MODELING OF P-N JUNCTION OF III GROUP NITRIDE BY FINITE DIFFERENCE METHOD

Kristupas Razas1, Tomas Grinys1

1 Institute of Photonics and Nanotechnology, Vilnius University

[email protected]

This work aims at detailed examination and modeling of p-n junction of III group nitrides.

We analyzed experimental IV curves of planar structure prepared by metal original chemical vapor deposition (MOCVD) equipment. The equivalent scheme consisting of a diode, and two resistances connected in parallel and series way was applied to fit the IV curves.

It was assumed the current in p-n junction diode is due to two components: space-charge region(scr) recombination/generation and quasi-neutral region (qnr) recombination/generation.

The modeling of p-n junction was performed by finite difference method. The equations of Poisson's, current-density, continuity including equations describing radiative and nonradiative recombination of charge carriers were applied in the model. The band diagram, carrier density and IV curve was extracted from model.

We compared the theoretical IV curve to the experimental one. The received data will be useful for the further optimization of device structure.

Figure 1
Fig. 1. Experimental IV curves. Arrows show the direction of increase resistance in low current and high current range respectively.