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Title: Electronic transport characterization of silicon wafers by spatially resolved steady-state photocarrier radiometric imaging

Abstract

Spatially resolved steady-state photocarrier radiometric (PCR) imaging technique is developed to characterize the electronic transport properties of silicon wafers. Based on a nonlinear PCR theory, simulations are performed to investigate the effects of electronic transport parameters (the carrier lifetime, the carrier diffusion coefficient, and the front surface recombination velocity) on the steady-state PCR intensity profiles. The electronic transport parameters of an n-type silicon wafer are simultaneously determined by fitting the measured steady-state PCR intensity profiles to the three-dimensional nonlinear PCR model. The determined transport parameters are in good agreement with the results obtained by the conventional modulated PCR technique with multiple pump beam radii.

Authors:
 [1];  [2];  [1];  [2]
  1. Institute of Optics and Electronics, Chinese Academy of Sciences, P. O. Box 350, Shuangliu, Chengdu 610209 (China)
  2. (China)
Publication Date:
OSTI Identifier:
22492756
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 118; Journal Issue: 12; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CARRIER LIFETIME; CARRIERS; DIFFUSION; RECOMBINATION; SILICON; SIMULATION; STEADY-STATE CONDITIONS; SURFACES; THREE-DIMENSIONAL LATTICES

Citation Formats

Wang, Qian, University of the Chinese Academy of Sciences, Beijing 100039, Li, Bincheng, E-mail: bcli@ioe.ac.cn, and School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054. Electronic transport characterization of silicon wafers by spatially resolved steady-state photocarrier radiometric imaging. United States: N. p., 2015. Web. doi:10.1063/1.4931773.
Wang, Qian, University of the Chinese Academy of Sciences, Beijing 100039, Li, Bincheng, E-mail: bcli@ioe.ac.cn, & School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054. Electronic transport characterization of silicon wafers by spatially resolved steady-state photocarrier radiometric imaging. United States. doi:10.1063/1.4931773.
Wang, Qian, University of the Chinese Academy of Sciences, Beijing 100039, Li, Bincheng, E-mail: bcli@ioe.ac.cn, and School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054. Mon . "Electronic transport characterization of silicon wafers by spatially resolved steady-state photocarrier radiometric imaging". United States. doi:10.1063/1.4931773.
@article{osti_22492756,
title = {Electronic transport characterization of silicon wafers by spatially resolved steady-state photocarrier radiometric imaging},
author = {Wang, Qian and University of the Chinese Academy of Sciences, Beijing 100039 and Li, Bincheng, E-mail: bcli@ioe.ac.cn and School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054},
abstractNote = {Spatially resolved steady-state photocarrier radiometric (PCR) imaging technique is developed to characterize the electronic transport properties of silicon wafers. Based on a nonlinear PCR theory, simulations are performed to investigate the effects of electronic transport parameters (the carrier lifetime, the carrier diffusion coefficient, and the front surface recombination velocity) on the steady-state PCR intensity profiles. The electronic transport parameters of an n-type silicon wafer are simultaneously determined by fitting the measured steady-state PCR intensity profiles to the three-dimensional nonlinear PCR model. The determined transport parameters are in good agreement with the results obtained by the conventional modulated PCR technique with multiple pump beam radii.},
doi = {10.1063/1.4931773},
journal = {Journal of Applied Physics},
number = 12,
volume = 118,
place = {United States},
year = {Mon Sep 28 00:00:00 EDT 2015},
month = {Mon Sep 28 00:00:00 EDT 2015}
}
  • Industrial n-type Si wafers (resistivity of 5-10 {omega} cm) were H{sup +} ion implanted with energies between 0.75 and 2.00 MeV, and the electronic transport properties of the implanted layer (recombination lifetime, carrier diffusion coefficient, and front-surface and implanted-interface recombination velocities s{sub 1} and s{sub 2}) were studied using photocarrier radiometry (PCR). A quantitative fitting procedure to the diffusing photoexcited free-carrier density wave was introduced using a relatively simple two-layer PCR model in lieu of the more realistic but substantially more complicated three-layer model. The experimental trends in the transport properties of H{sup +}-implanted Si layers extracted from the PCRmore » amplitude and phase data as functions of implantation energy corroborate a physical model of the implanted layer in which (a) overlayer damage due to the light H{sup +} ions decreases with increased depth of implantation at higher energies (b) the implanted region damage close to the interface is largely decoupled from the overlayer crystallinity, and (c) the concentration of implanted H{sup +} ions decreases at higher implantation energies at the interface, thus decreasing the degree of implantation damage at the interface proper.« less
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  • A depth profiling technique using photocarrier radiometry (PCR) is demonstrated and used for the reconstruction of continuously varying electronic transport properties (carrier lifetime and electronic diffusivity) in the interim region between the ion residence layer and the bulk crystalline layer in H{sup +} implanted semiconductor wafers with high implantation energies (∼MeV). This defect-rich region, which is normally assumed to be part of the homogeneous “substrate” in all existing two- and three-layer models, was sliced into many virtual thin layers along the depth direction so that the continuously and monotonically variable electronic properties across its thickness can be considered uniform withinmore » each virtual layer. The depth profile reconstruction of both carrier life time and diffusivity in H{sup +} implanted wafers with several implantation doses (3 × 10{sup 14}, 3 × 10{sup 15}, and 3 × 10{sup 16} cm{sup −2}) and different implantation energies (from 0.75 to 2.0 MeV) is presented. This all-optical PCR method provides a fast non-destructive way of characterizing sub-surface process-induced electronic defect profiles in devices under fabrication at any intermediate stage before final metallization and possibly lead to process correction and optimization well before electrical testing and defect diagnosis becomes possible.« less
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