Effects of copper interfacial layer on surface characteristics, adhesion and wear durability of fluorocarbon thin film sputtered onto polyimide film substrate

Room temperature liquid metal (LM) showcases a great promise in the fields of flexible functional thin film due to its favorable characteristics of flexibility, inherent conductivity, and printability. Current fabrication strategies of liquid metal film are substrate structure specific and sustain from unanticipated smearing effects. Herein, this paper reported a facile fabrication of liquid metal composite film via sequentially regulating oxidation to change the adhesion characteristics, targeting the ability of electrical connection and electrothermal conversion. The composite film was then made of the electrically resistive layer (oxidizing liquid metal) and the insulating Polyimide film (PI film) substrate, which has the advantages of electrical insulation and ultra-wide temperature working range, and its thickness is only 50 μm. The electrical resistance of composite film can maintain constant for 6 h and could work normally. Additionally, the heating film exhibited excellent thermal switching characteristics that can reach temperature equilibrium within 100 s, and recovery to ambient temperature within 50 s. The maximum working temperature of the as-prepared film is 115 °C, which is consistent with the result of the theoretical calculation, demonstrating a good electrothermal conversion capability. Finally, the heating application under extreme low temperature (−196 °C) was achieved. This conceptual study showed the promising value of the prototype strategy to the specific application areas such as the field of smart homes, flexible electronics, wearable thermal management, and high-performance heating systems.

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Static and Dynamic Response of a Cu-Ni Thin Film Heat Flux Sensor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.960-961.304 ◽

2014 ◽

Vol 960-961 ◽

pp. 304-307

Author(s):

Shuo Wu ◽

Fang Ye ◽

Hang Guo ◽

Chong Fang Ma

Keyword(s):

Thin Film ◽

Heat Flux ◽

Polyimide Film ◽

Heat Flux Sensor ◽

Coating Technology ◽

State Tests ◽

Static And Dynamic Tests ◽

Film Substrate ◽

Different Thickness ◽

Flux Sensor

A Cu-Ni thin film heat flux sensor had been fabricated on a 0.05mm thick polyimide film substrate by vacuum coating technology. The overall dimension of the sensor was 8 mm long and 4 mm wide. A thermopile and a thermocouple were arranged on the substrate to measure both heat flux and surface temperature. The thermopile had 18 thermocouple junctions which formed 9 pairs of differential thermocouples and were covered by two different thickness of thermal resistance layers. This research carried out static and dynamic tests of the thin film heat flux sensor. Seebeck coefficient of thermocouple is 19.3761μV/(°C). Sensitivity of the thermopile is 0.010121μV/(W/m2). Steady-state tests of the thermopile and the thermocouple were taken separately. Time constant of the thermocouple is about 0.26s, which is faster than the thermopile of 1.57s.

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Microtomy of spherical Al2O3 powders

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010007429x ◽

1983 ◽

Vol 41 ◽

pp. 74-75

Author(s):

E.J. Jenkins ◽

D.S. Tucker ◽

J.J. Hren

Keyword(s):

Thin Film ◽

Size Range ◽

Particle Aggregation ◽

Ion Milling ◽

Thin Sections ◽

Α Phase ◽

Convenient Means ◽

Van Der Waals Attraction ◽

Negative Feature ◽

Film Substrate

The size range of mineral and ceramic particles of one to a few microns is awkward to prepare for examination by TEM. Electrons can be transmitted through smaller particles directly and larger particles can be thinned by crushing and dispersion onto a substrate or by embedding in a film followed by ion milling. Attempts at dispersion onto a thin film substrate often result in particle aggregation by van der Waals attraction. In the present work we studied 1-10 μm diameter Al2O3 spheres which were transformed from the amprphous state to the stable α phase.After the appropriate heat treatment, the spherical powders were embedded in as high a density as practicable in a hard EPON, and then microtomed into thin sections. There are several advantages to this method. Obviously, this is a rapid and convenient means to study the microstructure of serial slices. EDS, ELS, and diffraction studies are also considerably more informative. Furthermore, confidence in sampling reliability is considerably enhanced. The major negative feature is some distortion of the microstructure inherent to the microtoming operation; however, this appears to have been surprisingly small. The details of the method and some typical results follow.

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Microstructural investigation of surface roughness in MBE-grown AlAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138646 ◽

1995 ◽

Vol 53 ◽

pp. 454-455

Author(s):

R. Rajesh ◽

R. Droopad ◽

C. H. Kuo ◽

R. W. Carpenter ◽

G. N. Maracas

Keyword(s):

Thin Film ◽

Real Time ◽

Growth Control ◽

Native Oxide ◽

Effusion Cell ◽

Surface Oxide Layer ◽

Microstructural Investigation ◽

Mbe Growth ◽

Film Substrate ◽

And Control

Knowledge of material pseudodielectric functions at MBE growth temperatures is essential for achieving in-situ, real time growth control. This allows us to accurately monitor and control thicknesses of the layers during growth. Undesired effusion cell temperature fluctuations during growth can thus be compensated for in real-time by spectroscopic ellipsometry. The accuracy in determining pseudodielectric functions is increased if one does not require applying a structure model to correct for the presence of an unknown surface layer such as a native oxide. Performing these measurements in an MBE reactor on as-grown material gives us this advantage. Thus, a simple three phase model (vacuum/thin film/substrate) can be used to obtain thin film data without uncertainties arising from a surface oxide layer of unknown composition and temperature dependence.In this study, we obtain the pseudodielectric functions of MBE-grown AlAs from growth temperature (650°C) to room temperature (30°C). The profile of the wavelength-dependent function from the ellipsometry data indicated a rough surface after growth of 0.5 μm of AlAs at a substrate temperature of 600°C, which is typical for MBE-growth of GaAs.

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Investigation of creep stress characterization of thin film/substrate systems with indentation method

Materials at High Temperatures ◽

10.3184/096034007x198094 ◽

2007 ◽

Vol 24 (1) ◽

pp. 67-72 ◽

Cited By ~ 2

Author(s):

BX. Xu ◽

XM. Wang ◽

B. Zhao ◽

ZF. Yue

Keyword(s):

Thin Film ◽

Indentation Method ◽

Creep Stress ◽

Film Substrate

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Interfacial adhesion of nanoporous zeolite thin films

Journal of Materials Research ◽

10.1557/jmr.2006.0060 ◽

2006 ◽

Vol 21 (2) ◽

pp. 505-511 ◽

Cited By ~ 10

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.

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Photoacoustic elastic bending in thin film—Substrate system

Journal of Applied Physics ◽

10.1063/1.4839835 ◽

2013 ◽

Vol 114 (21) ◽

pp. 213510 ◽

Cited By ~ 7

Author(s):

D. M. Todorović ◽

M. D. Rabasović ◽

D. D. Markushev

Keyword(s):

Thin Film ◽

Elastic Bending ◽

Film Substrate

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Exotic Doping for Zno Thin Films: Possibility of Monolithic Optical Integrated Circuit

MRS Proceedings ◽

10.1557/proc-574-317 ◽

1999 ◽

Vol 574 ◽

Cited By ~ 7

Author(s):

Norifumi Fujimura ◽

Tamaki Shimura ◽

Toshifumi Wakano ◽

Atsushi Ashida ◽

Taichiro Ito

Keyword(s):

Thin Film ◽

Thin Films ◽

Nonlinear Optic ◽

Integrated Circuit ◽

Film Surface ◽

Zno Thin Films ◽

Process Window ◽

Electro Optic ◽

Film Substrate ◽

Optical Integrated Circuit

AbstractWe propose the application of ZnO:X (X = Li, Mg, N, In, Al, Mn, Gd, Yb etc.) films for a monolithic Optical Integrated Circuit (OIC). Since ZnO exhibits excellent piezoelectric effect and has also electro-optic and nonlinear optic effects and the thin films are easily obtained, it has been studied as one of the important thin film wave guide materials especially for an acoustooptic device[1]. In terms of electro-optic and nonlinear optic effects, however, LiNbO3 or LiTaO3 is superior to ZnO. The most important issue of thin film waveguide using such ferroelectrics is optical losses at the film/substrate interface and the film surface, because the process window to control the surface morphology is very narrow due to their high deposition temperature. Since ZnO can be grown at extremely low temperature, the roughness at the surface and the interface is expected to be minimized. This is the absolute requirement especially for waveguide using a blue or ultraviolet laser. Recently, lasing at the wavelength of ultraviolet, ferroelectric and antiferromagnetic behaviors of ZnO doped with various exotic elements (exotic doping) have been reported. This paper discusses the OIC application of ZnO thin films doped with exotic elements.

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