Capabilities
The Ohio State Nanotech West Lab currently possesses the following capabilities. For semiconductor-related processing, we are capable of handling 100mm (4") wafers down to small parts in all but a very few processes.
Our electron beam lithography capability features a Leica/Vistec EBPG 5000 field-emission electron beam pattern generator (EBL01). The tool can operate at 50 and 100 keV using beam sizes as small as ~5 nm which results in linewidths down to ~20nm. We have in-house CAD layout and data fracturing capability and can accept GDSII, Tanner Database (TDB), and CTEXT formats, among others. Our engineering staff is highly experienced in both industrial semiconductor mix-and-match (e-beam and photo) and research lithography.
Our standard e-beam processes include:
- PMMA 950k (2% and 4%) and PMMA/MAA copolymer
- Bilayer resist processing for robust liftoff
- SU-8 high aspect ratio negative resist
- HSQ high resolution negative resist
- maN 2403 easily removable negative resist
- 4″ and 5″ photomask and reticle fabrication for photolithography
- Staff-assisted CAD layout help is available for simple designs
Our optical lithography capability includes a GCA 6100C I-line stepper, 2 EVG 620 Contact Aligners, and a Karl Suss MJB-3 Contact Aligner. Processes available include:
- I-line (365 nm) stepper photolithography (STP01) to linewidths of ~0.70 microns
- Contact photolithography to ~2 microns (ALN01, ALN02, ALN03)
- Standard Shipley 1813, 220, 955 positive tone resist processes
- Both positive tone and image reversal processes for AZ5214
- Shipley LOR2A and LOR5A bilayer processes for robust liftoff processes
- Standard SU-8 negative resist processes
Nanotech West has an extensive set of material growth and deposition processes and tools available. They include:
- Metalorganic chemical vapor deposition (MOCVD) of III-V materials, in the form of an Aixtron 3×2″ close-coupled showerhead tool (CVD01) capable of growing (In, Al, Ga) (As, P, Sb) compound semiconductors on substrates up to 100mm
- Electron gun evaporation of a wide variety of standard metals and some dielectrics (EVP01, EVP03)
- RF and DC sputter deposition of a wide variety of metals and some dielectrics using a five-gun AJA Orion RF/DC load-locked sputter tool (PVD03)
- Atomic layer deposition of dielectrics including HfO2, Al2O3, Ta2O5, ZnO, and TiO2 (other films possible with appropriate precursors) using a Picosun R-150B ALE ALD tool (ALD01)
- Two LPCVD silicon nitride processes, stoichiometric and low-stress (TUB02)
- PE-CVD silicon nitride and silicon oxide using a Plasma Therm 790 tool (CVD02)
Nanotech West has extensive capabilities in dry and wet etching. They include:
- Inductively coupled reactive ion etching (ICP-RIE) using a Plasma Therm SLR770 tool (ETC04)
- Plasma etching with a Lam 490 Autoetch (ETC02)
- Reactive ion etching with a Technics Micro-RIE tool (ETC01)
- Low-damage oxygen plasma ashing using a Diener Pico asher (ASH01)
- Wet etching supported by three cleanroom wet benches (HOD07, HOD08, HOD09)
- Spin rinse dryers for 100mm wafer processing
Thermal processing capabilities at Nanotech West include:
- Rapid thermal annealing (RTA01, RTA02)
- Dry and wet silicon oxidations in a shared furnace tube (TUB04)
- Two boron solid-source diffusion processes for silicon (TUB03)
- Two (n- and p-) spin-on dopant processes
- Furnace tube annealing up to 1200° C (TUB06)
- Nitrogen-purged BlueM ovens (OVN01, OVN02)
- HMDS priming oven, YESIII HMDS Vapor Prime (OVN03)
- Low temperature (< 650° C) baking and annealing in
nitrogen and forming gas (TUB01) - Various other ovens and hotplates that support lithography and other processes
The metrology and materials analysis capabilities at Nanotech West include:
- Carl Zeiss Ultra 55 Plus field-emission scanning electron microscope capable of high resolution on conductive and insulating substrates (SEM02)
- Hitachi S-3000 scanning electron microscope (SEM01)
- Extensive optical microscopy and photomicroscopy capabilities
- Electrical probe stations including two light sources for solar simulation
- Woollam alphaSE spectroscopic ellipsometer (ELP03)
- Thin film reflectometry (NMX01)
- Veeco Dektak3 surface profilometry (PRF01)
- Jandel Four-point probe (PRB04)
- Sinton WCT-120 photoconductance lifetime tester (PRB03)
- Bruker Icon 3 Atomic force microscopy (AFM04)
- Energy Dispersive X-Ray Spectroscopy (EDAX on SEM01 EDS01, Oxford EDS SDD on SEM02 EDS02)
- Registration measurements of up to 120mm in both X and Y using electron beam (EBL01) and optical methods
Other significant process capabilities at Nanotech West include:
- Wafer bonding using our EV520HE wafer bonder/hot embossing tool
- Wedge wire bonding using a Kulicke and Soffe 4123 wire bonder – 1.0 mil Au and 1.0 mil Al wire and the corresponding wedges are available
- Manual wafer and sample grinding processes
- An MBraun nitrogen-purged glovebox for handling and processing air-sensitive materials