Influence of n-Si Substrate Thickness and Doping Level on the Absorbing Properties of Silicon Plasmon Structures in the Infrared Range

The absorption spectra of Si/SiO2/Si3N4/Si+ and Si/SiO2/Si+ structures with an island surface layer are calculated using the finite difference time domain method. The absorption spectra were modeled depending on the thickness of the substrate and its doping level. It was found that the thickness of the i-Si substrate does not affect the overall absorption of the structure. At the same time, an increase in the thickness of the n-Si substrate leads to an expansion of the absorption band with an intensity of more than 70%. It is established that the doping level of the substrate affects the absorption value of the structures and bandwidth with an absorption value above 80%. It is shown that a wide absorption band with intensity of more than 80% occurs at the doping level of the substrate in the range of 2 . 1019—5 . 1019 cm–3. Dispersion relations in the Si+/SiO2/Si+ structure with an unstructured surface layer are obtained. These dispersion relations may indicate the existence of plasmon oscillations in the system. It is established that a violation of the phase synchronization of the modes at both Si/dielectric interfaces at a significant difference between the doping levels of the substrate and the surface layer can lead to a decrease in the absorption.

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Design and Optimization of a New Micro-Hotplate for Gas Sensor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.791-793.1880 ◽

2013 ◽

Vol 791-793 ◽

pp. 1880-1883

Author(s):

Guo Guang Wang ◽

Xiao Bo Zhang ◽

Chang Bai Liu ◽

Li Liu

Keyword(s):

Gas Sensor ◽

Substrate Thickness ◽

Measuring Electrode ◽

Si Substrate ◽

Element Analysis ◽

Design And Optimization ◽

Sensor Performance ◽

Micro Gas Sensor ◽

The Finite Element Analysis ◽

Electrode Space

This paper reports on the optimization of a novel micro-hotplate with three pins designed for micro-structural gas sensor. The temperature distribution of the Si-substrated micro gas sensor was simulated and analyzed by the finite element analysis (FEA) tool ANSYS. In order to make the gas sensor obtain perfect properties of good temperature uniformity, the thickness of Si substrate, thickness of the front and rear SiO2, measuring electrode width and electrode space were designed to be 150, 50,100, 20 and 500 μm, respectively. The new micro-structural gas sensor is benefit for the improvement of sensor performance.

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Stress Relaxation of a Patterned Microstructure on a Diaphragm

Journal of Materials Research ◽

10.1557/jmr.2002.0266 ◽

2002 ◽

Vol 17 (7) ◽

pp. 1795-1802 ◽

Cited By ~ 1

Author(s):

D. W. Zheng ◽

X. H. Wang ◽

K. Shyu ◽

C. Chen ◽

C-T. Chang ◽

...

Keyword(s):

Thin Film ◽

Residual Stress ◽

Stress Relaxation ◽

Sequential Analysis ◽

Green Laser ◽

Simulation Software ◽

Substrate Thickness ◽

Si Substrate ◽

Written Simulation ◽

Patterned Microstructure

Stress relaxation of a patterned thin film on diaphragms of different material and thickness was investigated through experimental study and numerical simulation. The diaphragm deflections, caused by relaxation of the residual stress in a patterned thin film residing on top, were measured using a Twyman–Green laser interferometer. The first diaphragm used was a Si3N4(top)/SiO2/Si composite diaphragm and the second a 0.5-μm-thick Si3N4 membrane. Custom-written simulation software, which uses a novel numerical algorithm named Nonlinear Sequential Analysis (N-LISA), was utilized to calculate the stress distribution in the patterned thin film and the diaphragm substrate. Agreement between the model and the experimental results was satisfactory. Simulation of the system balance between a tensile-stressed circular Ti film and a stress-free Si substrate of different thickness clearly shows a transition in the substrate behavior from a pure plate to a pure membrane. Interestingly, the deflection of the Si substrate caused by the residual stress in the Ti film reaches its maximum at a certain substrate thickness where plate and membrane characteristics coexist. This study addresses some basic mechanics issues involved in modern devices dealing with thin diaphragms.

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Transmission Electron Microscopy studies of the vacancy ordering in YSI2-X thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087124 ◽

1991 ◽

Vol 49 ◽

pp. 562-563

Author(s):

F.-R. Chen ◽

T. L. Lee ◽

L. J. Chen

Keyword(s):

Crystal Structure ◽

Electron Microscopy ◽

Thin Films ◽

Diffraction Pattern ◽

Annealing Temperature ◽

Lattice Mismatch ◽

Si Substrate ◽

Metal Thin Films ◽

Transmission Electron ◽

Vacancy Ordering

YSi2-x thin films were grown by depositing the yttrium metal thin films on (111)Si substrate followed by a rapid thermal annealing (RTA) at 450 to 1100°C. The x value of the YSi2-x films ranges from 0 to 0.3. The (0001) plane of the YSi2-x films have an ideal zero lattice mismatch relative to (111)Si surface lattice. The YSi2 has the hexagonal AlB2 crystal structure. The orientation relationship with Si was determined from the diffraction pattern shown in figure 1(a) to be and . The diffraction pattern in figure 1(a) was taken from a specimen annealed at 500°C for 15 second. As the annealing temperature was increased to 600°C, superlattice diffraction spots appear at position as seen in figure 1(b) which may be due to vacancy ordering in the YSi2-x films. The ordered vacancies in YSi2-x form a mesh in Si plane suggested by a LEED experiment.

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Electron microscopy studies of PZT ferroelectric film capacitor structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131450 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1364-1365

Author(s):

V. Kaushik ◽

P. Maniar ◽

J. Olowolafe ◽

R. Jones ◽

A. Campbell ◽

...

Keyword(s):

Electric Fields ◽

Sol Gel ◽

Ferroelectric Material ◽

Dielectric Constants ◽

Dielectric Films ◽

Lead Zirconium Titanate ◽

Si Substrate ◽

Film Capacitor ◽

Pzt Films ◽

High Dielectric

Lead zirconium titanate films (Pb (Zr,Ti) O3 or PZT) are being considered for potential application as dielectric films in memory technology due to their high dielectric constants. PZT is a ferroelectric material which shows spontaneous polarizability, reversible under applied electric fields. We report herein some results of TEM studies on thin film capacitor structures containing PZT films with platinum-titanium electrodes.The wafers had a stacked structure consisting of PZT/Pt/Ti/SiO2/Si substrate as shown in Figure 1. Platinum acts as electrode material and titanium is used to overcome the problem of platinum adhesion to the oxide layer. The PZT (0/20/80) films were deposited using a sol-gel method and the structure was annealed at 650°C and 800°C for 30 min in an oxygen ambient. XTEM imaging was done at 200KV with the electron beam parallel to <110> zone axis of silicon.Figure 2 shows the PZT and Pt layers only, since the structure had a tendency to peel off at the Ti-Pt interface during TEM sample preparation.

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A crystallographic analysis of the CoSi/Si(111) interface using Transmission Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176009 ◽

1990 ◽

Vol 48 (4) ◽

pp. 574-575

Author(s):

A.C. Daykin ◽

C.J. Kiely ◽

R.C. Pond ◽

J.L. Batstone

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Defect Structure ◽

Room Temperature ◽

Theoretical Method ◽

Crystallographic Analysis ◽

Si Substrate ◽

Transmission Electron ◽

Theoretical Predictions

When CoSi2 is grown onto a Si(111) surface it can form in two distinct orientations. A-type CoSi2 has the same orientation as the Si substrate and B-type is rotated by 180° degrees about the [111] surface normal.One method of producing epitaxial CoSi2 is to deposit Co at room temperature and anneal to 650°C.If greater than 10Å of Co is deposited then both A and B-type CoSi2 form via a number of intermediate silicides .The literature suggests that the co-existence of A and B-type CoSi2 is in some way linked to these intermediate silicides analogous to the NiSi2/Si(111) system. The phase which forms prior to complete CoSi2 formation is CoSi. This paper is a crystallographic analysis of the CoSi2/Si(l11) bicrystal using a theoretical method developed by Pond. Transmission electron microscopy (TEM) has been used to verify the theoretical predictions and to characterise the defect structure at the interface.

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The reaction of amorphous Ni-Nb films with Si in the presence of a native SiO2 layer

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176459 ◽

1990 ◽

Vol 48 (4) ◽

pp. 664-665

Author(s):

N. Rozhanski ◽

A. Barg

Keyword(s):

High Temperature ◽

Crystallization Temperature ◽

Diffusion Barriers ◽

Sio2 Layer ◽

Si Substrate ◽

Cross Sectional ◽

Plan View ◽

Temperature Range ◽

Sputter Deposited

Amorphous Ni-Nb alloys are of potential interest as diffusion barriers for high temperature metallization for VLSI. In the present work amorphous Ni-Nb films were sputter deposited on Si(100) and their interaction with a substrate was studied in the temperature range (200-700)°C. The crystallization of films was observed on the plan-view specimens heated in-situ in Philips-400ST microscope. Cross-sectional objects were prepared to study the structure of interfaces.The crystallization temperature of Ni5 0 Ni5 0 and Ni8 0 Nb2 0 films was found to be equal to 675°C and 525°C correspondingly. The crystallization of Ni5 0 Ni5 0 films is followed by the formation of Ni6Nb7 and Ni3Nb nucleus. Ni8 0Nb2 0 films crystallise with the formation of Ni and Ni3Nb crystals. No interaction of both films with Si substrate was observed on plan-view specimens up to 700°C, that is due to the barrier action of the native SiO2 layer.

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