0

# Infrared Radiative Properties of Heavily Doped Silicon at Room Temperature

[+] Author and Article Information
S. Basu

George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332

B. J. Lee1

George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332

Z. M. Zhang2

George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332zhuomin.zhang@me.gatech.edu

1

Present address: Department of Mechanical Engineering and Materials Science, University of Pittsburgh, PA 15261.

2

Corresponding author.

J. Heat Transfer 132(2), 023301 (Nov 30, 2009) (8 pages) doi:10.1115/1.4000171 History: Received February 08, 2008; Revised February 20, 2009; Published November 30, 2009; Online November 30, 2009

## Abstract

This paper describes an experimental investigation on the infrared radiative properties of heavily doped Si at room temperature. Lightly doped Si wafers were ion-implanted with either boron or phosphorus atoms, with dosages corresponding to as-implanted peak doping concentrations of $1020$ and $1021 cm−3$; the peak doping concentrations after annealing are $3.1×1019$ and $2.8×1020 cm−3$, respectively. Rapid thermal annealing was performed to activate the implanted dopants. A Fourier-transform infrared spectrometer was employed to measure the transmittance and reflectance of the samples in the wavelength range from $2 μm$ to $20 μm$. Accurate carrier mobility and ionization models were identified after carefully reviewing the available literature, and then incorporated into the Drude model to predict the dielectric function of doped Si. The radiative properties of doped Si samples were calculated by treating the doped region as multilayer thin films of different doping concentrations on a thick lightly doped Si substrate. The measured spectral transmittance and reflectance agree well with the model predictions. The knowledge gained from this study will aid future design and fabrication of doped Si microstructures as wavelength selective emitters and absorbers in the midinfrared region.

<>

## Figures

Figure 1

Comparison of different mobility models for (a) p-type and (b) n-type Si at room temperature with experimental data

Figure 2

Carrier concentration versus doping level calculated from two models for (a) p-type and (b) n-type Si at room temperature. The insets show the degree of ionization.

Figure 3

Comparison of calculated resistivity with measurements from different studies for (a) p-type and (b) n-type Si, for different doping levels at room temperature

Figure 6

Comparison of the doping profiles obtained from SIMS for (a) p-type Si (Sample 2 and 4) and (b) n-type Si (Sample 1 and 3)

Figure 7

Comparison of measured (solid lines) and calculated (dash-dotted lines) transmittance and reflectance (for incidence from either side) of all four samples

Figure 4

Optical constants of p-type silicon for different doping concentrations calculated using the Drude model, including accurate values of carrier mobility and ionization: (a) refractive index, and (b) extinction coefficient. The legends are the same for both figures.

Figure 5

Measured transmittance of (a) p-type and (b) n-type Si annealed at different temperatures. The dashed line with symbols in (b) refers to the transmittance calculated based on the refractive index of Si obtained from Ref. 40 and the extinction coefficient extracted from the measured transmittance at 4 cm−1 resolution. The doping concentration refers to the peak concentration before annealing of the samples.

## Discussions

Some tools below are only available to our subscribers or users with an online account.

### Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections