WAVEGUIDING AND 1.54 p m Er 3 + PHOTOLUMINESCENCE PROPERTIES OF ERBIUM DOPED SILICON RICH SILICON OXIDE SE-YOUNG SEO, HAK-SEUNG HAN AND JUNG H. SHIN Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), 373- 1-Kusung-dong, Yusung-gu, Taejon, Korea ABSTRACT The waveguiding and 1.54 ptm Er3+ photoluminescent properties of Er doped silicon-rich silicon oxide (SRSO) are investigated. Erbium-doped SRSO films, which consist of nanocrystalline Si clusters embedded inside Si0 2 matrix, were deposited by electron cyclotron resonance plasma enhanced chemical vapor deposition of SiH 4 and 02 with concurrent sputtering of erbium. The excess Si content of the SRSO films ranged from 0 to 10 at. %, and Er content ranged from 0.01 to 0.3 at. %. After deposition, films were rapid thermal annealed at temperatures between 750 and 1150 °C for durations ranging from 2 to 20 min. to precipitate silicon nanoclusters. All films show strong room temperature 1.54 Vim Er3+ photoluminescence. The luminescence lifetimes that can be > 6 msec. The refractive indices of the SRSO films range from 1.48 to 2.47, increasing with increasing excess Si content. Thus, waveguides can be formed easily by depositing erbium doped SRSO films on 1 jtm thick Si0 2 films. Furthermore, carrier-induced de-excitation mechanisms of excited erbium atoms in SRSO are nearly completely suppressed in such SRSO films, indicating that population inversion of Er 3 ions by carrier-mediated excitation is possible. INTRODUCTION Erbium doping of silicon has received a great deal of attention, since it promises the possibility of developing silicon-based optoelectronics, enabling integration of silicon integrated circuits with photonic devices and circuits [1]. However, erbium doping of bulk silicon has not yielded practical results so far because of a) severe temperature quenching of the luminescence efficiency due to the small bandgap of Si [2] and b) carrier-mediated de-excitation of erbium 4f electrons [3,4]. However, the bandgap of Si can be greatly increased by using Si nanostructures [5]. Therefore, many researchers have investigated the properties of erbium doped Si nanostructures such as porous Si [6,7] and silicon-rich silicon oxide (SRSO), which consists of Si nanoclusters embedded in a Si0 2 matrix [8,9,10]. Furthermore, in such erbium-doped Si nanocrystals, erbium atoms can be excited by transfer of energy from Si nanocrystals with efficiencies that can be several orders of magnitude greater than resonant excitation by direct photon absorption [7,8,9]. In this paper, we report on the effects of preparation conditions on the Er3+ photoluminescent (PL) properties of such erbium-doped SRSO, and demonstrate waveguides using such erbium-doped SRSO. We also show that in SRSO, carrier-mediated de- excitation mechanisms of erbium 4f electrons are greatly suppressed such that population inversion of Er 3 1 ions by carrier-mediated excitation is possible, enabling fabrication of an erbium-doped planar amplifier that does not require a pump laser. EXPERIMENT Er doped SRSO films of varying Si contents were deposited by ECR-PECVD of SiH 4 and 02 with concurrent sputtering of Er and subsequent rapid thermal anneal. Details of the deposition 21 Mat. Res. Soc. Symp. Proc. Vol. 597 © 2000 Materials Research Society