IEEE SENSORS JOURNAL, VOL. 10, NO. 5, MAY 2010 997

Silicon on Insulator Diode Temperature Sensor–A Detailed Analysis for Ultra-High

Temperature OperationSumita Santra, Prasanta K. Guha, Syed Zeeshan Ali, Ibraheem Haneef, and Florin Udrea

Abstract—Silicon diodes can be used for accurate temperaturemonitoring up to higher temperatures in a variety of sensorssuch as micro-machined resistive and calorimetric gas sensors,thermal flow sensors, exhausts, etc. This paper investigates theperformance of a diode temperature sensor when operated atultra high temperatures (up to 780 C). A low leakage silicon oninsulator (SOI) diode was designed and fabricated in a 1.0 �

CMOS (complementary metal oxide semiconductor) process. Thediodes were suspended within a dielectric membrane [formed bypost CMOS deep reactive ion etching (DRIE)] for efficient thermalinsulation. A CMOS compatible micro-heater was integrated withthe diode on the dielectric membrane for local heating. It wasfound that the diode forward voltage exhibited a linear dependenceon temperature as long as the reverse saturation current remainedbelow the forward driving current. We show experimentally thatthe maximum temperature up to which the linearity of diode’sforward voltage output is maintained can be as high as 550 C.Long term continuous operation at high temperatures (400 Cand 500 C) showed good stability of the diode voltage drop.Finally, we present a detailed theoretical analysis that helps todetermine the maximum operating temperature for the diode andalso explains the presence of nonlinearity factors in diode voltageoutput at ultra high temperatures.

Index Terms—Diode temperature sensors, high-temperaturesensors, smart sensors, SOI CMOS.

I. INTRODUCTION

T HE temperature sensor is one of the main building blocksin modern integrated circuits (ICs). On chip temperature

sensors are essential for thermal management of power hungrycircuits which tend to operate close to the maximum junctiontemperature. For bulk silicon complementary metal oxidesemiconductor (CMOS), the maximum operable temperatureis 125 C or 150 C; this can be extended up to 200 C by

Manuscript received September 07, 2009; revised November 11, 2009; ac-cepted November 16, 2009. Current version published March 31, 2010. This isan expanded paper from the IEEE SENSORS 2008 Conference and was pub-lished in its proceedings. The associate editor coordinating the review of thispaper and approving it for publication was Prof. Ergeny Katz.

S. Santra, S. Z. Ali, and F. Udrea are with the Department of Engi-neering, University of Cambridge, Cambridge CB3 0FA, U.K. (e-mail:ss778@cam.ac.uk; sza20@cam.ac.uk; fu10000@cam.ac.uk).

P. K. Guha is with the Department of Engineering, University of Cambridge,Cambridge CB3 0FA, U.K. and also with the School of Engineering, Universityof Warwick, Coventry CV4 7AL, U.K. (e-mail: pkg23@cam.ac.uk).

I. Haneef is with the Department of Engineering, University of Cambridge,Cambridge CB3 0FA, U.K. and also with the Institute of Avionics and Aeronau-tics, Air University, Islamabad 44000, Pakistan (e-mail: ih238@cam.ac.uk).

Color versions of one or more of the figures in this paper are available onlineat http://ieeexplore.ieee.org.

Digital Object Identifier 10.1109/JSEN.2009.2037822

using silicon on insulator (SOI) technology. Hence, there ishardly any need to have on-chip temperature sensors capableof monitoring ICs temperatures beyond this level.

However, some IR (Infra Red) sources or detectors and evenmore prominently some of the new generation of smart sensorsoperate at temperatures well beyond 200 C. One example is themicro-machined calorimetric and resistive gas sensors, whichneed very high temperature (300–500 C) operation for effec-tive reaction with toxic gases [1]–[5]. Temperature monitoringof these devices is necessary to achieve better sensitivity and se-lectivity in presence of different gases. The SOI based diode isan attractive choice for a temperature sensor because it is com-pact in size, gives linear response up to ultra-high temperatures( C) [6] and is simpler to integrate with on-chip, sensordrive and readout circuitry.

While SOI diode temperature sensors have been utilized forlow to medium level temperature monitoring in different appli-cations (e.g., invasive blood velocity measurements [7], temper-ature rise in SOI devices [8], wall shear stress measurements[9], bonding stress sensing in 3-D chips [10]), there are onlyfew reports that investigate or analyze the performance of SOIdiodes based temperature sensors to temperatures up to or be-yond 250 C [11]–[13]. One of these [11], describes a workfunction type SOI diode temperature sensor and compares itsperformance with that of a diode on bulk silicon substrate. Thebulk silicon diode exhibited a maximum operable temperatureof 150 C only after which the reverse bias leakage current in-creased drastically, rendering it unusable beyond that tempera-ture. In the other study [12], a smart SOI CMOS temperaturesensor has been described that uses a SOI lateral PIN diode fortemperature sensing up to 250 C. The only study that reportsresults on SOI diode based temperature sensors beyond 250 Cis by Kimura and Toshima [13], in which p-n junction diodeshave been characterized for their performance from 200 C to500 C. The diode was forward voltage biased for temperatures

C to 150 C and reverse voltage biased for temperatures150 C to 500 C. The temperature measurement in the reversecurrent mode is very difficult because the leakage current is verysmall (under 10 at room temperature) and varies verysignificantly from wafer to wafer and lot to lot. These SOI p-njunction diode temperature sensors, fabricated on a micro-air-bridge, were used for humidity and vacuum sensing applica-tions [14], [15]. There are few reports on high temperature per-formance and/ or analysis of bulk silicon based diode temper-ature sensors as well [16]–[18], but none of these reports dealswith the temperature sensing characteristics of silicon diodes

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998 IEEE SENSORS JOURNAL, VOL. 10, NO. 5, MAY 2010

beyond 377 C. For instance, Ang [16] investigated the elec-trical characteristics of epitaxial high-low junction n+-n-p+ sil-icon diodes in the temperature range 27 C to 310 C; in [17],Boltovets et al. reported on forward voltage characteristics ofa silicon diode temperature sensor from 0–600 K ( C to327 C ), while Shwarts et al. [18] explored silicon diode tem-perature sensors’ characteristics to a maximum temperature of650 K (377 C).

We have recently reported for the first time initial experi-mental results on the performance of an SOI CMOS diode tem-perature sensor operated at ultra-high temperatures up to 780 C[6], [19], [20] . Here we extend our preliminary data with a fullset of experimental results (which include some reproducibilitydata from different wafers) and give a more detailed descrip-tion of the design features and operating principles. Additionalmethods of determining the maximum operating temperature ofthe diode sensor are developed and matched with experimentaldata.

The paper continues with the detail behavior of the SOI diodetemperature sensor when operated well beyond its normal oper-ating temperature. Both analytic modeling as well as softwarebased numerical simulations have been carried out to analyzethe behavior of the SOI diode temperature sensor (both in thelinear and nonlinear regions). By using different methods, wehave also calculated the maximum operating temperature upto which diode characteristics remain linear. The experimentaldata matches very well with the analytical model and simula-tion results. The long term continuous operation at 400 C and500 C for 100 h showed that the SOI temperature diodes arevery reliable.

II. DESIGN AND FABRICATION

The micro-hotplate consists of a resistive heater and a diodetemperature sensor, both embedded within a thin dielectricmembrane (ca. 5 ). The membrane has a circular shape toreduce its edge mechanical stress (as there are no sharp cor-ners). The membrane is made of three layers: 1) at the bottom,the buried oxide—this is a high quality grown oxide which actsas an etch-stop during the deep reactive ion etching (DRIE)fabrication of the membrane; 2) the inter-dielectric layers(ILDs) made of low-temperature deposited silicon dioxideand a plasma enhanced chemical vapor deposition (PECVD)silicon nitride used also in the CMOS process as a passivationand moisture barrier. The membrane has a 300 diameterto reduce the power consumption of the micro-heater. Themicro-heater with 24 diameter is located in the center ofthe membrane. It has a multiringed shape designed for goodtemperature uniformity. The diode, built in the silicon islandbelow the tungsten micro-heater, is made of p+/p-/n+ layers,and has a diameter of 30 . A 1.0 SOI process with threemetal layers using tungsten as an interconnect metal was usedto form the heater and the diode in the CMOS foundry. Thediodes were formed within the thin SOI layer, while the heaterwas formed using the first metal layer. Tungsten is used as ahigh temperature interconnect metal in some CMOS processes,and is particularly advantageous for use as a heater as it hasa very high melting point, and is much less susceptible toelectromigration when compared to aluminum.

Fig. 1. Fabricated micro-hotplate with embedded SOI diode temperaturesensor.

The SOI CMOS process was followed by a back side deepreactive ion etch step to form the membrane at a commercialMEMS foundry, using the buried oxide as an etch-stop. The pic-ture of a fabricated device taken from an optical microscope isshown in Fig. 1. As can be seen, the membrane aligns perfectlywith the top metal alignment marks, ensuring a high yield andhighly reproducible electro-thermal characteristics. The tung-sten heater was used for heating the diode locally for its perfor-mance evaluation up to 780 C. This structure was used as partof a nano-materials based resistive gas-sensor and its responseto gases at relatively low temperatures ( C) has been re-ported elsewhere [21].

III. SOI DIODE MEASUREMENT AND CHARACTERIZATION

It is well known that the silicon diode forward voltage de-creases linearly with an increase in temperature when driven bya constant current. The driving current needs to be low enoughto avoid any self heating while simultaneously providing a highratio with respect to the reverse saturation (i.e., leakage) cur-rent. Keeping both these competing requirements in view. Themaximum drive current was selected as 100 for the measure-ments. This would result in a dc parasitic diode power consump-tion of 27 which translates to an extra self-heating temper-ature of 1 C at 500 C. This is assumed to be negligible whencompared to other error factors, such as those arising from cal-ibration, the temperature uniformity across the heater, the par-asitic series resistances of the diode, etc. At the same time theratio between the drive current and leakage current at room tem-perature was 2.94 allowing an extended linear range forthe voltage temperature function to 600 C. The forward voltageacross the diode was measured at different temperatures up to780 C. The micro-heater embedded in the membrane was usedas a heat source. It was first calibrated with a high precisioncomputer control hot chuck with 1 C resolution.

The forward voltage versus temperature ( - ) plot is givenin Fig. 2. The slope was found to be C (with100 driving current). To check the effects of driving currenton diode performance, three different currents 100 nA, 10 ,and 100 were used. It was found that the - slope and

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SANTRA et al.: SILICON ON INSULATOR DIODE TEMPERATURE SENSOR 999

Fig. 2. Forward voltage drop versus temperature plot of Si diode driven with aforward of 100 ��.

Fig. 3. IR measurements of the microhotplate at 250 C. Note that the tem-perature profile is more accurate in the heater area as beyond this the dielectricmembrane.

the maximum operating temperature for the diode depends sig-nificantly on the driving current and the diode output becomesnonlinear at high temperatures ( C when driven with100 current).

To ensure that the diode performance is not affected due toany temperature gradients within the diode itself, the tempera-ture distribution over the membrane area was also studied withan infrared (IR) camera (Quantum Focus Instruments Infras-cope II). The maximum allowed temperature for IR measure-ments using QFI Infrascope was only 250 C. The IR measure-ment results confirm that temperature is relatively uniform overthe heater area (within 15 C) while it decreases rapidly beyondthat, across the rest of the membrane as shown in Fig. 3. We cantherefore assume that there are very little temperature gradientswithin the SOI diode.

To verify the repeatability of the diode performance, theexperimental characterization of the SOI diodes was first car-ried out on several dies across one wafer and then from waferto wafer on two different fabrication lots. It was found thatin spite of diode’s operation at a very high temperature, theresults are still very reproducible (as shown in Fig. 4). This wasencouraging and demonstrated a reliable temperature sensorperformance.

The SOI diode stability was also rigorously studied in long-term continuous operation 400 C and 500 C. A continuousrun for 100 h demonstrates its long-term stability (the drift inthe diode voltage drop when supplied with a constant current).The maximum deviation was found to be 7 C and 40 C, re-spectively, at those temperatures (as shown in Fig. 5). This was

Fig. 4. Forward voltage versus temperature characterization of the SOI diodeson several devices across one wafer and from wafer to wafer.

Fig. 5. Performance of the SOI diode during 100 h of continuous operation at400 C and 500 C .

Fig. 6. Temperature distribution ( at two temperatures, 275 C and 770 C)over the membrane area by ANSYS simulation. Note that the temperature ismore uniform over the heater area and the devices remain close to room tem-perature after the membrane rim.

slightly unexpected. When analyzed more deeply, it was re-vealed that this change was not predominantly due to a changein diode characteristics, but due to a change in the electrical re-sistance of the tungsten micro-heater [19]. Accounting for thischange in the temperature, the actual drift in the diode outputvoltage was found to be only C.

IV. SIMULATION AND THEORETICAL INVESTIGATION

Extensive simulations (in ANSYS and ISE TCAD) were car-ried out to understand and evaluate the experimental results. TheANSYS simulation shows that the temperature distribution overthe heater area is almost uniform [shown in Fig. 6 at two tem-peratures (275 C and 770 C)] which is consistent with the IR

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1000 IEEE SENSORS JOURNAL, VOL. 10, NO. 5, MAY 2010

measurements. The ISE TCAD was used to simulate (taking intoaccount doping concentrations) the - plot of our device.

The standard diode equation for p-n diode is

(1)

where is saturation current, is voltage drop across thediode, is the Boltzmann’s constant. The saturation current isexpressed by the following equation:

(2)

where is a constant that includes the density of states, theeffective masses of electrons and holes, carrier mobility, dopingdensity, recombination life time, junction area, etc., is aprocess dependent parameter ( ), is the extrapolatedbandgap voltage at 0 (1.14 V for Si) , is the intrinsiccarrier concentration in the semiconducting material. has avery strong dependence on temperature given by the followingformula:

(3)

From (1), the voltage across the diode is

(4)

Using (4) and (2) the voltage can be expressed

(5)

To develop the equation for , (5) is re-written for two tem-peratures, namely an arbitrary temperature and a specified ref-erence temperature (keeping the current constant) [22]

(6)

Therefore, the voltage across the diode is the sum of a con-stant term (first term), a term proportional to the absolute tem-perature (second term) and two nonlinear terms. Neglecting thetwo nonlinear terms the temperature gradient can be expressedas

(7)

At 300 , , at 100 ,the temperature gradient of the diode can be calculated as

Fig. 7. Experimental, theoretical and simulated � -� plot for the SOI diodewhen operated with 100 ��, 10 �� and 100 nA driving current. There is rea-sonably good agreement between experimental data, finite element simulations,and analytical calculations.

Fig. 8. Effect of the nonlinear term [last term of (6)] on the total voltage dropof the SOI diode as a function of the operating temperature.

, which is the same as that determined from theexperimental results. The simulated (in ISE TCAD), theoretical[calculated from (6)] and experimental plot also show excellentmatching with each other (shown in Fig. 7).

The first nonlinear term in (6) increases with the tempera-ture. However, this nonlinear effect can be removed by usingtwo driving currents with a known ratio for the same diode or byusing the same current to drive two different diodes having dif-ferent areas that have a known ratio. Nevertheless, it is very diffi-cult to compensate the last nonlinearity term of (6). In Fig. 8, wehave plotted the last nonlinear term at 100 . It was found thatthe contribution of this term is negligible at low temperature.This is because the last term contains the saturation current. Thesaturation current is proportional to the square of the intrinsiccarrier concentration which has at its term an exponential tem-perature dependence. At low temperature, the intrinsic carrierconcentration is very small (i.e., 9.5 at 27 C) whencompared to the majority carrier concentration (i.e., doping con-centration 5 ). This is to say that the diode is ex-trinsic. As the temperature increases the intrinsic carrier con-centration increases exponentially. As a result, at high temper-ature the diode is no longer extrinsic and the intrinsic conduc-tion is the dominating mechanism during forward-bias. Thus,

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SANTRA et al.: SILICON ON INSULATOR DIODE TEMPERATURE SENSOR 1001

the diode’s nonlinear behavior becomes prominent at high tem-peratures (above 550 C). The reason for this linear operationup to 600 C is due to the use of a very thin active silicon layer(i.e., SOI layer) with a very low volume of the depletion region.This results in a very low value of the reverse saturation current(i.e., leakage during reverse bias), at room tem-perature. Since the increase in nonlinearity is directly causedby an increase in the saturation current (i.e., leakage current)at high temperatures [from (2) and (3)] which in turn is dueto the rapid increase in the intrinsic carrier concentration (asmentioned in the previous paragraph), then having a very smallleakage current level to start with is the key to preserve the lin-earity of the diode at very high temperatures (e.g., 500 C). Theintrinsic carrier concentration increases exponentially with tem-perature (e.g., at 27 C is 9.5 and at 650 C is1.49 ). At high temperatures, the saturation currentbecomes comparable to the drive current and could even exceedthe drive current. As a consequence of this, the last term dom-inates over the other terms of (6) resulting in the - plot be-coming severely nonlinear as shown in Fig. 8. It was also foundthat the high-temperature nonlinearity occurs at lower temper-atures for lower driving currents. This is expected as the satu-ration current becomes dominant over the driving current at alower temperature level.

V. MAXIMUM LINEAR TEMPERATURE OPERATION

From the discussion above, one can define the maximum op-erating temperature as the threshold temperature for the on-setof voltage-temperature nonlinearity. Here, we present threedifferent methods of calculating the maximum temperature upto which the SOI diode’s characteristic remains linear. Thesemethods are as follows.

i) The maximum linear temperature can be calculated nu-merically by using the theory of nonlinear conduction insemiconductors [23], which relates the “threshold” of theon-set of a nonlinear effect to the cancellation of the thirdderivative. The method is based on building two aidingfunctions which comprise the negative of the originalfunction added to two linear asymptotes before and afterthe threshold point, respectively. At the intersection ofthese two new aiding functions one can find the positionof the threshold point. As demonstrated in [23] and [24],this intersection occurs when the third derivative of theoriginal function is equal to zero.1 The nonlinearity of the

- characteristics in our case comes from the presenceof the last term (i.e., 4th term) in (6). The third derivativeof this term was calculated using MATLAB and equatedto zero (note that other methods, such as, defining amaximum root means square error relative to a linearfunction can also be used). An example of the shape ofthe third derivative of the last term of (6) with respectto temperature is shown in Fig. 9 for a 100 drivingcurrent. The maximum operating temperatures foundfrom the MATLAB simulations with 100 , 10 , and

1This method is particularly useful in estimating the threshold voltages inMOSFETs.

Fig. 9. Third derivative of the nonlinear term of the diode voltage [last term of(6)] versus temperature for a diode driving current of 100 ��.

100 nA drive current are 615 C, 517 C, and 370 C,respectively.

ii) The maximum operating temperature can also be cal-culated by taking [18], where thethermal voltage now equates the voltage drop acrossthe diode. The physical interpretation of this is that thethermal voltage itself generates the whole voltage of thediode indicating the intrinsic character of the diode. In(6), the 4th term is now no longer negligible but equalto (kT/q) ln 2. Using this condition in (1), the followingtranscendental equation was arrived for the determinationof the temperature

(8)

By solving this equation graphically it was found thatwas 608 C, 510 C, and 364 C for the driving cur-

rent 100 , 10 and 100 nA, respectively.iii) In the third method, the maximum linear operation tem-

peratures were calculated when the driving current equalsto the saturation current. The physical explanation of thisis almost equivalent to that in ii) but looks at the transi-tion from extrinsic to intrinsic conduction from a currentperspective rather than a voltage perspective. The resultsis however very similar, as the 4th term in (6) becomesnon-negligible. From (1) and (2), we can get

(9)

The above transcendental was solved graphically and themaximum linear operation temperatures were calculated as632 C, 528 C, and 378 C for the driving current 100 ,10 , and 100 nA, respectively.

It can be seen that the maximum linear operation temperaturecalculated from all the three methods are quite close to eachother, and also match well with our experimental findings de-picted in Fig. 7.

The driving current versus the maximum operating tempera-ture [calculated from method i)] is also plotted in Fig. 10 to see

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1002 IEEE SENSORS JOURNAL, VOL. 10, NO. 5, MAY 2010

Fig. 10. Maximum operable temperature of SOI diode for different driving cur-rents.

the relation between the two. An empirical exponential func-tion was fitted through points to relate the maximum operabletemperature to the operating forward-bias current using the fol-lowing relationship:

(10)

where , , , , and , are constants. The values of theseconstants are 284.78, 142.07, , 192.17, and ,respectively.

It is worthwhile noting that increasing the driving currentand/or reducing the reverse saturation current (leakage current)

are the main ways to increase the maximum temperature op-erating range. This is because the 4th term (the 2nd nonlinearterm) in (6) is highly dependent on and .

VI. CONCLUSIONS

In this paper, we have reported upon the performance of anSOI diode at ultra-high temperatures (up to 780 C). The simu-lated and theoretical data are both in good agreement with theexperimental results. We have demonstrated an SOI diode, em-bedded in a silicon oxide-nitride membrane that can be used asa temperature sensor up to 550 C with a very linear forwardbias voltage response. The linearity maintained up to this hightemperature is due to the very low reverse saturation current,and a relatively high forward bias drive current . It was foundthat performance of the diode deteriorates beyond this temper-ature due to a rapid increase in the diode saturation current. In-creasing the saturation current above a certain level, no longerproduces a change in the maximum operating temperature andmoreover can result in undesirable self-heating. Continuous op-eration of the diode at 400 C and 500 C for 100 h shows thatthe diodes are fairly reliable as the maximum output voltagevariation recorded was only 1–2 mV corresponding to a tem-perature variation of approximately C.

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Sumita Santra received the M.Sc. degree in physicsfrom Calcutta University, Calcutta, India, in 1999,and the M.Sc. degree in physics and the Ph.D. degreein atomic physics and spectroscopy from the Saha In-stitute of Nuclear Physics, India, in 2001 and 2007,respectively.

She is currently a Research Associate with the Uni-versity of Cambridge, Cambridge, U.K. Her researchinterests include temperature sensors and gas sensors.She is also involved in fabrication and characteriza-tion of different nanomaterials on CMOS platform

for smart sensors.

Prasanta K. Guha received the B.Sc. (Hon) degreein physics and the B.Tech. degree in radiophysics andelectronics from the University of Calcutta, Calcutta,India, in 1997 and 2000, respectively, the M.Phil. de-gree from the Microelectronic Research Center, Uni-versity of Cambridge, Cambridge, U.K., in 2003, andthe Ph.D. degree in smart CMOS gas sensors fromthe Department of Engineering, University of Cam-bridge, in 2008.

He is presently a Research Fellow with the Uni-versity of Warwick, Warwick, U.K. His research in-

terests include smart CMOS sensors and interface electronics.

Syed Zeeshan Ali received the B.S. degree in elec-tronic engineering from the GIK Institute, Pakistan,in 2003 and the Ph.D. degree from the Universityof Cambridge, Cambridge, U.K., in 2007, focusingon CMOS micro-hotplates for smart gas sensors andelectro-thermo-mechanical modeling of membranedevices.

He is a Research Associate with the Universityof Cambridge, researching micro-hotplates andmaterials for smart gas sensors.

Ibraheem Haneef (M’07) received the B.Eng.degree from NED University, Karachi, Pakistan,the M.S. degree from the National University ofSciences and Technology (NUST), Islamabad, Pak-istan, in 1991 and 2004, respectively, and the Ph.D.degree from the Engineering Department, Universityof Cambridge, Cambridge, U.K., in 2009, focusingon design, packaging, and characterization of SOICMOS MEMS flow sensors.

He is currently an Assistant Professor with the In-stitute of Avionics and Aeronautics, Air University,

Islamabad, Pakistan. His research interests include CMOS MEMS flow sen-sors, pressure sensors, temperature sensors, gas sensors, and accelerometers.He is also interested in laser micromachining for MEMS and CNTs based gassensors and solar cells.

Florin Udrea received the M.Sc. degree in smart sen-sors from the University of Warwick, Warwick, U.K.,in 1992 and the Ph.D. degree in power devices fromthe University of Cambridge, Cambridge, U.K., in1995.

He is a Professor of Semiconductor Engineeringand Head of the High Voltage Microelectronics andSensors Laboratory, University of Cambridge. SinceOctober 1998, he has been an academic with the De-partment of Engineering, University of Cambridge.Between August 1998 and July 2003, he was an ad-

vanced EPSRC Research Fellow, and prior to this, a College Fellow in GirtonCollege, University of Cambridge. He is currently leading a research group inpower semiconductor devices and solid-state sensors that has won an interna-tional reputation during the last 15 years. He has published over 250 papers injournals and international conferences. He holds 50 patents with 30 more patentapplications in power semiconductor devices and sensors. He co-founded twocompanies, Cambridge Semiconductor (Camsemi) and Cambridge CMOS Sen-sors (CCS) in the fields of power ICs and smart sensors, respectively.

Dr. Udrea (Camsemi) received the 2009 Rosenblatt New Energy Award.Camsemi was awarded “University Spin-out of the Year” and the awardreflected Camsemi’s disruptive energy-saving technologies, “cost efficient”products, and sustained commitment to the green agenda. Previously, in 2008,the company received the Startup of the Year Award from NMI and was listedin top 100 cleantech companies in third position by The Guardian.

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