UNIST researchers develop process to boost 2D semiconductor performance

Researchers at UNIST have developed a new semiconductor manufacturing process that prevents photoresist residue from contaminating 2D semiconductors, specifically molybdenum disulfide (MoS2). This contamination, caused by plasma exposure during the lithography process, typically creates defects that are difficult to remove without damaging the ultra-thin material.

The team, led by Professors Myung-Soo Kim and Byung-Jo Kim, utilized a 5-nanometer sacrificial gold (Au) film to act as a protective barrier. This layer prevents the photoresist and plasma from directly contacting the MoS2 surface. Once the circuit pattern is formed, the gold film is dissolved using a potassium iodide/iodine (KI/I2) solution, which simultaneously removes any remaining photoresist residue.

This method significantly improves device performance. Transistors produced with this technique showed a tenfold increase in on-current and a reduction in contact resistance to approximately one-tenth of the levels seen in conventional processes. The research indicates that the method is effective across various transistor structures and synthesis methods, potentially accelerating the development of high-density logic and memory devices.