Er-DOPED POROUS SILICON LED FOR INTEGRATED OPTOELECTRONICS L. Tsybeskov, G. F. Grom, K. D. Hirschman, H. A. Lopez, S. Chan and P. M. Fauchet Department of Electrical Engineering, University of Rochester, Rochester, NY; V. P. Bondarenko Belarusian State University of Informatics and Radioelectronics, Minsk, Belarus. ABSTRACT Porous silicon (PSi) was doped by Er using electromigration from a solution and converted to Er-doped silicon-rich silicon oxide (SRSO:Er) by partial thermal oxidation at 600- 950°C following densification at 1 100°C in an inert atmosphere. Room-temperature photoluminescence (PL) at -1.5 gtm is intense and decreases by less than 20% from 12 K to 300 K. The PL spectrum of SRSO:Er reveals no luminescence bands related to Si-bandedge- recombination, point defects or dislocations, and shows that the Er3+ centers are the most efficient radiative recombination centers. A light-emitting diode (LED) with an active layer made of SRSO:Er was manufactured using a pre-oxidation cleaning step to increase the quality of the interface between SRSO:Er and the top electrode. Room temperature electroluminescence at -1.5 gim was demonstrated. INTRODUCTION The realization of practical optoelectronic integrated circuits could lead to important applications such as chip-to-chip interconnects, parallel processing and the integration of photonics on silicon chips. Erbium-doped silicon (Si:Er) has been the subject of extensive investigations since the 1980s when low-temperature luminescence at 1.5 Rim was reported [1]. Recently, room-temperature luminescence from Si-based materials doped by Er has been demonstrated in: c-Si co-implanted by oxygen (Si:O:Er) [2]; semi-insulating polycrystalline Si (SIPOS) [3]; amorphous Si (a-Si) [4]; and porous Si (PSi), prepared by electrochemical etching of c-Si. In the case of PSi, erbium has been incorporated through ion implantation [5] or electroplating [6]. It has been suggested that the recombination of spatially confined electron-hole pairs in Si-nanograins, which is responsible for the visible luminescence in PSi [7, 8], promotes efficient energy transfer and excitation of Er ions incorporated in Si nanoclusters [5,6]. The alternative model suggests that the Er'÷ luminescence is mediated by photocarriers in the amorphous Si:O:H or Si:O-matrix produced by a thermal oxidation of PSi [9]. Recently, photo-(PL) and electroluminescence (EL) has been reported in partially oxidized PSi, but no evidence of the charge transfer mechanism related to Si nanocrystals has been found [10]. The purpose of this work is to study light-emitting properties of Er+ doped Si-rich silicon oxide SRSO(Er) and to develop a prototype of a SRSO(Er)-based light-emitting device (LED). EXPERIMENTAL PROCEDURE In this work the samples were produced by anodic etching of boron-doped c-Si wafers with a resistivity p = 1 - 0.05 Q cm in an HF-ethanol solution (1:1) under a current density J = 2-20 mA/cm2. The thickness of the PSi layers varies from 0.5 to 5 gim with porosities from 145 Mat. Res. Soc. Symp. Proc. Vol. 486 © 1998 Materials Research Society