New Material Technologies in AlGaN/GaN Based Electronic Devices

 We will show a number of new material technologies which can be applied for the AlGaN/GaN electronic devices. These technologies are as follows:

i)                    Application of GaN bulk crystals with dislocation density as low as 10⁴ cm^-2as substrates to construct HEMTs and power devices. Schottky diodes with an ultra low leakage and high breakdown voltage (above 700 V) will be demonstrated.  Fig. 1

shows the I-V characteristics for such diode.

ii)                  Lateral patterning of SiC substrates to modify locally the offcut. This approach has an advantage of paving the way to monolithically integrated GaN-based and SiC-based devices, as they deserve a different substrate off-cut (0.3 and 4 degrees, respectively).

iii)                Lateral patterning of SiC and GaN substrates to get atomically smooth areas, as well as much higher concentration of Al in AlGaN layers avoiding cracking and other defect generation.

For all materials, we will show results of XRD, TEM and AFM studies, as well as electrical characteristics.