Practical Applications of ADESH

adesh.zip:Click HERE to Download a DEMO version of ADESH ADESH works on PC-DOS. You will need the pkunzip.exe utility for this zipped file. ADESH will also work on MAC and UNIX workstations in a DOS window.



Performance of products depends on microscopic structure and properties of materials. Controlling structural defects in materials is an essential part of materials design and quality control effort. We investigate nucleation of defects in materials with a software package "ADESH" (Atomistic DEfect Simulation Handler). The results assist in designing processing strategies to control defect densities in materials.
Case Studies:

• Void Formation in Metal Interconnects
• Formation and Migration of Dislocations Near Trenches Near Devices
• Controlling stresses with alloying
• Formation of Defects in Thin Films
• Crack Nucleation and Growth

Based on above case studies, the need for "Microscopic Monitoring" (e.g. stress measurements, strain distribution, simulations etc.) during production is obvious.

ADESH simulates atomic structures (all fourteen Bravais Lattices) and minimizes energies of defect configurations (vacancies or impurities, dislocations, grain boundaries, stacking faults, hetero-structures, voids, precipitates etc) with various numerical techniques (Static, Monte-Carlo, Simulated Annealing etc.). ADESH is currently used in five countries for:
(a) Design and Development of Materials
(b) "Reverse Engineering": Backtracking Failure of Finished Products.

Other Projects: Examples of ADESH Studies Questions of Previous Months. Discussion of several practical applications of ADESH.
Technical Reports Created or Reproduced using ADESH.



We used ADESH to obtain information about behavior of materials at an atomistic level. Nucleation of defects was directly observed as a result of atom movements. We investigated effect of strain, temperature etc. on defect nucleation. Processing strategies were designed using this information.

For conducting investigations about defects, we used both continuum and atomistic approaches. The continuum approach tended to give singularities in the realm of defects. That is where ADESH proved to be a practical and user friendly software tool to use.

ADESH has applications in academic, research and industrial environments.

List of Previous Projects Using ADESH

• Controlling Dislocation Formation and Migration Near Isolation Trenches During Device Manufacturing
• Suppressing Voids in Metal Interconnects
• Control Crack Formation in Materials
• Evaluate Effect of Substrate Orientation on Film Quality
• Misfit Dislocations in Thin Films
• Effect of Alloying Elements on Dislocation Movements
• Diffusion of Point Defects: Investigate effects of Strain and Other Defects on Diffusion
• Surface Reconstruction

Educational Aid

• Teach Crystallography
• Atomistic Display of Defect Configurations
• Calculate Microscopic Material Properties
• Correlate Experimental Observations with Simulations

Research Aid: Investigative Tool

• Simulate and Analyze Complex Structures such as Superconductors, Hetero-structures etc.
• Provide Corroboration for High Resolution Transmission Electron Micrographs
• Investigate the Effect of Processing Parameters Such as Strain, Temperature, Time, etc. on Defect Nucleation

Questions? Comments? Suggestions?
Send a note to Anjali Nandedkar at CASA Engineering

Anjali Nandedkar, Ph. D.
CASA Engineering
15 Dartantra Drive
Hopewell Junction
NY 12533
U.S.A
Tel.: (845) 226 - 1925

anjali@casaengineering.com
URL: http://www.casaengineering.com/

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