Jennifer Gray

 

Assistant Professor, Department of Mechanical Engineering and Materials Science

835 Benedum Hall

412-624-9746, 8069(fax)

jgray@engr.pitt.edu

http://www.engr.pitt.edu/materials/people/facstaff/JenniferGray.html

  

 

Jennifer Gray’s research is in the areas of thin film growth, nanostructure formation, and characterization.  The ability to produce nanostructures at specific locations is important for applications such as quantum computing where quantum dots need to be arranged into logic structures.  One method is combining substrate patterning with self-assembly processes. For example, heteroepitaxial growth of SiGe on Si under kinetically limited conditions, results in the formation of strain-relieving islands only at energetically favorable sites, such as pit edges.  For a pyramidal pit, this results in four islands self-assembled around each pit.  Pit nucleation sites can be created at specific locations by substrate patterning techniques.  The islands sizes are dependent on strain and can therefore be tailored by changing the film composition.

 

 

 

 

 

 

 

 

 

(Top) AFM image is of 20nm Si0.7Ge0.3 film grown on FIB patterned Si substrate.  Islands form around pits nucleated at FIB modified sites.  (Bottom) AFM images show island evolution around a single pit for earlier growth stages.