By Denis Paiste | Materials Processing Center
Ordered patterns of gold nanoparticles on a silicon base can be stimulated to produce collective electron waves known as plasmons that absorb only certain narrow bands of light, making them promising for a wide range of arrays and display technologies in medicine, industry, and science.
Materials Processing Center (MPC)-Center for Materials Science and Engineering (CMSE) Summer Scholar Justin Cheng worked this summer in MIT professor of electrical engineering Karl K. Berggren’s Quantum Nanostructures and Nanofabrication Group to develop specialized techniques for forming these patterns in gold on silicon. “Ideally, we’d want to be able to get arrays of gold nanoparticles to be completely ordered,” says Cheng, a rising senior at Rutgers University.
“My work deals with the fundamentals of how to write a pattern using electron-beam lithography, how to deposit the gold, and how to heat up the substrate so we can get completely regular arrays of particles,” Cheng explains.
In MIT’s NanoStructures Laboratory, Cheng wrote code to produce a pattern that will guide the dewetting of a thin gold film into nanoparticles, examined partially ordered grids with an electron microscope, and worked in a clean room to develop a polymer resist, spin coat the resist onto samples, and plasma clean the samples. He is part of a team that includes graduate student Sarah Goodman and postdoctoral associate Mostafa Bedewy. He was also assisted by the NanoStructures Lab manager James Daley.