Researchers discover smarter process to boost device performance

Rochester Institute of Technology researchers have found a more efficient fabricating process to produce semiconductors used in electronic devices. Materials other than silicon can be used successfully in the development process that could increase performance of electronic devices.

This fabrication process—the I-MacEtch, or inverse metal-assisted chemical etching method—can help meet the growing demand for more powerful and reliable nanotechnologies needed for solar cells, smartphones, telecommunications grids and new applications in photonics and quantum computing.

“What is novel about our work is that for the first time we are looking at applying I-MacEtch processing to indium-gallium-phosphide materials. I-MacEtch is an alternative to two conventional approaches and is a technique that has been used in the field—but the materials that have been explored are fairly limited,” said Parsian Mohseni, assistant professor of microsystems engineering in RIT’s Kate Gleason College of Engineering. He is also director of the EINS Laboratory at the university.

Demands for improved computer processing power have led researchers to explore both new processes and other materials beyond silicon to produce electronic components, Mohseni explained. The I-MacEtch process combines the benefits of two traditional methods—wet etching and reactive ion etching, or REI. Indium-gallium-phosphide is one of several materials being tested to complement silicon as a means to improve current capacity of semiconductor processing.

“This is a very well-known material and has applications in the electronics and solar cell industries,” he said. “We are not reinventing the wheel; we are establishing new protocols for treating the existing material that is more cost effective, and a more sustainable process.”

Semiconductor devices are created on wafers through a multi-step process to coat, remove or pattern conductive materials. Traditional processes are wet etch, where a sample with blocked aspects is immersed in an acid bath to remove substances, and reactive ion etching, where ions bombard exposed surfaces on the wafer to change its chemical properties and remove materials in those exposed regions.

Both have been used to develop the intricate electronic patterns on circuits and use silicon as a foundation for this type of patterning. Improving patterning methods by I-MacEtch could mean reducing fabrication complexity of various photonic and electronic devices.