Molecular Beam Epitaxy (MBE)

University of Sheffield

There are three MBE growth systems each of which is operated in a state-of-the-art cleanroom facility based in the Nanosciences & Technology complex at the University of Sheffield –  two VG V90 machines and a new dual chamber MBE cluster tool reactor complete with comprehensive in-situ atomic hydrogen cleaning and secondary ion mass spectrometry (SIMS) characterisation capability.

Combined, these three systems allow us to deliver the full range of III-V semiconductor material systems including arsenides, phosphides, antimonides, dilute nitrides and dilute bismide epitaxial structures on 2, 3 and 4” substrates.

MBE reactors

VG Semicon V90-1

  • In operation since 2002
  • As/P/Bi (or dilute N)
  • 12 ports (2x Ga, 2x Al, 2x In, Si, Be, C)
  • Wafer size up to 4”/3 x 2”

Application areas:

  • Lasers/VCSELs
  • Microcavities
  • Telecoms-wavelength quantum dots
  • QCLs

VG Semicon V90-2

  • In operation since 2011 (built in 2003)
  • As/Sb/Bi
  • 10 ports (1x Ga, 1x Al, 2x In, Si, Be, GaTe)
  • Wafer size up to 4”/3 x 2”

Application areas:

  • Mid-IR sources and detectors
  • ICLs, QCLs
  • APDs
  • Type-II Superlattices
  • InSb 2DEGs

DCA Cluster Tool:

  • In operation since 2017
  • Arsenides only
  • Automated sample transfer
  • Hydrogen cleaning and SIMS

Application areas:

  • Quantum well and quantum dot microcavities
  • Waveguide-integrated quantum dot single photon sources
  • Site-controlled quantum dots

University College London

The Facility at UCL expanded from the provision of III-V materials and devices to include group IV epitaxy and hybrid III-V/Group IV epitaxy enabling capabilities in, for example, silicon photonics. They have developed growth techniques to enable a wide range of devices using III-V semi-conductors on silicon, such as InAs Quantum Dot lasers, infrared photodetectors and nanowires all grown directly on silicon substrates.

NEF at UCL has two Veeco GEN-930 MBE reactors, one of which has two chambers connected via UHV transfer system for growth of III-Vs on Si/Ge. The Facility can supply large area Silicon and Silicon/Germanium wafers up to 6″ by arrangement.

UCL Flyer

Veeco GEN 930 Twin Chamber System:

  • The twin chamber system enables growth in group IV (Si ,Ge) and group III-V (GaAs, InP) materials, without exposing the wafer to the laboratory environment.
  • The ability to maintain and transfer wafers under high vacuum from one chamber to the other, ensures the growth surfaces are kept in an ultra-pristine state. Leading to a very low number defects propagating through the growth structure, which in turn results in high quality, high performance devices. 

Veeco GEN 930 III-V MBE System:

High quality III-V materials growth on Si for a range of projects has been developed on this machine, including:

  • III-V quantum dots lasers
  • self-catalysed nanowires on Si
  • high performance InP based uni-travelling carrier photodiodes and
  • GaAs based HEMTs.