Progress in the field of integrated optoelectronics based on porous silicon

S. La Monica, G. Maiello, A. Ferraria, *, G. Masinib, S. Lazarouk, P. Jaguiro and S. Katsouba

a INFM Unità di Roma, Dipartimento di Ingegneria Elettronica, Università di Roma "La Sapienza", Via Eudossiana 18, 00184 Roma, Italy
b Dipartimento di Ingegneria Elettronica, Terza Università degli Studi di Roma, Via della Vasca Navale, 84, 00146 Roma, Italy
c Belarusian State University of Informatics and Radioelectronics, P.Brovki 6, 220027 Minsk, Belarus, Russia

Abstract
Aluminum-porous silicon (Al-PS) Schottky junctions have demonstrated to be promising candidates for stable, wide band emission, silicon based light sources. Aluminum top contacts are defined by transforming the Al layer between different pads into anodic alumina (Al2O3).The light emitted by the devices arises from the border of the metallic contact through the transparent and insulating alumina. With the aim of obtaining a higher external efficiency, different shapes for the aluminum top contact have been designed and characterised. The layout of the masks used in photolithography has been designed having in mind two possible applications for the light source: (1) as a silicon technology-compatible light source to be used for optical interconnections within VLSI-IC, and (2) as a pixel for 1D and 2D electroluminescent panels. An increase of external quantum efficiency due to increase of perimeter/area ratio has been demonstrated. Furthermore, the detection of the light emitted from the junction by means of a porous silicon photodetector integrated on the same chip is presented. Fabricated devices are characterised by means of electrical and optoelectronic techniques.

Author Keywords: Optoelectronics; Porous silicon; Light emission; Photolithography

Index Terms: Integrated optoelectronics; Porous silicon; Semiconductor junctions; Light sources; Light emission; Photolithography; Quantum efficiency; Alumina; Photodetectors; Anodic alumina; Aluminum top contacts