User login

You are here

thin films

Christian Linder's picture

Understanding geometric instabilities in thin films via a multi-layer model

Dear Colleagues,

I want to share with you our work on geometric instabilities in thin films, which was recently accepted in Soft Matter.

Gi-Dong Sim's picture

High-temperature tensile behavior of freestanding Au thin films

In this paper, the mechanical behavior of freestanding thin sputter-deposited films of Au is studied at temperatures up to 340°C using tensile testing. Films tested at elevated temperatures exhibit a significant decrease in flow stress and stiffness. Furthermore the flow stress decreases with decreasing film thickness, contravening the usual notion that “smaller is stronger”. This behavior is attributed mainly to diffusion-facilitated grain boundary sliding.

This paper has been accepted by Scripta Materialia.

Kamyar M Davoudi's picture

Dislocation Climb in Two-Dimensional Discrete Dislocation Dynamics

In this paper, dislocation climb is incorporated in a two-dimensional discrete dislocation dynamics model. Calculations are carried out for polycrystalline thin films, passivated on one or both surfaces. Climb allows dislocations to escape from dislocation pile-ups and reduces the strain-hardening rate, especially for fully passivated films. Within the framework of this model, climb modifies the dislocation structures that develop during plastic deformation and results in the formation of pile-ups on slip planes that do not contain any dislocation sources.

Gi-Dong Sim's picture

Fatigue of polymer-supported Ag thin films

The fatigue behavior of Ag films on polyethyleneterephthalate substrates was studied using electrical resistance measurements.
Scanning electron microscopy images showed two types of failure: typical fatigue failure with extrusion–intrusion pairs, and ductile
failure with local necking. Once through-thickness cracks are formed in the metal layer, cracks propagate and the resistance increases abruptly for both failure modes. The effect of adhesion on fatigue life is discussed in terms of concurrent delamination, crack initiation and propagation.

Frank W. DelRio's picture

ASME IMECE 2012: Symposium on Tribology of Thin Films and Small-Scale Structures

Dear Colleagues:

We are currently soliciting abstracts for the 2012 ASME IMECE conference on November 9-15, 2012 in Houston, TX.  The symposium is entitled Tribology of Thin Films and Small-Scale Structures and is part of the Mechanics of Solids, Structures and Fluids Track.

 

Yongjie WANG's picture

Finding a PhD position of 2012 Fall about Materials

Being a undergraduate student of Harbin Institute of Technology,China, I will get my bachelor degree in JUL 2012 majoring in Composite Materials and Engineering. Then I want to find an availible PhD position of 2012 FALL to further my study.

I have studied all the basic courses of materials and mechanics in my bachelor education. Also I have got good scores in both class and lab. And you can see details in my CV and PS attached. 

My research interest includes nanoscience, nanotechnology, magnetic materials, thin films, energy materials and mechanical engineering.

Li Han's picture

New methods of analyzing indentation experiments on very thin films

Abstract - Indentation experiments on very thin films are analyzed by employing a rigorous solution to model elastic substrate effects. Two cases are discussed: elastic indentations where film and substrate are anisotropic, and elasto-plastic indentations where significant material pile-up occurs. We demonstrate that the elastic modulus of a thin film can be accurately measured in both cases, even if there is significant elastic mismatch between film and substrate. 

This manuscript has been accepted for publication in Journal of Materials Research.  

Pradeep Sharma's picture

Journal Club Theme of March 2009: Mechanics Issues in Nanocapacitors and Ramifications for Energy Storage

Next generation advances in energy storage for nanoelectronics, micro and nanosensors among others, require capacitors fabricated at the nanoscale. High dielectric constant materials such as ferroelectrics are important candidates for those. Consider the following: the expected capacitance of a 2.7 nm SrTiO3 thin film is 1600 fFmicro-m-2. What is the likely value in reality? 258 fFmicrom-2! This dramatic drop in capacitance is attributed to the so-called "dead layer" effect.

Li Han's picture

Determining the elastic modulus and hardness of an ultra-thin film on a substrate using nanoindentation

Abstract – A data analysis procedure has been developed to estimate the contact area in an elasto-plastic indentation of a thin film bonded to a substrate. The procedure can be used to derive the elastic modulus and hardness of the film from the indentation load, displacement, and contact stiffness data at indentation depths that are a significant fraction of the film thickness. The analysis is based on Yu’s elastic solution for the contact of a rigid conical punch on a layered half-space and uses an approach similar to the Oliver-Pharr method for bulk materials.

Etienne Barthel's picture

Post-Doc position on stresses and adhesion in multilayers (France)

Please note that a post-doc position on stresses and adhesion in optical multilayers is open. The position is for 2-years shared between SVI (Paris) and Phymat (Poitiers).

Link to a virus-free MS Word description of the position:

http://www.saint-gobain-recherche.com/svi/en/image_merethif_position.html

Rui Huang's picture

Thin films: wrinkling vs buckle-delamination

H. Mei, J.Y. Chung, H.-H. Yu, C.M. Stafford, and R. Huang, Buckling modes of elastic thin films on elastic substrates. Applied Physics Letters 90, 151902 (2007).

Two modes of thin film buckling are commonly observed, one with interface delamination (e.g., telephone cord blisters) and the other with no delamination (i.e., wrinkling). Which one would occur for your film?

Andrew Norris's picture

Stephen H. Davis

Pages

Subscribe to RSS - thin films

More comments

Syndicate

Subscribe to Syndicate