Thin Metal Films and Multi-Layers Structure as Absorbers for Infrared Detectors

As thin metal films are known to act as wide-band absorbers for infrared radiation, in this paper Ni metal films are prepared on the Ge surface of double-sided polishing, The results showed the absorbing properties of the metal layer are strongly influenced by the dielectric function of the sensor material. This paper also describes one multi-layers structure as absorber. The structure included a reflector layer of 100-nm-thick Ti (e-beam evaporation), 2-µm-thick polyimide(spin-coating), and 14.9-nm-thick Ni film (e-beam evaporation). These contain a half transmissive thin metal film, a total reflective thin metal film and a quarter-wave polyimide film. The results showed that, measured performance matches well with theoretical predictions.

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Electrical conduction in ultra thin metal films II. Experimental

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1969.0049 ◽

1969 ◽

Vol 309 (1498) ◽

pp. 397-417 ◽

Cited By ~ 35

Keyword(s):

Metal Films ◽

Substrate Material ◽

Thin Metal Film ◽

Thin Metal ◽

Aluminosilicate Glass ◽

Film Material ◽

Thin Metal Films ◽

Bias Effect ◽

Glass Substrates ◽

Barium Aluminosilicate

A number of thin aggregated metal films on glass substrates are analysed in terms of the model proposed earlier (Hill 1969). It is shown that the model is consistent, and that the conductivity of a thin metal film forming an island structure can be defined in terms of the island size and spacing, and of the properties of the substrate and the film material. The potential barrier heights for electron tunnelling between particles of gold, particles of platinum , and particles of silver through soda and barium aluminosilicate glass have been determined. It is shown that the bias effect in thin metal films (Hill 1964 a ) can only be observed with metals of work function close to that of the substrate material and when the substrate contains free alkali ions.

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How Stretchable Can We Make Thin Metal Films?

MRS Proceedings ◽

10.1557/proc-875-o5.5 ◽

2005 ◽

Vol 875 ◽

Cited By ~ 6

Author(s):

Candice Tsay ◽

Stephanie P. Lacour ◽

Sigurd Wagner ◽

Teng Li ◽

Zhigang Suo

Keyword(s):

Metal Film ◽

Metal Films ◽

Rupture Process ◽

Thin Metal ◽

Silicone Elastomer ◽

Thin Metal Films ◽

Electrically Conducting ◽

Au Film ◽

Soft Membrane ◽

Element Simulation

AbstractThin metal films deposited on elastomeric substrates can remain electrically conducting at tensile strains up to ~∼00%. We recently used finite-element simulation to explore the rupture process of a metal film on an elastomer. The simulation predicted the highest stretchability on stiff elastomeric substrates [1]. We now report experiments designed to verify this prediction. A ∼15-μm thick silicone elastomer layer with Young's modulus E ∼ 160 MPa is deposited on a 1mm thick membrane of polydimethylsiloxane (PDMS), a silicone elastomer with E ∼3 MPa. Metal stripes consisting of 25-nm thick gold (Au) film sandwiched between two 5-nm thick chromium (Cr) adhesion layers are fabricated either on top of the stiff layer spun onto the soft membrane substrate, or are encapsulated at the interface between the two elastomers. Encapsulated gold films remain electrically conducting beyond 40% strain. But conductors deposited on top of stiff elastomer lose conduction at strains of 3-8%. These results suggest that, in addition to the stiffness of the elastomeric substrate, the initial microstructure of the metal film plays a role in determining its stretchability.

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Nanostructuration of Thin Metal Films by Pulsed Laser Irradiations: A Review

Nanomaterials ◽

10.3390/nano9081133 ◽

2019 ◽

Vol 9 (8) ◽

pp. 1133 ◽

Cited By ~ 11

Author(s):

Francesco Ruffino ◽

Maria Grazia Grimaldi

Keyword(s):

Metal Film ◽

Metal Films ◽

Research Field ◽

Thin Metal ◽

Metal Nanostructures ◽

Physical Parameters ◽

Pulsed Lasers ◽

Thin Metal Films ◽

Deposited Metal ◽

Reduced Costs

Metal nanostructures are, nowadays, extensively used in applications such as catalysis, electronics, sensing, optoelectronics and others. These applications require the possibility to design and fabricate metal nanostructures directly on functional substrates, with specifically controlled shapes, sizes, structures and reduced costs. A promising route towards the controlled fabrication of surface-supported metal nanostructures is the processing of substrate-deposited thin metal films by fast and ultrafast pulsed lasers. In fact, the processes occurring for laser-irradiated metal films (melting, ablation, deformation) can be exploited and controlled on the nanoscale to produce metal nanostructures with the desired shape, size, and surface order. The present paper aims to overview the results concerning the use of fast and ultrafast laser-based fabrication methodologies to obtain metal nanostructures on surfaces from the processing of deposited metal films. The paper aims to focus on the correlation between the process parameter, physical parameters and the morphological/structural properties of the obtained nanostructures. We begin with a review of the basic concepts on the laser-metal films interaction to clarify the main laser, metal film, and substrate parameters governing the metal film evolution under the laser irradiation. The review then aims to provide a comprehensive schematization of some notable classes of metal nanostructures which can be fabricated and establishes general frameworks connecting the processes parameters to the characteristics of the nanostructures. To simplify the discussion, the laser types under considerations are classified into three classes on the basis of the range of the pulse duration: nanosecond-, picosecond-, femtosecond-pulsed lasers. These lasers induce different structuring mechanisms for an irradiated metal film. By discussing these mechanisms, the basic formation processes of micro- and nano-structures is illustrated and justified. A short discussion on the notable applications for the produced metal nanostructures is carried out so as to outline the strengths of the laser-based fabrication processes. Finally, the review shows the innovative contributions that can be proposed in this research field by illustrating the challenges and perspectives.

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Metal Microstructures in Advanced CMOS Devices

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100164258 ◽

1996 ◽

Vol 54 ◽

pp. 358-359

Author(s):

L. M. Gignac ◽

K. P. Rodbell

Keyword(s):

Grain Boundaries ◽

Semiconductor Device ◽

Chemical Vapor ◽

Microstructural Characterization ◽

Metal Films ◽

Thin Metal ◽

Electrical Performance ◽

Thin Metal Films ◽

Chemical Vapor Deposited ◽

Boundary Properties

As advanced semiconductor device features shrink, grain boundaries and interfaces become increasingly more important to the properties of thin metal films. With film thicknesses decreasing to the range of 10 nm and the corresponding features also decreasing to sub-micrometer sizes, interface and grain boundary properties become dominant. In this regime the details of the surfaces and grain boundaries dictate the interactions between film layers and the subsequent electrical properties. Therefore it is necessary to accurately characterize these materials on the proper length scale in order to first understand and then to improve the device effectiveness. In this talk we will examine the importance of microstructural characterization of thin metal films used in semiconductor devices and show how microstructure can influence the electrical performance. Specifically, we will review Co and Ti silicides for silicon contact and gate conductor applications, Ti/TiN liner films used for adhesion and diffusion barriers in chemical vapor deposited (CVD) tungsten vertical wiring (vias) and Ti/AlCu/Ti-TiN films used as planar interconnect metal lines.

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