Band‐to‐band and free‐carrier absorption coefficients in heavily doped silicon at 4 K and at room temperature

1991 ◽  
Vol 69 (6) ◽  
pp. 3687-3690 ◽  
Author(s):  
S. C. Jain ◽  
A. Nathan ◽  
D. R. Briglio ◽  
D. J. Roulston ◽  
C. R. Selvakumar ◽  
...  
Keyword(s):  
Room Temperature ◽  
Free Carrier ◽  
Free Carrier Absorption ◽  
Absorption Coefficients ◽  
Doped Silicon ◽  
Carrier Absorption ◽  
Heavily Doped

Free carrier absorption in heavily doped silicon layers

2004 ◽  
Vol 84 (13) ◽  
pp. 2265-2267 ◽  
Author(s):  
Joerg Isenberg ◽  
Wilhelm Warta
Keyword(s):  
Free Carrier ◽  
Free Carrier Absorption ◽  
Doped Silicon ◽  
Carrier Absorption ◽  
Heavily Doped

Near-infrared free carrier absorption enhancement of heavily doped silicon in all-dielectric metasurface

2020 ◽  
Vol 117 (13) ◽  
pp. 134101
Author(s):  
Honghao Yu ◽  
Qing Xiong ◽  
Hong Wang ◽  
Ye Zhang ◽  
Yi Wang ◽  
...  
Keyword(s):  
Near Infrared ◽  
Free Carrier ◽  
Absorption Enhancement ◽  
Free Carrier Absorption ◽  
Doped Silicon ◽  
Carrier Absorption ◽  
Heavily Doped ◽  
Dielectric Metasurface

scholarly journals Near-infrared free carrier absorption in heavily doped silicon

2014 ◽  
Vol 116 (6) ◽  
pp. 063106 ◽  
Author(s):  
Simeon C. Baker-Finch ◽  
Keith R. McIntosh ◽  
Di Yan ◽  
Kean Chern Fong ◽  
Teng C. Kho
Keyword(s):  
Near Infrared ◽  
Free Carrier ◽  
Free Carrier Absorption ◽  
Doped Silicon ◽  
Carrier Absorption ◽  
Heavily Doped

Parameterization of Free Carrier Absorption in Highly Doped Silicon for Solar Cells

2013 ◽  
Vol 60 (7) ◽  
pp. 2156-2163 ◽  
Author(s):  
Marc Rudiger ◽  
Johannes Greulich ◽  
Armin Richter ◽  
Martin Hermle
Keyword(s):  
Solar Cells ◽  
Free Carrier ◽  
Free Carrier Absorption ◽  
Doped Silicon ◽  
Carrier Absorption

SIMS Measurements of Oxygen in Heavily-Doped Silicon

1985 ◽  
Vol 59 ◽  
Author(s):  
R. J. Bleiler ◽  
R. S. Hockett ◽  
P. Chu ◽  
E. Strathman
Keyword(s):  
Integrated Circuit ◽  
Secondary Ion Mass Spectrometry ◽  
Signal To Noise Ratio ◽  
Free Carrier Absorption ◽  
Background Signal ◽  
Oxygen Precipitation ◽  
Doped Silicon ◽  
Carrier Absorption ◽  
Heavily Doped ◽  
Secondary Ion

ABSTRACTOxygen precipitation in CZ silicon is known to provide beneficial yield improvements in integrated circuit processing if the location and amount of precipitation can be properly controlled. The concentration of oxygen in the unprocessed silicon substrate is one of the most important variables to control for achieving these improvements. Fourier Transform Infrared Spectroscopy (FTIR) has successfully been used to measure [0] in silicon when the silicon resistivity is greater than about 0.1 Ω-cm. At lower resistivities typical of p+ and n+ substrates used for epi-wafers as free carrier absorption interferes with the FTIR measurement of bulk [0].This work will focus on how to quantitatively measure oxygen in heavily-doped silicon by Secondary Ion Mass Spectrometry (SIMS) with a high sample thruput, low background signal, and tight σ/x distribution. SIMS calibration is performed against FTIR-calibrated substrates with resistivity higher than 0.1Ωcm. Typical background signals as measured in FZ are a factor of 20 below signals in CZ, and the 160− signal in CZ is over 105 count/sec. resulting in an excellent signal-to-noise ratio for each single measurement. Typical thruput is 18 samples per day where each sample is analyzed four to five times to obtain a σ/x of 3% for an oxygen level of 15 ppma (ASTM F121−80).

The conduction bands in 6H and 15R silicon carbide II. Absorption measurements

1967 ◽  
Vol 299 (1458) ◽  
pp. 393-404 ◽  
Keyword(s):  
Relaxation Time ◽  
Effective Mass ◽  
Low Frequency ◽  
Free Carrier ◽  
Frequency Region ◽  
Free Carrier Absorption ◽  
Absorption Coefficients ◽  
High Frequency Region ◽  
Low Frequencies ◽  
Carrier Absorption

It is shown, on the basis of classical theory, that the free carrier absorption in a uniaxial semiconductor having an anisotropic effective mass and relaxation time is characterized by two independent absorption coefficients. For a general multivalley model these absorption coefficients are shown to be quite complicated functions of the effective mass and relaxation time tensors; these functions are considerably simplified if the energy band extrema are located on the symmetry axis. In this case the anisotropy of the effective mass and also that of the relaxation time may be obtained from the free carrier absorption coefficients if these are measured at high frequencies (w 2 >r 2 ≫ 1) and also in the low frequency region (w 2 r 2 ≪ 1) in the same specimen. At low frequencies the free carrier absorption coefficients no longer have a near quadratic dependence upon wavelength but tend to limiting values. Results of measurements in the high frequency region are presented for a number of samples of both the 6H and 15R forms of silicon carbide. At wavelengths for which the absorption is due to free carriers the absorption coefficient for radiation with its electric vector (X) perpendicular to the symmetry axis (c axis) is greater than that for X || c by a factor of ˜ 4 in the 15R polytype and by a factor of ˜ 15 in the 6H form. The wavelength dependences of the absorption coefficients in the high-frequency region are discussed in terms of the probable scattering mechanisms. In one specimen of each polytype the m easurem ents were extended to ˜ 20 μm and the absorption coefficients were observed to approach limiting values as predicted by the theoretical expressions for low frequencies. Quite good agreement was found between the magnitudes of the calculated and observed absorption coefficients, and the onset of low-frequency behaviour was found to occur in approximately the wavelength region predicted by classical theory. From these results the effective m ass in the direction of sym m etry axis was found to be 1.5 ± 0*2 m 0 in the 6H polytype and ˜ 0-53 m 0 in the 15R polytype; the relaxation time appropriate to the axial direction was found to be greater than that for the transverse plane by a factor of 2.5 in the 6H form and 1.6 in the 15R form. Additional absorption bands for X ||c were found at 19.9 μm in 6H SiC and a t 17.5 μm in the 15R polytype and were of magnitude ca . 100 cm -1 and ca . 150 cm -1 respectively; their origin is as yet unknown. All the results reported relate to room temperature.

Sign in / Sign up

Export Citation Format

Share Document