J. Phys. IV France 125 (2005) 447-449  EDP Sciences, Les Ulis DOI: 10.1051/jp4:2005125105 Photocarrier radiometry of ion implanted semiconductors D. Shaughnessy, B. Li, A. Mandelis, J. Batista and J. Tolev Center for Advanced Diffusion-Wave Technologies (CADIFT), Dept. of Mechanical and Industrial Engineering, Univ. of Toronto, 5 King’s College Road, Toronto, Ontario, M5S 3G8, Canada Abstract. The dependence of the photocarrier radiometric (PCR) signal on ion implant dose in Si is reported. The results show almost entirely monotonic behavior over a large range of industrially relevant fluences (1x10 10 to 1x10 16 cm -2 ) for B + , As + , P + , and BF 2 + implanted in Si wafers at various energies. In addition, increasing the absorption coefficient of the excitation source is shown to improve the sensitivity of the PCR amplitude to dose. A three-dimensional three-layer model is used to provide a quantitative understanding of the PCR response of ion-implanted semiconductors. Good agreement between theoretically calculated PCR signal dependence on dose and experimental results is obtained. 1. INTRODUCTION Ion implantation is an important procedure for the selective modification of the electrical properties of near-surface regions of semiconductor materials during microelectronic manufacturing. For industrial purposes the ability to rapidly monitor dose and obtain uniformity maps immediately following the implantation process prior to any further processing with a completely non-contact metrology tool allows related fabrication issues to be identified in the shortest possible time thus maximizing yield. Optical techniques with high sensitivity to the degree of crystalline damage are very suitable to these requirements as evidenced by the emergence of photomodulated reflectance as a popular industrial ion implantation monitoring technology. Photocarrier radiometry [1], a form of modulated room- temperature near-infrared photoluminescence, has recently been developed as a metrological technique for ion implant dose monitoring and was shown to have a monotonic dependence on fluence over a wide range of species, implant dose, and energy, which simplifies dose monitoring [2]. Quantitative modelling of the optoelectronic response of implanted semiconductors is difficult due to the complicated physical structure. Proposed approaches for quantitative models of the photothermal response from an ion implanted semiconductor include numerous two layer models and most recently a multi layer model that scales the optical and electrical properties of each layer to the damage predicted by TRIM calculations [3,4]. A recently developed three layer model [5] that provides a compromise between the simplicity of the two-layer models and the more realistic likeness to the actual physical structure of the implanted material provided by the multi-layer models is used explain the physical nature of the PCR response to implanted semiconductors, specifically Si. 2. THEORETICAL MODEL Photocarrier radiometry is a photonic diagnostic technique that measures the IR emission from a sample excited by an intensity modulated super-bandgap optical source [1]. The harmonic IR emissions due to the generated excess carriers are filtered from any thermal IR (Planck-mediated) Article published by EDP Sciences and available at http://www.edpsciences.org/jp4 or http://dx.doi.org/10.1051/jp4:2005125105