Progress in power electronic devices is currently accepted through the use of wide bandgap materials (WBG). Among them, diamond is the material with the most promising characteristics in terms of breakdown voltage, on-resistance, thermal conductance, or carrier mobility. However, it is also the one with the greatest difficulties in carrying out the device technology as a result of its very high mechanical hardness and smaller size of substrates. As a result, diamond is still not considered a reference material for power electronic devices despite its superior Baliga’s figure of merit with respect to other WBG materials. This review paper will give a brief overview of some scientific and technological aspects related to the current state of the main diamond technology aspects. It will report the recent key issues related to crystal growth, characterization techniques, and, in particular, the importance of surface states aspects, fabrication processes, and device fabrication. Finally, the advantages and disadvantages of diamond devices with respect to other WBG materials are also discussed.

AlN/diamond heterostructures are very promising for high frequency surface acoustic wave (SAW) resonators. In their design, the thickness of the piezoelectric film is one of the key parameters. On the other hand, the film material quality and, hence, the device performance, also depend on that thickness. In this work, polished microcrystalline diamond substrates have been used to deposit AlN films by reactive sputtering, from 150 nm up to 3 m thick. A high degree of the c-axis orientation has been obtained in all cases. SAW one port resonators at high frequency have been fabricated on these films with a proper combination of the film thickness and transducer size

To study the mechanism of zinc diffusion in GaAs, we diffused zinc from a ZnAs₂ source into Si‐doped GaAs samples (n ≊ 1.3 × 10¹⁸ cm⁻³) at different temperatures (from 575 °C up to 700 °C) in sealed evacuated quartz tubes. The samples are characterized by the depth profile of the photoluminescence at different temperatures. The photoluminescence spectra show characteristic emission associated to deep levels of gallium and arsenic vacancies. A detailed analysis of the spectra demonstrates the role played by vacancies in the Zn diffusion process. The spatial correlation between the luminescence spectra and the Zn concentration obtained from secondary ion mass spectroscopy measurements has been demonstrated.

The strain relaxation in linearly graded composition InGaAs layers grown on (001) GaAs substrates by molecular beam epitaxy is studied by transmission electron microscopy (TEM) and double crystal x-ray diffraction (DCXRD). The dislocation distribution in these layers does not coincide with the predicted equilibrium dislocation distribution [J. Tersoff, Appl. Phys. Lett. 62, 693 (1993)]. The dislocation density in the dislocation-rich layer thickness is slightly smaller than the equilibrium density. The thickness of the dislocation-rich region is different in the [110] and [11̄0] directions. A good correspondence exists between the TEM and DCXRD strain measurements. The dislocation distribution observed by TEM has made it possible to design a scheme to grow dislocation-free and unstrained top layers on linearly graded composition buffer layers.