Post-Doc – Study of GaN-based complementary transistor architectures H/F

The postdoctoral work will focus on the development of GaN transistors with a p-FET behavior.

There is a strong interest de develop GaN-based logic for high temperatures, radiative environments or for co-integration with power transistors in order to limit parasitics in the gate-drive loop and increase device lifetime.
HEMT-based technologies with a pGaN- or MOS- gate allow to fabricate suitable n-FETs (Field Effect Transistors with an electronic conduction channel) with current densities above 100mA/mm and an Ion/Ioff ration larger than 5 decades. The fabrication of P-FETs (with a conducting channel made-up of holes), does not allow to have as high performance due to the low mobility of holes which is more than one order of magnitude lower than that of electrons as well as the difficulty to obtain ohmic contacts on p-doped GaN with as good of properties as on n-doped GaN.
The work that is proposed here will first consist in revisiting the architectures of the state of the art followed by the proposal of novel structures that allow to potentially obtain improved performance by using TCAD simulations (Synopsys® SentaurusTM). An experimental study of ohmic contacts on p-GaN will be conducted as well, using different metals and epitaxy stacks that could allow to foresee a CMOS compatible device integration.

The work will be lead in collaboration with experts working on device integration, electrical contact technologies on III-V materials, TCAD simulations and epitaxy.