Transcript Special Note (guest lecture) by Dr. V. N. Mani, Scientist-E

CENTRE FOR MATERIALS FOR ELECTRONICS TECHNOLOGY
(Scientific Society, Dept. of Electronics & Information Technology, MCIT, Govt. of India)
IDA PHASE – III, CHERLAPALLY, HCL (PO), HYDERABAD – 500 051
27262437 (O), Fax: +91-40-27261658
www.cmet.gov.in
C-MET Hyderabad laboratory for the last 20 years are engaged in advanced R&D for the
development of indigenous process technology for ultra high purification of gallium and indium
to 7N+ purity level. Purification of 4N+/5N Gallium from both Indian and other raw material
sources was carried out by employing of combination of zone melting, directional freezing and
solidification processes. Relying on and revolving around the Innovative Solidification &
Crystal Growth Concepts, `An indigenous rotational directional solidification system and
novel ultra-purification process method/ technology for 7N+ pure gallium’ was developed
under major DIT/DST/DRDO projects. The purity of 7N+ grade gallium through GD-MS
analysis at NRC, Canada and using 7N+ pure gallium developed by C-MET, GaAs LPE layer(s)
were also grown and the quality of the layer(s) tested at Calcutta University. Limited quantity of
7N+ pure Ga samples was also made available to SSPL, Delhi and IISc. Bangalore for GaAs epigrowth trials under DRDO sponsored C-MET-Calcutta University Joint Project on Gallium.
The major findings and the first time results on purification/ segregation of impurities in Indian
source of Ga were reported and the out come was submitted to DRDO/NRDC for patenting. [1)
Met. Mater. Process. 18 (2006) 107, 2) Jl. Cryst. Growth 311, 1521(2009) and 3) Jl. Appl. Phys.,
104, 1, (2008) with the referee comment - `I congratulate the authors on a nice piece of work’.
The major finding of the projects]
ROLE OF ADVANCED ELECTRONIC AND NANO MATERIALS AND DEVICES
IN STRATEGIC SPACE AND DEFENCE APPLICATIONS
– A BIRD’s EYE VIEW
V. N. Mani
Ultra High Purity Materials Division, Centre for Materials for Electronics Technology,
Department of Electronics & Information Technology, Govt. of India,
Cherlapalli, Hyderabad 500 051, India
e-mail: [email protected]
Ultra high pure (8N+) starting pre-cursor materials are required for advanced emerging GaAs;
Quantum dots based nano-epitaxial electronics and gadgets technology. Gallium ultra-high
purification is a very challenging process technology. Availability of systems required for its
purification, processing and packaging and published results on these areas are seldom available,
No vendor supplies zone-refiner and solidification system specifically required and suitable for
gallium ultra-high purification. Gallium processing systems have to be fabricated indigenously,
criticality tests have to be carried out and lab scale process has to be optimized before taking up
batch scale operations.
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In this overview talk, our decade long efforts in developing ultra high and nano pure (7N)
gallium, indium and their crystals, wafers and the recent nano-scaled systems, which are required
for epitaxial opto and nano- electronics and optoelectronics will be highlighted. The talk will
also cover technological issues namely multi-pass zone-refining, directional solidification and
associated chemical engineering, instrument development aspects, preparation of bulk crystals
and substrates including VLSI principles and practices. The bird’s eye view will be on the
principles and practices pertaining to the crystal and substrate preparation (purity test, in-situ
synthesis of GaAs compound, GaAs crystal preparation, crystal sawing, lapping, edge profiling,
wafer surface etching, inspection & marking, wafer polishing, post polish cleaning, flatness
testing and epitaxy and device fabrication concepts (epitaxy, creation of active regions,
photoresist / oxide formation, patterning, chip etching, doping, chip section development,
source, drain, gate formation (regions), connecting the regions and outer pins, building up
patterned layers and final circuit design aspects. The class clean and green processing scheme(s)
for sample homogenization, preparation, processing analysis and packaging, the usage of the
class clean room (1000), clean benches (100) environment and characterization issues will be
dealt with.
References
1. K. Ghosh, V. N. Mani and S.Dhar Jl. Appl. Phys Vol.13, 133(2009)
2. V. N. Mani et al Materials Science Research India Vol. 6, No.1 (2008)
3. K. Ghosh, V. N. Mani, S.T. Ali and MRP Reddy Metals Materials and Processes 20(2008),
153
4. K. Ghosh, V. N. Mani and S.Dhar Transaction of the Indian Institute of Metals (TIIM) 61
(2008) 1
5. V. N. Mani et al, Metals Materials and Processes Vol.18 (2), 2006, pp 107-118
6. V. N. Mani et al Physics of Semiconductor Devices Vol.1, pp.203-205 (2004) Eds. K.N. Bhat
etal, Narosa Publishers, New Delhi
7. V.N.Mani et al , Physics of Semiconductor Devices Vol.2, pp.1142-1146 (2001) Eds. Vikram
Kumar etal, Allied Publishers, New Delhi
8. V.N.Mani et al.; Jl. Cryst.Growth (Netherlands) 99(1990) 333-340
9 . V.N.Mani et al.; Jl. Appl. Phys.( USA) 69,1399 (1991).
10. V.N.Mani, Bull. Mater. Sci. (India), Vol. 17, pp. 469-478, 1994.
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Dr. V. N. Mani completed his M.Sc, (Physics-Electronics, Presidency College, University of
Madras) in 1985 - and Ph.D. (Crystal Growth- Anna University, Chennai) in 1990. . He has
joined Department of Electronics, Govt. of India, New Delhi in 1991 as Scientist – B. Presently
holding the post of Scientist-E at Centre for Materials for Electronics Technology (C-MET),
Department of Electronics & Information Technology, Govt. of India, Hyderabad. He has more
than 23 years of experience and expertise in the areas of nano pure electronic and energy
materials covering select GaAs, InP, Si, ZnO materials purification, crystal growth processing,
class clean packaging and solar energy systems technology.
He has carried out his postdoctoral research works at LCM, Lyon, France (1996), NRC-Taiwan
(2004) in the select areas of GaAs, InP and ZnO nano epitaxial semiconductor devices and
solar systems development areas.
He has taken–up the following major and critical R&D projects with a view to develop
indigenous process and product technologies relavant to DRDO/ISRO He has/ is directly
involved in the capacities of (Project Leader/Manager/Principal Investigator/ Team Leader) for
projects such as: 1) Gallium refining (3N to 5N purity level), 2) ILTP-Indo-Russian Project on
New Crystals /Materials for Modern Technology Indian Side Project Collaborator- Completed 3)
Gallium Purification (5N to 6N purity level), 4) Automation and Upgradation of Basic Zone
Refiner, 5) Development of nano pure gallium for devices applications, 6) Design &
Development of Controlled Melting and Freezing System for Preparation of Ultra Pure
Materials for Optoelectronics, DST. He and his team has developed the following indigenous
critical systems namely (1) R&D Type Bridgman Crystal Growth System, (2) R&D type Crystal
Puller (3) Gallium Chlorinating System (4) Directional Solidification System (5) Zone-RefinersVertical/Horizontal
He has received and awarded the following major fellowships/awards: a) Young physicist award
(1988), b)Commonwealth research fellowship (1989), c) Postdoctoral fellowship-National
science council, Taiwan d) Overseas research fellowship-CNR Italy & CNRS, France, e) Best
research paper awards (1987, 1990, 2007, 2010), f) UGC/CSIR junior/senior research fellowship
(1986/1988) and Best indigenous process & product technology award( 2010). He has been
selected as Assistant Professor, Delhi College of Engg in 1999 by UPSC.
He has 67 publications, 07 review reports, 04 technology development reports and 02 patents to
his credit. He has attended more than 120 national/international conferences/ workshops /
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schools/ tutorials/ training programs and presented papers/ talks. He has delivered about 63
invited lectures/talks and chaired about 20 technical sessions in international / national
conferences/ workshops/ schools/ tutorials. Also served as a Member, Organizing Committees –
for 13 National and 04 Intl. Conf. Electronic, Photonic, Nano pure Materials, Devices &
Systems, Solar Technology areas. He also served/ serving as in Expert Member-DST/CSIR/
DIT/UGC Projects Reviewer/ Committees and Editorial Board-Materials Research/ Bulletin of
Materials Science/ Nano Technology – Journals. He is a member in 07 scientific
societies/associations. He is a Visiting Professor/ Examiner in PSN Engg. College, Trinelveli,
SRM University, Chennai, GITAM University, Hyderabad & KL University, Vijayawada, VIT
University, Vellore. He has guided 17 Ph.D scholars and 12 M.Tech students.
His and his team’s SIGNIFICANT contribution include :1) Relying and revolving around the
solidification & Bridgman
crystal growth ideas, an indigenous rotational directional
solidification system & ultra- high and nano purification process technology for 7N pure
gallium’ was developed. 2) Successful Maiden Attempt in Developing Indigenous Zone-refining
Systems & Process Technology for Indium Ultra-Purification
and
Related Instrument
Development. These efforts were appreciated by DIT/DST/DRDO/ISRO.
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