MY RESEARCH ACCOMPLISHMENT
I am working on vertical 3D NAND devices for memory applications at imec.
My doctoral research work at Defence Laboratory, DRDO Jodhpur was on the radiation effect on MOS capacitors of tin oxide (SnO2), hafnium oxide (HfO2) and aluminium oxide (Al2O3) for radiation sensing applications. Thin films and MOS capacitors of SnO2, HfO2 and Al2O3 were deposited by electron beam evaporation method and their gamma and neutron radiation effects were studied. The observed gamma radiation sensitivity through the extracted threshold voltage of MOS capacitor with radiation dose, shows a linear increase and the sensitivity was found to be 1.24 mV/Gy and 0.63 mV/Gy for hafnium oxide and aluminium oxide, respectively. Gamma and neutron radiation effects on tin oxide thin films and MOS capacitors were also explored for sensing applications.
After my PhD, I spent three years as a ‘Post Doctoral Fellow’ in the Centre of Excellence in Nanoelectronics (CEN), IIT Bombay. At CEN, I have had an opportunity to develop Electron Beam Lithography (EBL) and Photolithography for the baseline MOSFET fabrication process, which was a part of Phase-I deliverables of the CEN at IIT Bombay.
Further, we proposed and experimentally demonstrated a high performance epitaxial silicon sub-300 nm punch-through selector diode for cross point memory applications. Epitaxial Si:C process is used to deposit n+/p/n+ layers which were fabricated into 300-nm-diameter vertical punch-through diodes using EBL. High on-current density of > 1 MA/cm2 and high on/off current ratio of > 250 and > 4700 (at opposite polarities) were observed. A switching speed of < 10 ns was measured. On-voltage designability was demonstrated by tuning the p-region doping and length. A WO patent has been granted for this work
After that, I moved to Institute of Semiconductor Engineering at University of Stuttgart, Germany as a group leader, where I have created a research group on ‘Advanced MOS and Bipolar devices’ and worked on (i) Insulated Gate Bipolar Transistors (IGBT) for high power applications: Epitaxial grown vertical IGBT has been demonstrated on thin Si wafer as a test vehicle for the Locally doped channel IGBT and Super Junction IGBT.
(ii) Locally Doped Germanium and Germanium-tin (GeSn) Field Effect Transistor for CMOS applications: A gate all around vertical germanium locally doped channel FET has been demonstrated with varying channel length and local doping concentration. (iii) Interface and transport study of metal/Ge & GeSn Contacts. (iv) Low temperature BEOL compatible Ge based NIPIN and PINIP epitaxial selector .
I am working on vertical 3D NAND devices for memory applications at imec.
My doctoral research work at Defence Laboratory, DRDO Jodhpur was on the radiation effect on MOS capacitors of tin oxide (SnO2), hafnium oxide (HfO2) and aluminium oxide (Al2O3) for radiation sensing applications. Thin films and MOS capacitors of SnO2, HfO2 and Al2O3 were deposited by electron beam evaporation method and their gamma and neutron radiation effects were studied. The observed gamma radiation sensitivity through the extracted threshold voltage of MOS capacitor with radiation dose, shows a linear increase and the sensitivity was found to be 1.24 mV/Gy and 0.63 mV/Gy for hafnium oxide and aluminium oxide, respectively. Gamma and neutron radiation effects on tin oxide thin films and MOS capacitors were also explored for sensing applications.
After my PhD, I spent three years as a ‘Post Doctoral Fellow’ in the Centre of Excellence in Nanoelectronics (CEN), IIT Bombay. At CEN, I have had an opportunity to develop Electron Beam Lithography (EBL) and Photolithography for the baseline MOSFET fabrication process, which was a part of Phase-I deliverables of the CEN at IIT Bombay.
Further, we proposed and experimentally demonstrated a high performance epitaxial silicon sub-300 nm punch-through selector diode for cross point memory applications. Epitaxial Si:C process is used to deposit n+/p/n+ layers which were fabricated into 300-nm-diameter vertical punch-through diodes using EBL. High on-current density of > 1 MA/cm2 and high on/off current ratio of > 250 and > 4700 (at opposite polarities) were observed. A switching speed of < 10 ns was measured. On-voltage designability was demonstrated by tuning the p-region doping and length. A WO patent has been granted for this work
After that, I moved to Institute of Semiconductor Engineering at University of Stuttgart, Germany as a group leader, where I have created a research group on ‘Advanced MOS and Bipolar devices’ and worked on (i) Insulated Gate Bipolar Transistors (IGBT) for high power applications: Epitaxial grown vertical IGBT has been demonstrated on thin Si wafer as a test vehicle for the Locally doped channel IGBT and Super Junction IGBT.
(ii) Locally Doped Germanium and Germanium-tin (GeSn) Field Effect Transistor for CMOS applications: A gate all around vertical germanium locally doped channel FET has been demonstrated with varying channel length and local doping concentration. (iii) Interface and transport study of metal/Ge & GeSn Contacts. (iv) Low temperature BEOL compatible Ge based NIPIN and PINIP epitaxial selector .