This epitaxy growth equipment is mainly used for the development of nano and micrometric hetero-structures based on semiconductor elements of columns III-IV-V integrated on silicon substrate for photovoltaic, thermoelectric, microelectronic and photonic applications.
It is compatible with Si substrates of 4 and 8 inches.
It includes:
- An introductory airlock surrounded by a nitrogen glove box
- A chamber UHV for chemical deposition in vapour phase (UHV-CVD) with RHEED in-situ (Reflection High Energy Electron Diffraction) device
- A chamber UHV for chemical beam epitaxy (CBE) with RHEED in-situ
- One XPS/AES (X-Rays Photolélectrons Spectrometry, Auger Electrons Spectrometry) surface characterization chamber
Hydrides (silane, germane, digermane...) or organometallics (tributylarsine, trimethyl gallium, trimethylAluminium, triethylgallium and trimethylindium...) are involved in the two CVD and CBE deposition techniques, which will decompose on the surface of the hot substrate on which growth is desired. The molecules on the surface will break down into subspecies. Hydrogen or Cxhy radicals will evaporate and be evacuated by the pumping system. The III-IV or V elements of the precursor molecule go in turn, and if the deposition conditions are well chosen (temperature and pressure) integrate into the crystal.
The advantages of these techniques are: a good quality of the film deposited, a good homogeneity and reproducibility, a high deposition speed.
The RHEED devices allow to check the state of deoxidation of the substrate after annealing, or to check during growth the crystalline state of the deposited layers.