Silicon IC Technology
(1) 7400-series TTL technology development (1972-76):
: Mr. P.A. Mhaskar, Mr. T.U. Pisharody, Guidance : Prof. K.V. Ramanathan
MOS (Metal oxide silicon) FET (Field Effect Transistors)
and LSI circuits were taken up as the next level of involvement in the
IC revolution. MOS metal gate technology was developed using a Watch-chip
as the test vehicle. This development was finished in 1979 and first MOS
LSI in India was fabricated in Tata Institute of Fundamental Research labs.
Circuit design was also taken up as an important activity.
Our own graphics layout package, IGSYS, alongwith SPICE (from Berkeley),
MSINC (Stanford), Logsim (HP) were integrated as tools for designing, checking
and laying out MOS LSI circuits. National seminars were held on premises
of Tata Institute of Fundamental Research and our group was recognized
as the leader in the IC technology in India.
A landmark achievement for our group and Tata
Institute of Fundamental Research was reached when we successfully completed
the TTL technology development through the test vehicle of 7420 chip, a
dual quad input NAND gate. The knowhow was then transferred to Bharat Electronics
limited, Bangalore during 1972-73 period. At the same time new computer
programs and plot-cut techniques were developed for designing other TTL
series chips (like 7400 - quad 2-input NAND gate). The 7400 chip was the
first ever chip designed in India, just as 7420 was the first ever TTL
chip fabricated in India.
(2) IC Technology Development at Stanford University (1977-78):
P.W. Barth, Supervisor: Dr. Krishna Saraswat, Guidance : Prof. J.B. Angell)
I worked at the Stanford University as a research
associate at the Stanford IC lab for 1 and 1/2 years. I worked on new IC
technology development (dielectric isolation technology). I designed various
test circuits and a 256-bit static memory as the test vehicle for this
technology. The chip design and fabrication was done successfully in 1978.
A paper was published in IEEE trans. Electron-Devices based on this work.
(3) MOS circuit design and technology development (1978-1980):
(Co-workers: P.S. Subramanian, Dinesh K. Sharma, Guidance : Prof. K.V.
(4) LSI Design course at IIT Madras (1981-82,
1982-83, and 1983-84):
Along with Prof. K.V. Ramanathan, Mr. Dinesh Sharma
and Dr. A.S. Vengurlekar a course on "Introduction to LSI Design" was offered
to B.Tech and M.Tech students during Jul-Dec semesters of 1981-1982.
While others came only for 1 year, I was involved with
the course for all the 3 years (1981-82, 1982-83 and 1983-84). Selected
students came to TIFR during the summer vacation for 3 months to do projects
on LSI design (8 M.Tech. and 2 B.Tech projects). Most of the projects were
LSI designs based on TIFR's own CMOS Gate-Array. One of the chips designed
by a B.Tech. student was realized on silicon through a foundry.
(5) UNIDO (Vienna) Project on "TTL IC Fabrication Facility" (1984-1987):
A project on "TTL IC Fabrication Facility" was awarded
by UNIDO, Vienna to ET&T (a Government of India undertaking) in 1984.
SSE group was involved in the project right from the proposal
stage (1984) to the fabrication of the TTL IC (7400 and 7476) chips in
Mar. to Dec. 1986. The chips had a high yield of 90% on wafer and 65% after
bonding and packaging.
The project was being discussed at very high levels and
contribution by TIFR group, led by me, was recognized as very crucial to
the project by the Chairman, Electronics Commission, (Govt. of India) and
the Chairman & Managing Director of ET&T.
(6) Bipolar IC Technology Transfer to IIT Kharagpur (1988):
The Bipolar IC Technology Know-How Transfer to the Microelectronics
Center, IIT Kharagpur was completed in a phased manner in 1 year's time,
(i) Setting up the laboratory through unit process steps.
(ii) Training of the center's staff in design, fabrication
and testing of bipolar ICs.
(iii) Fabrication of the Transfer Vehicle "TELECHIP"
(iv) Voltage Controlled Oscillator (VCO) chip was designed,
fabricated and tested
Silicon MEMS Technology 1995-2000:
by a group of 3
students in 6 months time.
(7) Silicon MEMS Activity (1995-2000)
This is my current interest. We have setup an Electron-Beam-Lithography
facility and have been using the same for designing masks/patterns for
various MEMS structures and devices. A list of our device activity is given
(i) micro-parts : (1995-97) :
(ii) A MEMS magnetic sensor: (1997-99):
(iii) Current Controlled Curled Tips : (1998-99)
(iv) AutoRanging Torsion Sensors : (1999-2000)
(v) Tunnel-Tips : (1999-2000)
Go to MEMS activity MEMS
work done during 1996-2000
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