The Outstanding Research Award was established to encourage research breakthroughs and the pursuit of academic excellence.
Dr. Po-Wen Chiu’s research has been focused on graphene (Gr) and 2D layered semiconductors, covering fundamental material growth, transport properties, and device applications. The most pressing challenge in the development of advanced electronics based on 2D layered semiconductors stems from the lack of site-selective synthesis of complementary n- and p-channels with low contact resistance. Dr. Chiu’s research has been dedicated to solving this problem. A series of studies related to the 2D-contact issue have been reported by his group. One of the most important figures of merit is an in-plane epitaxial route for the growth of interlaced 2D semiconductor monolayers using chemical vapor deposition with a gas-confined scheme, in which patterned Gr serves as a guiding template for site-selective growth of Gr-WS2-Gr and Gr-WSe2-Gr heterostructures. The Gr/2D semiconductor interface exhibits a transparent contact with a nearly ideal pinning factor for both the n-channel WS2 and the p-channel WSe2. The effective Fermi level depinning provides an ultralow contact resistance. Thus, integrated logic circuits made of 2D layered semiconductors have become possible. An inverter, a NAND gate, static random-access memory, and a five-stage ring oscillator were constructed using the complementary Gr-WS2-Gr-WSe2-Gr heterojunctions as a fundamental building block. These devices exhibited the prominent performance metrics of high operation frequency, low power consumption, large noise margins, and high operational stability.