A researcher in a cleanroom suit using the acid wet benches in the nanofabrication cleanroom
Acid wet benches

 

Contact us

For more information or to book the facilities, get in touch: zepler.cleanrooms@soton.ac.uk