Expected progress based on aluminium galium nitride Focal Plan Array for near and deep Ultraviolet

¹ Thales Research and Technology, RD 128, 91767 Palaiseau Cedex, France
² GIE, Alcatel-Thales 3-5lab, RD 128, 91767 Palaiseau Cedex, France
³ CNRS-CRHEA, Rue Bernard Gregory, 06560 Valbonne, France

Corresponding author: jean-luc.reverchon@thalesgroup.com

Abstract

The fast development of nitrides has given the opportunity to investigate AlGaN as a material for ultraviolet detection. A camera based on such a material presents an extremely low dark current at room temperature. It can compete with technologies based on photocathodes, MCP intensifiers, back thinned CCD or hybrid CMOS focal plane arrays for low flux measurements. First, we will present results on focal plane array of 320 × 256 pixels with a pitch of 30 μm. The peak responsivity is tuned from 260 nm to 360 nm in different cameras. All these results are obtained in a standard SWIR supply chaine and with AlGaN Schottky diodes grown on sapphire. We will present here the first attempts to transfer the standard design Schottky photodiodes on from sapphire to silicon substrates. We will show the capability to remove the silicon substrate, to etch the window layer in order to extend the band width to lower wavelength and to maintain the AlGaN membrane integrity.