Professional Experience  

02/2013- Present   Assistant Professor, National Center for Nanoscience and Nanotechnology (NCNNUM), University of Mumbai, Vidyanagari, Kalina, Santacruz (E), Vidhyanagari, Mumbai 400 098, India.

2012- 2013, Scientist-D, National Center for Nanoscience and Nanotechnology (NCNNUM), University of Mumbai, Vidyanagari, Kalina, Santacruz (E), Vidhyanagari, Mumbai 400 098, India.

2011-2012, Visiting Scientist, Korean Institute of Science and Technology (KIST), Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791, Republic of Korea

2010-2011, Senior Research Scientist, Department of Electrical Engineering, Indian Institute of Technology (IIT) Powai, Mumbai 400076, India.

 2008-2010, Research Associate, Department of Electronics and Engineering, University of Sheffield, Sheffield, S1 3JD, UK

 2007-2008, Post doctoral fellow, Institut FEMO-ST, Besancon, France.

Awards and recognitions: SERB Technology Translation Award'2020. 

Professional Experience  

08/2019 - present:   Assistant Professor, National Center for Nanoscience and Nanotechnology (NCNNUM), University of Mumbai, Vidyanagari, Kalina, Santacruz (E), Vidhyanagari, Mumbai 400 098, India.

2014 - 2017: Post-doctoral scientist at X-ray Physics Group, Department of Physics, University of Siegen, Germany

2011 - 2014:  Visiting scientist at Raja Ramanna Centre for Advanced Technology, Indore, India

2009 - 2011: Post-doctoral scientist at Solid State Physics Group, Department of Physics, University of Siegen, Germany

Awards and recognitions:  

Professional Experience  

(05/2014 –till date) Assistant Professor, DST-INSPIRE Faculty (2014-2019), National Center for Nanoscience and Nanotechnology, University of Mumbai.

(03/2011 - 03/2014) Visiting Scientist, Nano-functional Powder Research Group, Functional Materials Division, Korea Institute of Material Science.

(04/2010 - 02/2011) Post Doctoral Fellow, Department of Electrical Engineering, IIT Bombay, Powai, Mumbai. (19th April 2010 – 28th February 2011) (Experience at working in class 1000 clean room and Formation of p-ZnO thinfilms by PLD)

Awards and recognitions:

1. DST-INSPIRE Faculty Award 2014 from Department of Science and Technology Government of India.

2. Selected at DESY-Hamburg to conduct experiments on PETRA III X-ray source.

3. Selected as a Foreign Expert at Korea Institute of Material Science on global research laboratory program (2011-2014).

4. Materials Research Society of India Prize for the Best Poster Paper Award for paper entitled “TG-DT analysis for carbon assisted synthesis of C:MgB2” Presented at 19th AGM of MRSI during 14th to 16th February 2008 at  Thiruvananthapuram.

File No. : CRG/2020/001538

Funding Agency: UGC-DAR CRS

Amount of Grant Received : Rs. : 

Status of the Project : Ongoing

Project Summary:

Even today the detection of most of the ionizing radiation is done using gas filled counters which operates at very high voltages. The technique used is expensive, fragile and bulky in nature which has bottle neck its uses at larger scale. In this connection use of high purity Ge have been demonstrated. However the detectors made using Ge operates at liquid nitrogen temperature and are bulky to handle. Considering the complexity associated with these traditional detectors, use of compound semiconductor materials mainly III-nitrides are thought to be advantageous. Apart from other III-nitride material, GaN has received special attention in the optoelectronic industries. The material offers excellent physical as well as chemical properties that mainly include its band gap, large displacement energy, high thermal stability, non-hygroscopic and dense nature as well as high Z value. Due to high Z value, the GaN (and/or allowed with indium) is proposed to be the most suitable material for the detection of ultra-fast and sensitive detection of various ionizing radiations. Researchers have also suggested its use for the detection of neutron and/or gamma radiation in the nuclear reactors where the material always get exposed with the high flux of such radiations. Along with these advantages major benefits to use GaN for fabricating these detectors include the existing fabrication technology, which is already well established for the electronics and optoelectronics that can be integrate to fabricate ionizing radiation detectors. However, commercialization of GaN as a scintillation detectors is not yet realized due to various reasons. Some of the major reasons includes lack of producing high quality materials in thin/thick films and/or nanostructured forms, growth of these materials on suitable low cost competitive substrates which also include flexible substrates, homogeneous doping in GaN to tune the band gap and may more. Understanding these challenges to commercialize GaN as a scintillation material, the proposal intends to study the post effects of various ionizing radiation on the physical and chemical environment of GaN material in various forms (nanostructures, thin, thick films) as a first step before fabricating any such detector which will sustain and work under any harsh environmental conditions.  

File No. : CRG/2020/001538

Funding Agency: SERB-CORE

Amount of Grant Received : Rs. : 28,87,720.00

Status of the Project : Ongoing

Project Summary:

Even today the art of detection of thermal neutrons is gas filled counters, and for gamma radiation detection it is high purity Ge detector. The gas filled detectors are expensive, fragile and bulky as well as they are operated at very high voltages; whereas Ge detectors are bulky as they operate at liquid nitrogen temperatures and cannot operate without liquid nitrogen storage. Compared with these traditional detectors, the detectors made up of compound semiconductor materials mainly III-nitrides are more advantageous. Amongst various III-nitride materials, GaN along with its alloys with aluminum and indium has received special attention towards its use in optoelectronic industries. The unique combination of its physical as well as chemical properties which include band gap, large displacement energy, high thermal stability, high Z value and the density associated with it, GaN can also be utilized as either scintillation material and/or a semiconductor detector for detection of either thermal neutrons or gamma radiations. One of the major benefits to use GaN based materials for detecting towards high energy radiations is its adaptability with the existing technology, which is already well established for the electronics and opto-electronics.  Along with this for ultra-fast, non-hygroscopic, dense and highly sensitive neutron detection usually GaN is heavily doped. The most common dopant elements to create appropriate radiation detection are In, Fe, B and Li, where indium is found to be the most suitable dopant for the detection of neutron and gamma radiations due to its high Z value. Incorporation of indium in to GaN is accepted to be well proven technology. Researchers have proved that such materials may be suitable for the neutron and/or gamma radiation detection, mainly in nuclear reactors where the materials always get exposed with the high flux radiations. However commercialization of GaN detectors mainly for detection of high energy radiations is not yet realized due to many reasons, which include lack of high quality materials, growth on suitable low cost competitive substrates, homogeneous doping for band gap engineering. Understanding these challenges towards the commercialization of GaN material and related technology towards its use in neutron and/or gamma radiation detection, herewith we propose the growth of GaN material using unique deposition system designed and developed i.e. plasma assisted laser ablation technique followed by fabrication and operating demonstration of single pixel GaN (doped with In) detectors having a) sandwich structure b) mesa structure and c) Double-Schottky contact structure respectively. The proposal intends detailed study on effect of radiation damage on fabricated detectors in order to design, demonstrate and deliver the GaN detectors for ionization radiations which will sustain and work under harsh environmental conditions. 

File No. : ECR/2016/000049  

Funding Agency: SERB-TETRA

Amount of Grant Received : Rs. : 30,00,000.00 

Status of the Project : Completed

Innovation: 

Looking at challenges such as user-friendly, low cost, efficient method to growth high quality III-Nitrides in various forms at relatively low temperature; we propose newly designed technique providing following advantages over existing methods 

a. Use of vacuum furnace provides precise and uniform control on temperature of environment inside growth chamber which also has control on the flowing gas rate and required pressure. 

b. Use of short wavelength-high energy laser ablates all type of materials independent of their melting point controlling stoichiometry of doped nanostructures/thin films as a requirements. 

c. Uniform plasma generated inside the vacuum furnace along with the laser ablation provides better control over the stoichiometry. 

d. Control over the phase composition of the materials, eventually at low temperature conditions. 

Combining these parameters together the apparatus designed enables growth of quality III-materials which are very difficult to prepare.

File No. : ECR/2016/000049

Funding Agency: SERB-ECRA

Amount of Grant Received : Rs. : 40,29,874.00 

Status of the Project : Completed 

Project Summary:

The objectives of research proposal is to develop and implement the cost effective and user friendly “Plasma Enhanced Laser Ablation (PELA)” technique for the grow of high quality GaN and its ternary alloyed (Al, In) nanostructures. Knowing problems associated with the quality of crystal and reformed physical-chemical properties mainly observed in catalyst assisted GaN nanostructures, herewith we propose to synthesis high quality GaN nanostructures using PELA route without using any catalyst usually required for growth. To meet the huge market demands and lower down the manufacturing cost we also propose to demonstrate precisely controlled growth of GaN nanostructures (mainly nanorods, nanopyramids) on low cost substrates for e.g. Si using the same technique. Further to increase the “light emitting efficiency”, which is in a demand; herewith we have propose to grow precisely controlled non-polar plane GaN nanostructures. As it is suggested that the internal electric field and bias direction which are orthogonal along the non-polar plane (i.e. (1120)) can cause enhancement in the recombination process may lead to increase the light emitting efficiency. In connection with this homogeneous doping within the alloyed GaN nanostructures synthesized using PELA will be studied in order to understand the band gap engineering. Finally electrical properties and the stability of these structures will be studied by demonstrating the nanodevices (for e.g. field effect transistors, Deep UV detectors, etc.) fabricated on synthesized nanostructures.