High-Resolution Quadrature Photopyroelectric Spectroscopy of a-Si:H Thin Films Deposited on Silicon Wafers

1995 ◽  
Vol 49 (6) ◽  
pp. 819-824 ◽  
Author(s):  
Jun Shen ◽  
Andreas Mandelis ◽  
Andreas Othonos ◽  
Joseph Vanniasinkam
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Thermal Wave ◽  
Incident Radiation ◽  
Surface Films ◽  
Si Substrates ◽  
Wafer Substrate ◽  
Ir Transmission ◽  
Ft Ir ◽  
Lock In

The recently developed photothermal technique of quadrature photopyroelectric spectroscopy (Q-PPES) has been applied to measurements of amorphous Si thin films deposited on crystalline Si substrates. Direct, meaningful comparisons have been made between purely optical transmission in-phase (IP-PPES) spectra, and purely thermal-wave sub-gap spectra with the use of a novel noncontacting PPES instrument to record lock-in in-phase and quadrature spectra, respectively. FT-IR transmission spectra have also been obtained for a comparison with this IP-PPES optical method. The results of the present work showed that the FT-IR method performs the worst in terms of spectral resolution of thin films and sub-bandgap defect/impurity absorptions inherent in the Si wafer substrate. The optical IP-PPES channel, however, albeit more sensitive than the FT-IR technique, fails to resolve spectra from surface films thinner than 2100 Å, but is sensitive to sub-bandgap absorptions. The thermal-wave Q-PPES channel is capable of resolving thin-film spectra well below 500 Å thick and exhibits strong signal levels from the crystalline Si sub-bandgap absorptions. Depending on the surface thin-film orientation toward, or away from, the direction of the incident radiation, the estimated minimum mean film thickness resolvable spectroscopically by Q-PPES is either 40 Å or 100 Å, respectively.

scholarly journals Experimental Study on the Thickness-Dependent Hardness of SiO2 Thin Films Using Nanoindentation

Coatings ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 23
Author(s):  
Weiguang Zhang ◽  
Jijun Li ◽  
Yongming Xing ◽  
Xiaomeng Nie ◽  
Fengchao Lang ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Grain Size ◽  
Integrated Circuits ◽  
Film Thickness ◽  
Depth Range ◽  
Micro Electro Mechanical Systems ◽  
Si Substrates ◽  
Sio2 Thin Film ◽  
Average Grain Size

SiO2 thin films are widely used in micro-electro-mechanical systems, integrated circuits and optical thin film devices. Tremendous efforts have been devoted to studying the preparation technology and optical properties of SiO2 thin films, but little attention has been paid to their mechanical properties. Herein, the surface morphology of the 500-nm-thick, 1000-nm-thick and 2000-nm-thick SiO2 thin films on the Si substrates was observed by atomic force microscopy. The hardnesses of the three SiO2 thin films with different thicknesses were investigated by nanoindentation technique, and the dependence of the hardness of the SiO2 thin film with its thickness was analyzed. The results showed that the average grain size of SiO2 thin film increased with increasing film thickness. For the three SiO2 thin films with different thicknesses, the same relative penetration depth range of ~0.4–0.5 existed, above which the intrinsic hardness without substrate influence can be determined. The average intrinsic hardness of the SiO2 thin film decreased with the increasing film thickness and average grain size, which showed the similar trend with the Hall-Petch type relationship.

Interfacial adhesion of nanoporous zeolite thin films

2006 ◽  
Vol 21 (2) ◽  
pp. 505-511 ◽  
Author(s):  
Lili Hu ◽  
Junlan Wang ◽  
Zijian Li ◽  
Shuang Li ◽  
Yushan Yan
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Interfacial Adhesion ◽  
Interfacial Strength ◽  
Future Generation ◽  
In Situ Growth ◽  
Seeded Growth ◽  
Si Substrates ◽  
Film Substrate

Nanoporous silica zeolite thin films are promising candidates for future generation low-dielectric constant (low-k) materials. During the integration with metal interconnects, residual stresses resulting from the packaging processes may cause the low-k thin films to fracture or delaminate from the substrates. To achieve high-quality low-k zeolite thin films, it is important to carefully evaluate their adhesion performance. In this paper, a previously reported laser spallation technique is modified to investigate the interfacial adhesion of zeolite thin film-Si substrate interfaces fabricated using three different methods: spin-on, seeded growth, and in situ growth. The experimental results reported here show that seeded growth generates films with the highest measured adhesion strength (801 ± 68 MPa), followed by the in situ growth (324 ± 17 MPa), then by the spin-on (111 ± 29 MPa). The influence of the deposition method on film–substrate adhesion is discussed. This is the first time that the interfacial strength of zeolite thin films-Si substrates has been quantitatively evaluated. This paper is of great significance for the future applications of low-k zeolite thin film materials.

scholarly journals The Effect of Oxygen Mixing Percentage on Structural, Optical and Electrical Properties of ZnTiO3 Thin-films Grown by Rf Magnetron Sputtering.

2021 ◽  
Author(s):  
srinivasa varaprsad H ◽  
sridevi P. V ◽  
Satya Anuradha M ◽  
Srinivas Pattipaka ◽  
pamu D
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Refractive Index ◽  
Magnetron Sputtering ◽  
Thermionic Emission ◽  
Rf Magnetron Sputtering ◽  
Si Substrates ◽  
Atomic Force ◽  
Excitation Coefficient ◽  
Effect Of Oxygen

Abstract Perovskites are important composites in the area of multidisciplinary applications. It is achieved by carefully choosing and tuning the properties of the thin-film at the deposition. In this paper, ZnTiO3 (ZTO) thin-films were being deposited on quartz and N-Si substrates by RF magnetron sputtering. The thin-films were developed at room temperature, oxygen percentage levels varying from 0 to 100, and annealed at 600oC. The electrical, optical, morphological, and structural properties were analyzed as a function of oxygen mixing percentage (OMP). The crystallinity of the cubic structured ZTO thin-film is found to be high at 25 OMP, and it is gradually decreased with increased OMP. The surface morphology of the thin-film is observed, and roughness is measured from the atomic force microscope. Raman Spectroscopy investigated the phase formation and the vibrational modes of the thin-film with their spectral de-convolution. The ZTO thin-films optical properties were investigated using transmittance spectra. The ZTO thin-film indicated the highest refractive index of 2.46, at 633nm with optical bandgap values of 3.57 eV, with a thickness of 145nm and 25 OMP. The refractive index, thin-film thickness, and excitation coefficient were analyzed using the Swanepoel envelope technique. Electrical characteristics of ZTO thin-film are measured from the optimized conditions of the thin-film with conventional thermionic emission (TE) technique.

Deposition and characterization of ZrO2 thin films on silicon substrate by MOCVD

1993 ◽  
Vol 8 (6) ◽  
pp. 1361-1367 ◽  
Author(s):  
Cheol Seong Hwang ◽  
Hyeong Joon Kim
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Substrate Surface ◽  
Relative Dielectric Constant ◽  
Grain Structure ◽  
Breakdown Field ◽  
Electrical Characteristics ◽  
Dielectric Thin Film ◽  
Si Substrates ◽  
Columnar Grain

ZrO2 thin films were deposited at 1 atm on Si substrates by oxidation-assisted thermal decomposition of zirconium-trifluoroacetylacetonate in the temperature range of 300–615 °C. Above a deposition temperature of 400 °C, the deposited thin films have a columnar grain structure, where each grain is perpendicular to the substrate surface with a c-axis preferred crystallographic orientation, and have poor electrical characteristics as a dielectric thin film. But the thin film deposited at 350 °C has a fine equiaxed microcrystalline structure and has superior electrical characteristics of a breakdown field of 1 MV/cm and a relative dielectric constant of 27.

Halochromic optical nose for assessment of spoilage of packed seer fish (II): leaching resistance, correlation between halochromism and volatile amines

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Kesavan Devarayan ◽  
Padmavathi P. ◽  
Kopperundevi Sivakami Nagaraju
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Real Time ◽  
Total Volatile ◽  
Real Time Monitoring ◽  
Content Type ◽  
Color Changes ◽  
Thin Film Sensors ◽  
Ft Ir ◽  
Volatile Amines

Purpose Development of thin film sensors with pH function for noninvasive real-time monitoring of spoilage of packed seafood such as fish, crab and shrimp are described in this study. It is also the purpose of this study to enhance the leaching resistance of the sensors by using a suitable strategy and to quantitatively correlate the sensor’s halochromism with the total volatile amine. Design/methodology/approach To prepare halochromic sensors with better leaching resistance, biocompatible materials such as starch, agar, polyvinyl alcohol and cellulose acetate along with a halochromic dye were used to prepare the thin film sensors. These thin films were evaluated for monitoring the spoilage of packed seafood at room temperature, 4°C and −2°C up to 30 days. The halochromic sensors were characterized using UV-visible and FT-IR spectroscopy. Findings CIELab analyses of the halochromism of the thin film sensors revealed that the color changes exhibited by the sensors in response to the spoilage of seafood are visually distinguishable. Further, the halochromic response of the thin films was directly proportional to the amount of total volatile base nitrogen that evolved from the packed seafood. Excellent leaching resistance was observed for the developed thin film sensors. The halochromic property of the sensors is reversible and thus the sensors are recyclable. Besides, the thin film sensors exhibited significant biodegradability. Originality/value This study provides insights for use of different biocompatible polymers for obtaining enhanced leaching resistance in halochromic sensors. Further, the color changes exhibited by the sensors are in line with the total volatile amines evolved from the packed seafood. These results highlight the importance of the developed halochromic thin film sensors for real-time monitoring of the spoilage of packed seafood.

Investigation on etching selectivity and microstructure of Ag doped Sb2Te thin film for dry lithography

2021 ◽  
Author(s):  
Wei Tao ◽  
Wancheng Shen ◽  
Xingwang Chen ◽  
Lei Chen ◽  
Jing Hu ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Phase Separation ◽  
Raman Spectra ◽  
Laser Exposure ◽  
Si Substrates ◽  
Heat Mode ◽  
Etching Selectivity ◽  
Mixed Gases

Abstract Dry lithography is a promising micro/nanomanufacturing method owing to its advantages of solution-free, absence of undercut and resist swelling. However, heat-mode resist suitable for dry lithography is less reported. This work reported Ag doped Sb2Te thin film as heat-mode resist, and its etching selectivity and microstructures are investigated in detail. It is found that Ag1.44Sb2.19Te thin film possesses high etching selectivity in CHF3/O2 mixed gases and can act as a heat-mode resist. In order to elucidate the mechanism of high etching selectivity, the microstructures of the Ag doped Sb2Te thin films are analyzed according to XRD, Raman spectra, XPS, and TEM methods. Results implies that the etching selectivity is attributed to the phase separation of Ag1.44Sb2.19Te film and formation of Sb phase after laser exposure, leading to the reduction of etching resistance in CHF3/O2 mixed gases. Besides, the pattern transfers from Ag1.44Sb2.19Te to SiO2 and Si substrates are achieved successfully and the etching selectivity of Si or SiO2 to Ag1.44Sb2.19Te are both higher than 2:1. This work may provide a useful guide for the research of dry lithography without wet development.

The Superconducting Energy Gap of Rb3C60 as measured by IR Transmission in Thin Films

1994 ◽  
Vol 359 ◽  
Author(s):  
Daniel Koller ◽  
Michael C. Martin ◽  
Laszlo Mihaly
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Energy Gap ◽  
Bcs Theory ◽  
Infrared Transmission ◽  
Film Resistivity ◽  
Resistivity Measurements ◽  
Superconducting Energy Gap ◽  
Ir Transmission

ABSTRACTThe superconducting energy gap of Rb3C60 has been measured by infrared transmission through a thin film. Resistivity measurements on the same samples in situ indicate a transition to superconductivity at the expected temperature, ∼30K, with distinct gap features appearing in the transmission below this temperature. The results are interpreted in terms of the BCS theory.

Effect of La Dopant on Electrical Properties of Pb(Zr,Ti)O3 Thin Film Capacitors

1999 ◽  
Vol 596 ◽  
Author(s):  
Chang Jung Kim ◽  
Ilsub Chung
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Electrical Properties ◽  
Lead Zirconate Titanate ◽  
Random Access ◽  
Lead Zirconate ◽  
Second Phase ◽  
Pzt Thin Films ◽  
Si Substrates ◽  
Thin Film Capacitors

AbstractLanthanum doped lead zirconate titanate (PZT) thin films have been prepared on Pt/IrO2/Ir/SiO2/Si substrates to improve the ferroelectric and retention properties. The microstructure and electrical properties of the PZT capacitors were evaluated as a function of La content. The crystalline orientation was appreciably influenced by the addition of La in PZT thin films. The microstructures of films containing 0 and 0.5 mol% La were single phase perovskite, but for La = 1 mol%, a second phase was detected by SEM observation. The 0.5 mol% La doped PZT thin film capacitor showed the best ferroelectric and retention properties for ferroelectric random access memory compared to non-doped PZT.

Characterization of Tantalum Nitride Thin Films Deposited on SiO[sub 2]∕Si Substrates Using dc Magnetron Sputtering for Thin Film Resistors

2006 ◽  
Vol 153 (2) ◽  
pp. G164 ◽  
Author(s):  
Nguyen Duy Cuong ◽  
Dong-Jin Kim ◽  
Byoung-Don Kang ◽  
Chang Soo Kim ◽  
Kwang-Min Yu ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Magnetron Sputtering ◽  
Tantalum Nitride ◽  
Dc Magnetron Sputtering ◽  
Si Substrates ◽  
Thin Film Resistors

Enhanced the Dielectric and Tunable Properties of BZNT Thin Films through Adjusting Annealing Process

2012 ◽  
Vol 252 ◽  
pp. 211-215
Author(s):  
Xiao Hua Sun ◽  
Shuang Hou ◽  
Zhi Meng Luo ◽  
Cai Hua Huang ◽  
Zong Zhi Hu
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Dielectric Constant ◽  
Grain Size ◽  
Dielectric Loss ◽  
Annealing Temperature ◽  
Rf Magnetron Sputtering ◽  
Annealing Process ◽  
Si Substrates ◽  
Tunable Properties

Bismuth zinc niobate titanium (Bi1.5Zn0.5 Nb0.5Ti1.5O7) (BZNT) thin films were deposited on PtTiSiO2Si substrates by radio frequency (rf) magnetron sputtering. The microstructure, surface morphology, stress, dielectric and tunable properties of thin films were investigated as a function of initial annealing temperature. It’s found that high initial annealing temperature increases the grain size, dielectric constant and tunability of BZNT films simultaneously and decreases the tensile stress in films. The BZNT thin film annealed from 500 °C to 700 °C shows the highest FOM value of 45.67 with the smallest dielectric loss and upper tunability.

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