Real-time thickness control of resonant-tunneling diode growth based on reflection mass spectrometry

We used reflection mass spectrometry (REMS) to control the molecular beam epitaxial growth of resonant-tunneling diode (RTD) structures. The REMS-based thickness value controlled the effusion cell shutter actuation, and compensated in real time for flux transients and short-term flux drift. Use of REMS control during deposition of AlAs, InAs, and InGaAs layers resulted in improved symmetry and reproducibility of the RTD I-V characteristics, compared with time-based, dead-reckoning growth. REMS-based control for flux compensation during growth of GaAs/AlGaAs multi-quantum-well structures is also reported.