The primary research tool in the Group is a V90S Molecular Beam Epitaxy system, equipped with Si and Ge matrix level sources as well as B and Sb dopants. This MBE tool allows growth conditions to be optimised through independent control of growth rate and substrate tmperature.
The Group also has an industry standard ASM Epsilon 2000E reduced pressure chemical vapour deposition (RP-CVD) tool, capable of producing 100mm, 150mm or 200mm wafers compatible with the highest standards of industrial fabrication facilities.
Many structural probes are available in Warwick including:
- High resolution x-ray diffraction (XRD)
- Secondary ion mass spectrometry (SIMS) - provided by the Analytical Science Projects (ASP) Group
- Cross sectinal and plan view transmission electron microscopy (TEM), including atomic resolution with collaborators
- Atomic force microscopy (AFM)
- Defect reveal etching
- Raman scattering
Device characterisation can be performed on complete wafers or individual devices at temperatures from 0.3K to 400K. Measurement techniques include:
- Input/output device characteristics: threshold voltage, subthreshold slope, transconductance
- Capacitance-Voltage: carrier density, oxide thickness, effective mobility
- Low frequence (1/f) noise
- High frequency characteristics
- Hall bar measurements: carrier density, mobility (including mobility spectrum analysis), analysis of scattering mechanisms
- Magnetotransport: Shubnikov-de Haas oscillation, carrier lifetimes, quantum Hall effects