Submitting InstitutionUniversity of Cambridge
Unit of AssessmentPhysics
Summary Impact TypeTechnological
Research Subject Area(s)
Engineering: Biomedical Engineering, Electrical and Electronic Engineering, Materials Engineering
Summary of the impact
University of Cambridge research led to the creation of spin-out company,
Cavendish Kinetics which developed a micro electro mechanical (MEMS)
process technology that allows MEMS devices to be fabricated in a standard
silicon foundry. The company is now producing RF MEMS technology for
mobile phone applications allowing faster data transfer and lower power
consumption. It initially developed a non-volatile memory product for
harsh environments. The company has provided more than 350 person years of
highly skilled employment (of which 140 person years are within the
period) at offices in the US, UK, the Netherlands, and Korea. It has
developed a large patent portfolio and raised tens of millions of US
dollars in VC funding.
Charles Smith joined the Semiconductor Physics group of the Department of
Physics at the University of Cambridge as an Advanced EPSRC Fellow in 1991
before promotion to Lecturer in 1996. Starting prior to the period, in
1991, Smith (now Professor) began investigations into quantum phenomena in
the electrical mechanical properties of nanometre scale devices. Smith
began investigations into the thermal properties of nanometre scale
devices [r1]. Part of the research involved fabricating free-standing
metal structures less than 0,1 micron wide and thick and a few microns
long. This was some of the first research into the nanomechanical
properties at this length scale and directly led to the initial invention
by Professor Smith of using micro- mechanical devices (MEMS) for
non-volatile memory applications [r2]. This patent was submitted in 1993
and has been cited over 100 times in other patent applications.
Cavendish Kinetics Ltd [i1] was formed in October 1994 by Smith then an
Advanced EPSRC Fellow working on quantum transport phenomena. VC funding
was used by the company to continue research at the University Department
of Physics into the area of the nano-mechanical properties of sub-micron
MEMS devices. This research continued until 2002. The initial
investigations were focussed on studying the lifetime issues related to
fabricating MEMS devices on this length scale. Techniques for reliably
fabricating devices on this length scale, using materials that would be
allowed in a silicon foundry, were also performed during this period
resulting in the following publications [r1, r3, r4]. That research showed
that MEMS devices could be fabricated on this very small length scale, and
that they could be switched millions of times reliably. It also showed
that problems with adhesion at the contacts could be overcome and that the
contact resistance was at a low enough level for real device applications.
That research was basic underpinning research and not development work.
The company paid for this research with grants to the Department of over
References to the research
R1. "Switching Characteristics of Electrostatically Actuated Miniaturized
Micromechanical Metallic Cantilevers."Teh WH, Luo JK, Graham MR, Pavlov A,
Smith CG J.
Vac. Sci. Technol. B (2003) 21 2360, DOI: 10.1116/1.1620515
R2*. Bi-stable memory element. Inventor: SMITH CHARLES GORDON [GB]
Publication info: US5677823; (A), 1997-10-14; Priority Date: 1993-05-08.
R3. Teh WH, Liang CT, Graham M, Smith CG J. Microelectromech. Syst.
(2003) 12 641 "Cross-Linked PMMA as a Low-Dimensional Dielectric
Sacrificial Layer." DOI: 10.1109/JMEMS.2003.817891
R4. Teh WH, Luo JK, Graham MR, Pavlov A, Smith CG
J. Micromech. Microeng. (2003) 13 591 "Near-Zero Curvature Fabrication of
Miniaturized Micromechanical Ni Switches using Electron Beam Cross-Linked
PMMA." DOI: 10.1088/0960- 1317/13/5/309
* References which best represent the quality of the underpinning
Research grant GR/K93013/01): Quantized vibration of micro-mechanical
structures combined with single electron charging, PI: Charles Smith, 25
March 1997 to 24 March 1999, Value: £100,258
Details of the impact
The initial Cambridge research into building MEMS devices on the
nano-scale showed that shrinking MEMS devices allows them to work faster,
at lower voltages and more reliably. The speed of operation enabled these
devices to be used for making small fast operating variable capacitors for
mobile phone applications. The low resistance of the moving metal parts
ensures operation with a high electrical quality factor. The advantage of
using MEMS for memory products is that the low voltage operation removes
the requirement for charge pumps in embedded memory applications.
As mentioned in section 2, the research underpinning the development of
MEMS devices was considered enough to attract a considerable amount of VC
funding. In 2000 the results were such that the company was able to raise
$6,000,000 to hire a CEO and to set up a research lab external to the
University, allowing the company to start developing its first silicon
foundry compatible nano- scale MEMS device, a non-volatile memory product.
This development work was performed outside the department. Pushing for
the smallest possible MEMS devices allowed other products to be developed
with enhanced performance properties such at the digital variable
capacitor that is currently the main product of the company. Joint
research grants between Cavendish Kinetics and the University of Cambridge
Physics Department continued until 2005[i2]. Thereafter, in 2006
$15,500,000 more in VC funding allowed Cavendish Kinetics to set up a
subsidiary in San Jose in California with the CMOS research team shifting
from Germany to the US, allowing the company to grow to over 30 employees.
Within the relevant period, a further $10 million in investments from
Qualcomm and other VC's came into the company (2011) [i4] which allowed
the company to fully develop the digital variable capacitor products for
mobile phone applications.
The latest 4G or LTE technology used in smart phones allows much faster
data transmission because data can be split between more than one band,
both during upload and download. In the UK there are three bands used for
LTE, the value of the frequency used is different for different regions of
the globe. There is no room in the phone to house more than one antenna,
so to solve this problem phones use resonant filters connected to the
antenna to tune them to work at different frequencies. At present this is
achieved with a gallium arsenide switch connected to a fixed capacitor.
This combination is expensive, because the switches need to operate up to
several gigahertz without distorting the signal or damping the resonance.
Ultimately it is predicted that smart phones will need to operate over 20
bands worldwide [i7]. The Cavendish Kinetics solution replaces all these
components with a digital variable capacitor which is fabricated at a
standard CMOS foundry. Cavendish Kinetics ported its unique MEMS process
for nano-scale MEMS devices to a partner foundry TowerJazz Ltd that is
manufacturing chips that will be sold to phone manufacturers. The first
chip was launched in June 2013.
There is another advantage to the Cavendish Kinetics technology and this
relates to the variation in the antenna performance depending on its
position relative to your body. If a phone is sitting on the desk or in
your pocket being used with headphones, the stray capacitance is different
from when it is held in your hand next to your head. This causes a shift
in the performance of the antenna which can be corrected for directly
using Cavendish Kinetics technology in a way that is not possible with the
current technology. Thus this product will allow new phone designs to take
full advantage of new high speed mobile phone networks referred to as LTE
or 4G which are now available in the US, Europe and Japan. It also results
in a longer time between battery charges as less power is required. Being
able to send and receive mobile signals more efficiently means that the
mobile phone signal suppliers do not need to build extra phone mast to
ensure fast data rates are available for everyone. As the chip replaces
several other components, it can also lead to a reduction in the cost of
the parts for the mobile phone.
Thus the research at Cavendish has led to a new product that became
available in 2013 [i3] which reduces the energy consumption and improve
the performance of mobile phones.
On a smaller scale, since 2008 the
development has provided over 140 person years of employment to engineers
and scientists in the US, and Europe and has resulted in over 97 published
Sources to corroborate the impact
i1. Statement from CEO Cavendish Kinetics
2013 launch of new product which reduces the energy consumption and
improve the performance of mobile phones
$10 million in investment from Qualcom
for confirmation of VC backing
for confirmation of investment figures
for details of frequencies required for LTE
i9. "MEMS technology integrated in the CMOS back end" R. Gaddi, R.
Van Kampen, A. Unamuno, V. Joshi, D. Lacey, M. Renault, C. Smith, R.
Knipe, D. Yost. Microelectronics Reliability, 50, (2010),
pp. 1593-1598, DOI: 10.1016/j.microrel.2010.07.113