Reactive Ion Etching (RIE)

Deep anisotropic silicon etching up to some tens of µm, etching of SiC and surface cleaning  of different materials in oxygen can be carried out using fluorine containing gases with the SENTECH reactive ion etching tool.

Sentech SI 500

Type Single chamber parallel plate reactor
Specifications Process chamber Inner diameter 300 mm, 270 mm high, with Laser-interferometer Etch-stop
Electrodes Upper electrode with gas shower, 250 mm diameter
Substrate electrode for up to 200 mm wafers with three lifting pins, cooled or heated in the temperature range -30 < T(°C) < 80
RF-supply ICP source up to 1200 W, RF source up to 800 W, frequency 13.56 MHz
Load lock Automatic single wafer pneumatic vacuum load lock
Gas flow 8 channels (SF6, CF4, O2, Ar, C4F8 with MFC controlling)
Operating mode Automatical mode with SPS controlling coupled to a PC, SENTECH software
Current applications Anisotropic etching of SiC using SF6+O2 or CF4+O2, etch rate 40 nm/min, usual etch depth up to 200 nm, with metal masks
Anisotropic etching of Si using SF6+O2 and thermally grown SiO2 as etch mask, etch rate 1 µm/min, etch depth of trenchs < 20 µm, selectivity RSi/RSiO2 > 130.
Anisotropic etch of Si with SF6 + C4F8 using photoresist or HSQ masks, etch rate of 1.2 µm/min, seletivity of 25 for S1800 PR mask, 90° sidewalls
Faraday cage assisted etching (FCAE), angles faraday cage to influence ion incidence angle on etched structures