RESUMO
Accurate measurement of substrate temperature is one of the most critical process control parameters for molecular beam epitaxy (MBE) growth. Band-edge thermometry instruments have proven to be a valuable tool for process control during MBE growth of semiconductor films, providing as high as ±1 °C temperature resolution. The increasing use of InAs, GaSb, and AlSb iii-v materials necessitates a method for accurately measuring the temperature of their closely lattice-matched GaSb substrates. Current-technology instruments typically rely on InGaAs detector materials which have a maximum wavelength λ detection of â¼1.7 µm, but GaSb substrates have a band gap energy corresponding to λ > 2 µm. A band-edge thermometry instrument capable of λ > 2 µm has been developed using an InAs/InGaSb strained-layer superlattice detector sensitive to 2-9.5 µm long-wave IR wavelengths.