ETD

• carrier concentration
• hall measurements
• Indium Arsenide
• metamorphic buffer
• molecular beam epitaxy
• strain
• thickness dependence
• x-ray diffraction

This thesis deals with the growth and characterisation of thin InAs layers on metamorphic buffers grown by Molecular Beam Epitaxy (MBE). The metamorphic buffers consist of a double-slope step-graded InAlAs buffer and a 400 nm thick InAlAs overshoot layer of 84% Indium composition on GaAs (100) substrates. On top of them, a thin InAs layer is deposited. Several samples with different InAs film thickness ranging from 12.5 nm to 500 nm have been grown. High-resolution X-Ray diffraction is used to investigate the structural properties of the samples. In particular, the strain state and crystal quality of the InAs layer has been analysed. Classical Hall Effect measurements are performed in van der Pauw configuration at 300 K and at 3 K, and the evolution of carrier concentration, resistivity, and mobility of the samples as a function of InAs layer thickness is investigated.