Home  |  Contact Us    

Start
Courses
Research
CV

Advanced SiC Devices
OptTool
SiC Properties

 

 

Research 

I am working as a senior researcher in the electronics design division at Mid-Sweden University in Sundsvall. Some of the projects that I am (or have been) involved in are:

High Speed Switch mode Power Supplies

The aim of the research is to develop switch mode power supplies working in the MHz region where passive components can be made smaller and reducing the overall price and size of the supply.

Infrared detector for CO2 detection

 

Device Optimization Tool

Device design is a time-consuming work, where the influence of many design parameters has to be investigated thoroughly. In advanced devices, optimum performance is often achieved taking multiple trade-offs into consideration, and manual device optimization is insufficient.

An Optimization Tool is developed, which runs device simulations and automatically changes the design parameters. The tool searches for optimum performance according to a specified performance measure. This has been shown to be a very time- and cost-effective method for device design, as the search for optimum performance is working systematically 24 hours, 7 days a week. From an industrial point of view this is very important, as it can reduce the evaluation and optimization cost for new devices considerably.

SiC Material Properties

Silicon carbide is a very promising material for use in high-power and high-frequency devices. The reason for this the favorable transport parameters in SiC. The saturation velocity is twice the value for silicon and the breakdown electrical field is almost ten times higher. The material properties are primary studied in a full band Monte Carlo simulator. Some of the most important SiC Material properties

SiC Device simulations

Silicon Carbide devices will probably be commercial available in a few years and the areas where is is most likely to be introduced is in: 

bulletHigh power, switching and rectifying devices.
bulletHigh temperature electronics.
bulletHigh frequency, power devices.

In the devices simulation performed at Sundsvall we have worked with the following devices.

bulletSiC Diodes
bulletSiC MESFETs
bulletSiC MOSFETs
bulletSiC vertical MESFETs

Position sensitive detectors

We have designed, manufactured and characterized a low atmospherical-noise four-quadrant position sensitive silicon detector (PSD).

Fiber Optic Devices and Communications

Research within fiber-optic communication are under startup and a short introduction to the topic has been presented in a seminar held at Mid-Sweden University. The presentation is divided into two parts: "Optical fibers and Fiber amplifiers" and "Optical Devices and Soliton Systems".

List of Publications

  1. J. Saleem, A. Majid, K. Bertilsson, T. Carlberg, “Spot welding Al 6082 sheets with preheating by induction heating process", submitted to Journal of Electrical engineering and Technology

  2. A. Majid, J. Saleem, F. Alam,  K. Bertilsson “Analysis of radiated EMI for power converters switching in MHz frequency range”, IEEE International symposium on diagnostics for Electric Machines, Power Electronics and Drives August 27-30, 2013, Valencia.

  3. J. Saleem, A. Majid, K. Bertilsson, T. Carlberg “3 Dimensional Finite Element Simulation of Seam Welding Process” Journal of elektronika ir Elektrotechnika ISSN 1392-1215, Vol 19, No 8, pp. 75-80, 2013, DOi: 10.5755/j01.eee.19.8.5398

  4. A. Majid, J. Saleem, F. Alam,  and K. Bertilsson, “EMI Suppression in High Frequency (MHz) Half Bridge Converter”, Journal of elektronika ir Elektrotechnika  ISSN 1392-1215, Vol 19, No 8, pp 73-78,  DOi: 10.5755/j01.eee.19.9.5653

  5. K. Bertilsson, "Compact power converter", Invited presentation at Workshop on Silicon Carbide Power Electronic Applications, June 2013, Stocholm, Sweden

  6. H. B. Kotte, R. Ambatipudi and K. Bertilsson, "A 45W LLC resonant Converter in MHz Frequency Region for Laptop Adapter Applications", PCIM 2013, Nürnberg, May 2013

  7. R. Ambatipudi, H. K. Babu, K. Bertilsson, "High Performance Planar Power Transformer with High Power Density in MHz Frequency Region for Next Generation Switch Mode Power Supplies", 28th Annual IEEE Applied Power Electronics Conference and Exposition (APEC 2013), p 2139-43, 2013, DOi: 10.1109/APEC.2013.6520591

  8. H. B. Kotte, R. Ambatipudi and K. Bertilsson, “High Speed (MHz)Series Resonant Converter (SRC) Using Multilayered Coreless Printed Circuit Board (PCB) Step-Down Power Transformer",  IEEE transaction of Power electronics Vol. 20, No 3, 2013

  9. J. Saleem, A. Majid, K. Bertilsson, T. Carlberg, N. Ul Islam, "Nugget Formation during Resistance Spot Welding
    using Finite Element Model",     International Conference on Aerospace, Mechanical, Automotive and Materials Engineering, Stockholm 2012

  10. A. Majid, J. Saleem, K. Bertilsson, "Design and Implementation of EMI Filter For High Frequency (MHz) Power Converters", Proceeding of EMC Europe 2012, 17-21 September, 2012, Rome, DOi: 10.1109/EMCEurope.2012.6396738

  11. A. Majid, J. Saleem, K. Bertilsson, "EMI filter design for high frequency power converters", proceedings of IEEE International Conference on Environment and Electrical Engineering, Venice, May 2012

  12. K. Bertilsson, "Nästa generations kompakta spänningsomvandlare", THULE, Kungl. Skytteanska Samfundets årsbok 2012, Umeå, pp. 153-157

  13. R. Ambatipudi, H. K. Babu, K. Bertilsson, “Effect of Air Gap on the Performance Characteristics of Transformer for High Frequency (MHz) Switch Mode Power Supplies“, Accepted for publication in INDUCTICA 2012, Coil Winding, Insulation and Electrical Manufacturing International

  14. R. Ambatipudi, H. K. Babu, K. Bertilsson, “Effect of Dielectric Material on the Performance of Printed Circuit Board Power Transformers in MHz Frequency Region", Accepted for publication in INDUCTICA 2012, Coil Winding, Insulation and Electrical Manufacturing International

  15. H. B. Kotte, R. Ambatipudi, S. Haller , K. Bertilsson, “A ZVS Half Bridge DC-DC Converter in MHz Frequency Region Using Novel Hybrid Power Transformer”, in Proceedings of PCIM Europe 2012, 8 – 10 May 2012, Nuremberg, Germany, pp.399 – 406

  16. H. B. Kotte, R. Ambatipudi and K. Bertilsson, “High Speed Series Resonant Converter (SRC) Using Multilayered Coreless Printed Circuit Board (PCB) Step-Down Power Transformer”, proceedings of 33rd International Telecommunicatons Energy Conference, 9-13 October 2011, Amsterdam, The Netherlands.

  17. J. Saleem, A. Majid, S. Haller, K. Bertilsson, "A Study of IGBT Rupture Phenomenon in Medium Frequency Resistance Welding Machine" , International Aegean Conference on Electric Machines and Power Electronics & Electromotion, 08-10 September 2011 İstanbul, Turkey

  18. A. Majid, J. Saleem, H. B. Kotte, R. Ambatipudi, S. Haller, K .Bertilsson,”Analysis of Feedback in Converter using Coreless Printed Circuit Board Transformer”, International Aegean Conference on Electrical Machines and Power Electronics & Electromotion-ACEMP 2011 at Turkey Istambul (September 08-10, 2011)

  19. J. Saleem, A. Majid, R. Ambatipudi, H. B. Kotte, Kent Bertilsson, "High Frequency Full Bridge Converter using Multilayer Coreless Printed Circuit Board Step-Up Power Transformer" 20th European Conference on Circuit Theory and Design, ECCTD2011, August 29 to 31, 2011 Linköping, Sweden

  20. A. Majid, H. B. Kotte, S. Haller, R. Ambatipudi, J. Saleem, K. Bertilsson "High Frequency Half-Bridge Converter using Multilayered Coreless Printed Circuit Board Step-Down Power Transformer", proceedings of 8th Internastional Conference on Power Electronics-ECCE Asia, June 2011, Jeju, Korea

  21. R. Ambatipudi, H. B. Kotte, K. Bertilsson, "Radiated Emissions of Multilayered Coreless Printed Circuit Board Step-Down Power Transformers in Switch Mode Power Supplies", proceedings of 8th Internastional Conference on Power Electronics-ECCE Asia, June 2011, Jeju, Korea

  22. H. B. Kotte, R. Ambatipudi, K. Bertilsson, "High Speed Cascode Flyback Converter Using Multilayered Coreless Printed Circuit Board (PCB) Step-Down Power Transformer", proceedings of 8th Internastional Conference on Power Electronics-ECCE Asia, June 2011, Jeju, Korea

  23. J. Saleem, A. Majid, L. Schüberg, and K. Bertilsson, "Study the influence of the alignment and nearby metallic objects on the Hall sensor system for current measurement in Resistance Spot Welding Machine", proceedings of IEEE International Conference on Environment and Electrical Engineering 2011, May 2011, Rome, Italy

  24. K. Bertilsson, "High frequency power converters", Invited presentation at Workshop on Silicon Carbide Power Electronic Applications, May 2011, Kista, Sweden,

  25. R. Ambatipudi, H. B. Kotte and K. Bertilsson, “Comparison of Two Layered and Three Layered Coreless Printed Circuit Board (PCB) Step-down Transformers”, proceedings of 2010 3rd The International Conference on Power Electronics and Intelligent Transportation System (PEITS 2010)”, November 20-21, 2010, Shenzhen, China.

  26. H. B. Kotte, R. Ambatipudi and K. Bertilsson, “Comparitive results of GaN and Si MOSFET in a ZVS Flyback Converter using Multilayered Coreless Printed Circuit Board Step down Transformer”, proceeding of 2010 3rd The International Conference on Power Electronics and Intelligent Transportation System (PEITS 2010)”, November 20-21, 2010, Shenzhen, China. .

  27. R. Ambatipudi, H. B. Kotte and K. Bertilsson, “Coreless Printed Circuit Board (PCB) Step-down Transformers for DC-DC Converter Applications”, Int. Conference on Electrical Machines and Power Electronics, Issue 71, ISSN: 1307-6892, pp. 370-379, 2010.

  28. Hari. B. Kotte, R. Ambatipudi and K. Bertilsson, ‘’A ZVS Flyback DC-DC Converter using Multilayered Coreless Printed-Circuit Board (PCB) Step-down Power Transformer”, Int. Conference on Electrical Machines and Power Electronics, Issue 71, ISSN: 1307-6892, pp. 80-88, 2010

  29. C. G Mattsson, G. Thungström, K. Bertilsson, H.-E. Nilsson and H. Martin, "Fabrication and characterization of a design optimized SU-8 thermopile with enhanced sensitivity", Measuremenst Science and Technology, 20, 2009

  30. C. G. Mattsson, G. Thungström, H. Rödjegård, K. Bertilsson, H.-E. Nilsson, H. Martin, "Experimental evaluation of a thermopile detector with SU-8 membrane, in a carbon dioxide meter setup", IEEE Sensors Journal, Vol. 9, No. 12, 2009

  31. C. G. Mattsson, K. Bertilsson, G. Thungström, H.-E. Nilsson and H. Martin, "Thermal simulation and design optimization of a thermopile infrared detector with SU-8 membrane", Micromachnics and Microengineering, Vol 19, No. 5, 2009

  32. C. G. Mattsson, G. Thungström, K. Bertilsson, H.-E. Nilsson, Hans Martin, "Design of a Micromachined Thermopile Infrared Sensor With a Self-Supported Membrane", IEEE Sensors Journal, Vol. 8, No. 12, 2008, pp. 2044-2052

  33. H. A. Andersson, K. Bertilsson, G. Thungström, H.-E. Nilsson, "Processing and Characterization of a MOS-Type Tetra Lateral Position Sensitive Detector With Indium Tin Oxide Gate Contact", IEEE Sensors Journal, Vol. 8, No. 10, 2008, pp. 1704-1709

  34. C. G. Mattsson, G. Thungström, K. Bertilsson, H.-E. Nilsson, "Fabrication and evaluation of a thermoelectric IR sensor formed on a thin photosensitive epoxy membrane with low thermal conductance" in Journal of Physics: Conf. series, IVC-17 / ICSS-13 and ICN+T 2007 congress, 2007,

  35. C. G. Mattsson, G. Thungstrom, K. Bertilsson, H.-E. Nilsson, H Martin, "Development of an infrared thermopile detector with a thin self-supporting SU-8 membrane", IEEE Sensors Conference, 2007, pp. 836-839

  36. K. Bertilsson, C. I. Harris, "Comparison of Bipolar and Unipolar SiC Switching Devices for Very High Power Applications", Materials Science Forum Vols. 556-557, 2007, pp. 975-978

  37. S. Intarasiri, A. Hallén, J. Lu, J. Jensen, L. D. Yu, K. Bertilsson, M. Wolborski, S. Singkarat, and G. Possnert, “Crystalline quality of 3C-SiC formed by high-dose C+-implanted Si”, Applied Surface Science, Volume 253, Issue 11, 2007, pp. 4836-4842

  38. M. O'nils, B. Oelmann, K. Bertilsson, G. Thungström, H.-E. Nilsson, "A Project Based Master’s Program for SoF/SoC based Sensor Systems", Proceedings of the European Conference on Circuit Theory and Design, 2005.

  39. * K. Bertilsson, C. Harris, H-E. Nilsson, "Calculation of lattice heating in SiC RF power devices", Solid State Electronics Vol 48 (12), 2004, pp. 2103-2107.

  40. * K. Bertilsson, H-E. Nilsson, "The power of using automatic device optimization, based on iterative device simulations, in design of high-performance devices", Solid State Electronics Vol 48 (10-11), 2004, pp 1721-1725.

  41. C. Mattsson, K. Bertilsson, G. Thungström, H.-E. Nilsson, "Manufacturing and characterization of a modified four quadrant position sensitive detector for out-door applications", Nuclear Instruments and Methods in Physics Research A 531, 2004, pp. 134–139

  42. K. Bertilsson, H.-E. Nilsson, “Optimization of 2H, 4H and 6H-SiC MESFETs for High Frequency Applications”, Physica Scripta T101, 2002, pp.75-77

  43. * E. Dubaric, K. Bertilsson, H.-E. Nilsson, “Simulations of Submicron MOSFETs in 2H, 4H and 6H-SiC”, Physica Scripta T101, 2002, pp. 14-17

  44. H.-E. Nilsson, E. Dubaric, M. Hjelm, K. Bertilsson, “Simulation of photon and charge transport in X-ray imaging semiconductor sensors”, Nuclear Instruments and Methods in Physics Research A 487, 2002, pp.151-162

  45. * H.-E. Nilsson, K. Bertilsson, M. Hjelm, E. Dubaric, “Numerical Simulation of Field Effect Transistors in 4H- and 6H-SiC”, Journal of Wide Bandgap Materials, Vol. 9, No. 4, 2002, pp. 293-305.

  46. * K. Bertilsson, H.-E. Nilsson, “Optimization of 2H, 4H and 6H-SiC high-speed vertical MESFETs”, Diamond and Related Materials No. 11, 2002, pp. 1254-1257.

  47. K. Bertilsson, M. Hjelm, H.-E. Nilsson, C. S. Petersson, “Monte Carlo Simulation of 4H and 6H-SiC short channel MOSFETs”, Proceedings of HITEN 2001, pp. 79-80.

  48. * M. Hjelm, K. Bertilsson, H.-E. Nilsson, “Full Band Monte Carlo Study of Bulk and Surface Transport Properties in 4H and 6H-SiC”, Applied Surface Science No. 184, 2001 pp. 194-198.

  49. K. Bertilsson, E. Dubaric, G. Thungström, H.-E. Nilsson, C. S. Petersson, “Simulation of a low atmospherical noise four-quadrant position sensitive detector”, Nuclear Inst. and Methods in Physics Research, A, Vol 466 (1), 2001,  pp. 183-187.

  50. * K. Bertilsson, H.-E. Nilsson, M. Hjelm, C. S. Petersson, P. Käckell, C. Persson, “The Effect of Different Transport Models in Simulation of High Frequency 4H-SiC and 6H-SiC Vertical MESFETs”, Solid-State Electronics, Vol 45 (5), 2001, pp. 645-653.

  51. * K. Bertilsson, E. Dubaric, H.-E. Nilsson, M. Hjelm, C. S. Petersson, “Monte Carlo simulation of vertical MESFETs in 2H, 4H and 6H-SiC”, Diamond and Related Materials No. 10, 2001, pp. 1283-1286

  52. * K. Bertilsson, H.-E. Nilsson, C. S. Petersson, “Simulation of anisotropic Breakdown in 4H-SiC Diodes”, Proceeding of Computers in Power Electronics -2000, Virginia Tech, Blacksburg, Virginia, USA, 16-18 July 2000.

* - Included in Ph.D. Thesis, Kent Bertilsson, “Simulation and Optimization of SiC Field Effect Transistors”, ISSN 1650-8599, KTH, Stockholm, 2004

 

Patents and patent applications

  1. K. Bertilsson, "A transformer", EP2242067A1

  2. K. Bertilsson, "Transformer", US7,978,041 B2

  3. C. Harris, K. Bertilsson, A. Konstantinov, "Silicon Carbide self aligned epitaxial MOSFET and method of manufacturing the same", JP2008227486,

  4. C. Harris, K. Bertilsson, A. Konstantinov, "Silicon Carbide self aligned epitaxial MOSFET and method of manufacturing thereof", EP1965436

  5. C. Harris, K. Bertilsson, A. Konstantinov, "Silicon Carbide self aligned epitaxial MOSFET and method of manufacturing thereof", US20080203398

  6. C.Harris, K. Bertilsson, . Konstantinov, "Method of manufacturing Silicon Carbide self-aligned epitaxial MOSFET for highe powered device applications", US20100041195

  7. C. Harris, C. Basceri, K. Bertilsson, "Schottky Diode with incorporated PN-junctions", EP2033226

  8. C. Harris, C. Basceri, K. Bertilsson, "Schottky Diode with incorporated PN-junctions",WO2007139487

  9. C. Harris, K. Bertilsson, A. Konstantinov, "Silicon Carbide self aligned epitaxial MOSFET and method of manufacturing thereof", US7629616

  10. C. Harris, C. Basceri, K. Bertilsson, "Semiconductor device", US20070278609

  11. C. Harris, C. Basceri, K. Bertilsson, "Semiconductor device", US7728403

  12. H.-E. Nilsson, H. Olin, K. Bertilsson, M. Hummelgård "Nanoelectronic device" in Swedish Patent Application no 0501443-6, 2005
Kent Bertilsson

Kent.Bertilsson@miun.se

Phone:  +4660 148915
Fax:   +4660 148456
Cellular:  +4670 6864443

_______________________

Visiting adress:

Kent Bertilsson
Mid-Sweden University
Åkroken-S 205
Holmgatan 10
Sundsvall

Mailing adress:

Kent Bertilsson
ITM
Mid-Sweden University
S-851 70 Sundsvall
Sweden

 
Copyright © 2004 Kent Bertilsson, Mid-Sweden University.   |  Site Map  |  Contact Us