Dr Saptarsi Ghosh

As a device physicist, I like to find solutions that make future devices more energy-efficient and better than the current state-of-the-art, say a brighter LED or a faster transistor. For semiconductors the trick often lies in the materials that go on to make the devices i.e. choosing the right composition for the functional layers, designing how the layers should be stacked, growing them, and finally testing them to make sure that everything went the way planned. For the GaN family, things are further complicated as the unavailability of native substrates forces us to grow these materials on Si or Sapphire generating significant strain and a bunch of defects (such as dislocations) in the epilayers. Understanding and minimizing their ill-effects in device manufacturing and operation is critical for the technology.

Since joining the group in 2018, I have been working on such problems aimed at optimizing GaN-based HEMT transistors and micro-LEDs. To meet the objectives, I grow the materials in the group’s two MOCVD reactors and rely on characterizing techniques such as AFM, HRXRD, PL, Hall-effect, and IV-CV.  Previously, I had briefly worked in Solid State Physical Laboratory India with a research fellowship after completing my doctorate from the Indian Institute of Technology Kharagpur in 2017. My PhD thesis was focused on the MBE growth of GaN HEMTs and investigating the effect of material parameters on device performance and reliability.  Apart from research, I am passionate about teaching and science communication.

A list of my publications can be found here.

Want to know more about me and my reseach or have an interesting idea for collaboration? Just drop me an email.

In early 2024 I have left the Cambridge Center for Gallium nitride for new research adventures as lecturer at the University of Swansea. However, I am still occasionally around and will continue supporting my students in Cambridge.