Effects of nanoscale features on infrared radiative properties of heavily doped silicon complex gratings

Based on the prior work by authors, radiative properties of modified complex gratings with nanoscale features are studied. The purpose of this work is to demonstrate, even preliminary, the possibility of using complex gratings and nanoscale surface features to modify far field radiative properties. A finite-difference time-domain numerical scheme was used to model the infrared radiative properties of heavily doped silicon simple and complex gratings. The solutions were validated with those of rigorous coupled-wave analysis method. By properly choosing the carrier concentration and geometry, silicon complex gratings exhibit a broadband absorptance peak resulting from the excitation of surface plasmon polaritons. Meanwhile, the absorptance of four modified complex gratings with attached features has been numerically investigated for the impacts of the attached structures. Firstly, though absorptance spectra of gratings almost remain unchanged, their locations shift towards longer wavelengths. Secondly, the spectral absorptance peak of two modified complex gratings is wider than that of gratings without attached features due to the cavity resonance excitation. Thirdly, the spectral absorptance of complex gratings with square features in three sizes was compared and shows that the peak wavelength shifts toward longer wavelengths with enlarged feature size.

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Infrared Radiative Properties of Heavily Doped Silicon at Room Temperature

Volume 8: Heat Transfer, Fluid Flows, and Thermal Systems, Parts A and B ◽

10.1115/imece2007-41266 ◽

2007 ◽

Cited By ~ 1

Author(s):

S. Basu ◽

B. J. Lee ◽

Z. M. Zhang

Keyword(s):

Carrier Mobility ◽

Room Temperature ◽

Radiative Properties ◽

Multilayer Thin Films ◽

Mems Devices ◽

Si Substrate ◽

Model Predictions ◽

Doped Silicon ◽

Infrared Spectrometer ◽

Heavily Doped

This paper describes an experimental investigation on the infrared radiative properties of heavily-doped silicon (Si) at room temperature. Lightly-doped Si wafers were ion implanted with boron and phosphorus atoms to doping concentrations of 1×1020 and 1×1021 cm−3. Rapid thermal annealing was performed to activate the implanted dopants. A Fourier-transform infrared spectrometer was employed to measure the normal transmittance as well as reflectance of the samples in the spectral region from 2 to 20 μm. Accurate carrier mobility and ionization models were identified after carefully reviewing the available literature, and then incorporated into 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 Si substrate. The measured spectral transmittance and reflectance agree well with the model predictions. The results obtained from this study will facilitate the future applications of heavily-doped Si in semiconductor as well as MEMS devices.

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Impact of arsenic and phosphorus concentration on oxygen content in heavily doped silicon single crystal

Journal of Crystal Growth ◽

10.1016/j.jcrysgro.2020.125820 ◽

2020 ◽

Vol 548 ◽

pp. 125820

Author(s):

Roberto Scala ◽

Maria Porrini ◽

Vladimir Voronkov

Keyword(s):

Single Crystal ◽

Oxygen Content ◽

Silicon Single Crystal ◽

Phosphorus Concentration ◽

Doped Silicon ◽

Heavily Doped ◽

Impact Of Arsenic

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Temperature Characteristics of a Contour Mode MEMS AlN Piezoelectric Ring Resonator on SOI Substrate

Micromachines ◽

10.3390/mi12020143 ◽

2021 ◽

Vol 12 (2) ◽

pp. 143

Author(s):

Sitao Fei ◽

Hao Ren

Keyword(s):

Quality Factor ◽

Bottom Electrode ◽

Temperature Stability ◽

Cryogenic Cooling ◽

Silicon On Insulator ◽

Temperature Hysteresis ◽

Sensing Applications ◽

Doped Silicon ◽

Heavily Doped ◽

Contour Mode

As a result of their IC compatibility, high acoustic velocity, and high thermal conductivity, aluminum nitride (AlN) resonators have been studied extensively over the past two decades, and widely implemented for radio frequency (RF) and sensing applications. However, the temperature coefficient of frequency (TCF) of AlN is −25 ppm/°C, which is high and limits its RF and sensing application. In contrast, the TCF of heavily doped silicon is significantly lower than the TCF of AlN. As a result, this study uses an AlN contour mode ring type resonator with heavily doped silicon as its bottom electrode in order to reduce the TCF of an AlN resonator. A simple microfabrication process based on Silicon-on-Insulator (SOI) is presented. A thickness ratio of 20:1 was chosen for the silicon bottom electrode to the AlN layer in order to make the TCF of the resonator mainly dependent upon heavily doped silicon. A cryogenic cooling test down to 77 K and heating test up to 400 K showed that the resonant frequency of the AlN resonator changed linearly with temperature change; the TCF was shown to be −9.1 ppm/°C. The temperature hysteresis characteristic of the resonator was also measured, and the AlN resonator showed excellent temperature stability. The quality factor versus temperature characteristic was also studied between 77 K and 400 K. It was found that lower temperature resulted in a higher quality factor, and the quality factor increased by 56.43%, from 1291.4 at 300 K to 2020.2 at 77 K.

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