Keith Heasman

Dr Keith Heasman


Quality Assurance Manager
Ph-D
+44 (0)1483 682214
17 NC 00
8:30am to 5:30pm

Academic and research departments

Advanced Technology Institute.

Biography

Biography

Keith graduated with a First Class BSc in Physics from the University of Surrey in 1981, and subsequently obtained his PhD in 1985 from the Optoelectronics group in the same department having carried out research on the temperature and pressure dependence of bulk and multi quantum well GaInAsP / InP semiconductor materials, Gunn diodes, LED's and Lasers. Following post graduate studies in the physics department on strained and unstrained quantum well lasers and then as the Philips Fellow in the Electrical Engineering department of the University of Surrey researching Erbium ion implantation into GaAlAs / GaAs quantum well structures Keith left Surrey University and between 1988 and 2004 he was employed as a physicist by BP and subsequently BP Solar, working in silicon solar cell research and development. In 2004 he joined Narec to initially set up the PV Technology Centre and then to enable it to grow and become the world's leading supplier of bespoke silicon concentrator cells. Whilst with BP Solar and Narec, Keith contributed to numerous European and UK funded research projects as well as running, and maintaining several characterisation laboratories dedicated to supporting the companies silicon solar cell manufacturing operations. Keith joined the Surrey Ion Beam Centre as the EPSRC funded Ion Implantation Research Fellow in February 2012.

Research interests

Photovoltaics, Concentrated Photovoltaics, Design, fabrication and characterisation of silicon solar cells, Ion Implantation, Optoelectronics, Semiconductor Lasers, Silicon photonics

Research collaborations

Current and previous collaborators include:Philips Research Laboratories, Fraunhofer Institute for Solar Energy Systems ISE, ENEA Portici, Whitfield Solar, Solar Energy Institute of the Technical University of Madrid, University of Konstanz, Centre for Renewable Energy Systems Technology Loughborough University, Heriot-Watt University, University of Exeter

My publications

Publications

KC Heasman, R Russell, TM Bruton, NB Mason (1996)The Development of Modules Containing High Efficiency Coloured Silicon Solar Cells for use in Building Integration, In: Proceedings 11th German National Symposium PV Solarenergiepp. 505-509
Jérémy Barbé, Harrison K. H. Lee, Hiroyuki Toyota, Kazuyuki Hirose, Shin-ichiro Sato, Takeshi Ohshima, Keith Heasman, Wing C. Tsoi (2018)Characterization of stability of benchmark organic photovoltaic films after proton and electron bombardments, In: Applied Physics Letters113(18)183301 AIP Publishing

Organic solar cells have attractive potential for space applications as they have very high specific power (power generated per weight) and ultra-high flexibility (to reduce stowed volume). However, one critical issue is whether they are stable under the harsh space environment, particularly their stability under high energy, high flux, electron and proton bombardment. In this paper, the stability of benchmark organic photovoltaic layers under proton bombardment (150 keV with a fluence of 1 × 1012/cm2) and electron bombardment (1 MeV with a fluence of 1 × 1013/cm2) under vacuum is investigated. Raman spectroscopy, photoluminescence spectroscopy, and optical reflectance spectroscopy are applied to study their chemical/structural, photo-chemical/morphological, and optical stability after the bombardments. The results show that all the benchmark organic photovoltaic films are stable under the radiation, implying that organic solar cells could be feasible for space applications.

KC Heasman, M Glatthaar, C Schmiga, S Devenport, DJ Morrison (2012)Development of Rear Passivated Laser Grooved Buried Contact (LGBC) Laser Fired Contact (LFC) Silicon Solar Cells Using Thin Wafers., In: Proceedings 27th European PV Solar Energy Conferencepp. 1512-1515
A Cole, KC Heasman, A Mellor, S Roberts, TM Bruton (2006)Laser grooved buried contact solar cells for concentration factors up to 100x, In: Conference Record of the 2006 IEEE 4th World Conference on Photovoltaic Energy Conversion, Vols 1 and 2pp. 834-837 IEEE
KC Heasman, TM Bruton, S Roberts, A Cole (2007)Laser Grooved Buried Contact Concentrator Cells
KC Heasman, TM Bruton, S Devenport, I Baistow, M Brown, S Roberts, A Cole (2011)Development of Laser Grooved Buried Contact Solar Cells for Use at Concentration Factors up to 100X
KC Heasman, T Bruton, L Brown, A Cole, K Drew (2009)Front Dicing Technique for Pre-isolation of Concentrator Silicon Solar Cells
KC Heasman (2006)Design and Optimisation of Laser Grooved Buried Contact Solar Cells for Use At Concentration Factors Up To 100X, In: Proceedings 21st European PV Solar Energy Conference
KC Heasman, A Cacciato, F Duerinckx, K Baert, E Tonelli, F Ferrazza, C Busto, D Antonelli, JW Muller, M Scherff, MB Kontopp, SW Glunz, B Weber, C Schmiga, B Michl, P Saint-Cast, C Ballif, S De Wolf, Z Holman, S Devenport, D Morrison, G Hahn, J Ebser, S Seren, Y Schiele, R Horbelt, B Terheiden (2012)The European Project 20plµs: 20 Percent Efficiency on Less Than 100µm Thick Industrially Feasible c-Si Solar Cells., In: Proceedings 27th European PV Solar Energy Conference
H Baig, KC Heasman, N Sarmah, T Mallick (2012)Solar Cells Design For Low And Medium Concentrating Photovoltaic Systems, In: 8TH INTERNATIONAL CONFERENCE ON CONCENTRATING PHOTOVOLTAIC SYSTEMS (CPV-8)1477pp. 98-101 AMER INST PHYSICS
KC Heasman, MJ O'Neill, R Russell, NB Mason, JP Nagle, TM Bruton (1992)Recent Developments in Concentrator Cells & Modules Using Silicon Laser Grooved Buried Grid Cells, In: Proceedings 11th EC PV Solar Energy Conferencepp. 1042-1044
S Devenport, S Roberts, KC Heasman, A Cole, D Tregurtha, TM Bruton (2008)PROCESS OPTIMISATION FOR COLOURED LASER GROOVED BURIED CONTACT SOLAR CELLS, In: PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4pp. 414-417
KC Heasman, TM Bruton, S Roberts, A Mellor, A Cole (2006)Device Design and Process Optimisation for LGBC Solar Cells for Use Between 50X and 100X Concentration, In: Proceedings EUROSUN
KC Heasman, EB Cowern, L Brown, A Cole, K Drew, C Ahn (2010)INTEGRATED PROCESS AND DEVICE ‘TCAD’ FOR ENHANCEMENT OF C-SI SOLAR CELL EFFICIENCY
KC Heasman, S Dewallef, TM Bruton, DJ Morrison, K Drew, S Devenport, LM Brown, A Cole, L Pirozzi, E Salza, M Tucci, M Izzi, S Iuliis, L Serenelli (2010)SCREEN PRINTING IN LASER GROOVED BURIED CONTACT SOLAR CELLS: THE LAB2LINE HYBRID PROCESSES, In: Proceedings 25th European PV Solar Energy Conference
KC Heasman, TM Bruton, JP Nagle, DW Cunningham, NB Mason, R Russell, MA Balbuena (1994)Recent Progress in the Production of High Efficiency Laser Grooved Buried Grid Silicon Solar Cells
G Timò, A Martinelli, A Minuto, B Schineller, I Sagnes, R Jakomin, G Beaudoin, N Gogneau, M Noack, S Padovani, S Borshchov, R Kenny, A Sarno, GE Georghiou, P Zurru, M Sturm, M Wild-Scholten, G Bellia, G Gigliucci, E Medina, K Heasman, G Martinelli (2009)First results on the APOLLON project multi-approach for high efficiency integrated and intelligent concentrating PV modules (systems), In: Conference Record of the IEEE Photovoltaic Specialists Conferencepp. 002424-002429

Next generation concentrating photovoltaic technologies could have a large-scale impact on world electricity production once they will become economically attractive and grid parity will be reached. To proceed towards this important goal, a new large integrated project, APOLLON, has started in July 2008, within the frame of the 7th European Framework program, having the main objective of substantial decrease the Concentrating Photovoltaic (CPV) technology cost to a target value of 2 Euro/W. This ambitious objective is targeted to be reached after five years of research and technological activities in which, both "point focus" and "dense array" CPV technologies will be implemented by facing all the technology-critical issues related to each component of the CPV systems. With this contribution we report the principal results obtained during the first year of the project regarding Multi-Junction (MJ) solar cells, concentrator optics, assembling, tracking and testing. ©2009 IEEE.

KC Heasman, J Knobloch, J Dicker, SW Glunz, W Warta, R Russell, S Roberts, TM Bruton (2000)Prospects For High Efficiency Silicon Solar Cells In Thin Czochralski Wafers Using Industrial Processes, In: Proceedings 28th IEEE PVSEC Confpp. 180-183
KC Heasman, L Pirozzi, M Tucci, M Izzi, E Salza, S de Iuliis, L Serenelli, TM Bruton, D Morrison, S Devenport, LM Brown, A Cole (2009)THE LAB2LINE LASER GROOVED BURIED CONTACT SCREEN PRINTED SOLAR CELLS HYBRID P-TYPE MONOCRYSTALLINE PROCESSpp. 1318-1322
I Anton, G Sala, K Heasman, R Kern, TM Bruton (2003)Performance prediction of concentrator solar cells and mdules from dark I-V characteristics, In: PROGRESS IN PHOTOVOLTAICS11(3)pp. 165-178 JOHN WILEY & SONS LTD
G Claudio, K Bass, K Heasman, A Cole, S Roberts, S Watson, M Boreland (2009)Surface passivation by silicon nitride in Laser Grooved Buried Contact (LGBC) silicon solar cells, In: SUPERLATTICES AND MICROSTRUCTURES45(4-5)pp. 234-239
T Bruton, S Roberts, N Mason, K Heasman (2005)Low cost, 100X point focus silicon concentrator cells made by the LGBC process, In: Conference Record of the IEEE Photovoltaic Specialists Conferencepp. 647-650

LGBC silicon solar cells have demonstrated efficiencies up to 20% when used in linear focus concentrating systems up to 20X concentration. Small area cells of 1.2 cm2 have been cut from these cells and tested up to 100X concentration for point focus applications. A potential to achieve 20% efficiency at 100X has been recognised and independent results to date have shown an efficiency approaching 18% at 100X. Based on simple variations of a mass production process, analysis indicates that the manufacturing cost for such cells can be below $0.15/Wp. ©2005 IEEE.

YS Tang, J Zhang, KC Heasman, BJ Sealy (1989)Lattice locations of erbium implants in silicon, In: Solid State Communications72(10)pp. 991-993

The lattice locations of erbium implanted in silicon were studied by backscattering angular scanning in combination with photoluminescence measurements. The results show that the positions of erbium implants depend on annealing conditions and have tetrahedral and/or orthorhombic symmetries in different cases. © 1989.

KC Heasman, N Mason, T Bruton, S Gledhill, O Hartley, C Morilla, S Roberts (2004)The Selection and Performance of Monocrystalline Silicon Substrates for Commercially Viable 20% Efficient, LID-free Solar Cells., In: Proceedings 19th European PV Solar Energy Conference
KC Heasman, TM Bruton, P Gibbard, S Devenport, A Cole, L Brown (2010)LGBC Silicon Solar Cell with modified bus bar suitable for high volume wire bonding
KC Heasman, TM Bruton, S Roberts (2000)The Reduction of Module Power Losses by Optimisation of the Tabbing Ribbonpp. 2378-2382
KC Heasman, DW Cunningham, RW Russell, TM Bruton, S Roberts (1998)Interdigitated-Contact Silicon Silicon Solar Cells Made Without Photolithographypp. 1449-1452
KC Heasman, AW Webber, CJJ Tool, P Manshanden, H Tathgar, O Gjerstad, M McCann, B Raabe, F Huster, P Fath, S Ponce-Alcantara, J Coello, C del Canzio, S Roberts, TM Bruton, H Hagel, B Lenkeit, W Schmidt, R Russell (2006)Record Cell Efficiencies on mc-Si and a roadmap towards 20%, the EC Project TOPSICLE., In: Proceedings 21st European PV Solar Energy Conference
KC Heasman, TM Bruton, S Roberts, A Mellor, A Cole (2006)Laser Grooved Buried Contact Solar Cells for Concentration Factors up to 100X, In: Proceedings 4th WCPECpp. 834-837
KC Heasman, TM Bruton, NB Mason, R Russell, Nast-Hartley (2002)Investigation Of Thin Aluminium Films On The Rear Of Monocrystalline Silicon Solar Cells For Back Surface Field Formation, In: Proceedings 29th IEEE PVSEC Conferencepp. 118-121
KC Heasman, J Wilson, B Richards, A Pereau, G Kocher, J Delve, S Devenport, A Cole, D Morrison (2009)Development of Laser Fired Contact (LFC) Rear Passivated Laser Groove Buried Contact (LGBC) Solar Cells Using Thin Wafers
KC Heasman, TM Bruton, D Morrison, S Devenport, LM Brown, A Cole (2017)Progress of the LAB2LINE Laser Grooved Buried Contact Screen Printed Solar Cells Hybrid p-type Monocrystalline Process, In: 03/04/2009
KC Heasman, R Russell, NB Mason, DW Cunningham, TM Bruton, S Roberts (1995)High Efficiency Production Silicon Solar Cells with Screen Printed Contacts
H Baig, N Sarmah, KC Heasman, TK Mallick (2013)Numerical modelling and experimental validation of a low concentrating photovoltaic system, In: Solar Energy Materials and Solar Cells113pp. 201-219

Concentrator solar cells need to be designed optimally depending on the concentrating photovoltaic (CPV) system, application and operating conditions to ensure the best system performance. The important factors while designing include concentration ratio, cell material properties, expected operating temperature, cell shape, bus bar configuration, number of fingers their size and spacing. The irradiation incident on the solar cell while being concentrated experiences several losses caused by the different physical phenomena's occurring in the system. A particular issue for CPV technology is the non-uniformity of the incident flux on the solar cell which tends to cause hot spots, current mismatch and reduce the overall efficiency of the system. Understanding of this effect and designing the cell while considering these issues, would help in improving the overall performance of the system. This study focuses on modelling a low concentrating photovoltaic system used for building integration, optimising the cell metallisation and analysing the effects of temperature on the overall output of the system. The optical analysis of the concentrator is carried out using ray tracing and finite element methods to determine electrical and thermal performance under operating conditions. Furthermore, an analysis is made to understand the effects of non-uniformity on the output of the device. About 0.5% absolute drop in solar cell efficiency was observed due to non-uniformity at 5o incident angle. A relative drop of 1.85% was observed in the fill factor due to non-uniformity of the flux distribution. A maximum cell temperature of 349.5 K was observed across the cell in both uniform and non-uniform conditions under an incident solar radiation of 1000 W/m2 which further reduced the performance of the solar cell. The solar cell design was also analysed by varying the number of fingers and the optimum grid design reported. A small prototype concentrator based on the design proposed was made using polyurethane and tested experimentally with the optimized solar cell design. On comparing the results obtained using the experimental data a good agreement in the system output could be seen. The difference in the overall system output was seen to be of the order of 11% which could be due to several losses occurring in the prototype which were not accounted in the model. © 2013 Published by Elsevier B.V. All rights reserved.

JL Colaux, C Jeynes, KC Heasman, RM Gwilliam (2015)Certified ion implantation fluence by high accuracy RBS, In: ANALYST140(9)pp. 3251-3261 ROYAL SOC CHEMISTRY
P BLOOD, ED FLETCHER, K WOODBRIDGE, KC HEASMAN, AR ADAMS (1989)INFLUENCE OF THE BARRIERS ON THE TEMPERATURE-DEPENDENCE OF THRESHOLD CURRENT IN GAAS ALGAAS QUANTUM WELL LASERS, In: IEEE JOURNAL OF QUANTUM ELECTRONICS25(6)pp. 1459-1468 IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
KC Heasman, S Devenport, S Roberts, D Tregurtha, A Cole, TM Bruton (2008)Process optimisation for coloured laser grooved buried contact solar cells, In: Proceedings Photovoltaic Specialists Conference
KC Heasman, A Cole, S Roberts, S Devenport, TM Bruton (2008)Laser Grooved Buried Contact Concentrator Solar Cells, In: Proceedings 4th PVSAT Conference
TM BRUTON, KC HEASMAN (1993)THE ACHIEVEMENT OF 20-PERCENT EFFICIENCY IN A CZ SILICON SOLAR-CELL UNDER CONCENTRATION, In: CONFERENCE RECORD OF THE TWENTY THIRD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE - 1993pp. 1250-1251
KC Heasman, TM Bruton, S Roberts, KC Heasman, A Cole, D Tregurtha, S Devenport (2008)Colour and Shape in Laser Grooved Buried Contact Solar Cells for Applications in the Built Environment, In: Proceedings 23rd European PV Solar Energy conferencepp. 3516-3519
ON Hartley, R Russell, KC Heasman, NB Mason, TM Bruton (2002)Investigation of thin aluminium films on the rear of monocrystalline silicon solar cells for back surface field formation, In: CONFERENCE RECORD OF THE TWENTY-NINTH IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE 2002pp. 118-121
TM Bruton, S Roberts, KC Heasman, R Russell, W Warta, SW Glunz, J Dicker, J Knobloch (2000)Prospects for high efficiency silicon solar cells in thin Czochralski wafers using industrial processes, In: CONFERENCE RECORD OF THE TWENTY-EIGHTH IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE - 2000pp. 180-183
KC Heasman, A Cole, S Roberts, TM Bruton, L Pirozzi, L Serenelli, M Izzi, M Tucci, E Salza (2008)Studying the Groove Profiles Produced for Fine Line Screen Printed Front Contacts in Laser Grooved Buried Contact Solar Cells., In: Proceedings 4th PVSAT Conference
TM Bruton, J Sherborne, KC Heasman, CM Ramsdale (2002)Concepts for the manufacture of silicon solar cell modules for use in concentrating systems up to 5x., In: CONFERENCE RECORD OF THE TWENTY-NINTH IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE 2002pp. 1366-1368
KC Heasman, P Martufi, M Tucci, M Izzi, L Serenelli, L Pirozzi, TM Bruton, D Tregurtha, S Roberts, A Cole (2008)FINE-LINE SCREEN PRINTING IN LARGE AREA LASER GROOVED, BURIED CONTACT SILICON SOLAR CELLS, In: Proceedings 23rd European PV Solar Energy conferencepp. 1677-1681
H Baig, KC Heasman, TK Mallick (2012)Non-uniform illumination in concentrating solar cells, In: Renewable and Sustainable Energy Reviews16(8)pp. 5890-5909

After a gap of more than two decades, Concentrator Photovoltaics (CPV) technology is once again under spotlight for making use of the best available solar cell technologies and improving the overall performance. CPV finds its use in a number of applications ranging from building integration to huge power generation units. Although the principles of solar concentration are well understood, many practical design, operation, control issues require further understanding and research. A particular issue for CPV technology is the non-uniformity of the incident flux which tends to cause hot spots, current mismatch and reduce the overall efficiency of the system. Understanding of this effect requires further research, and shall help to employ the most successful means of using solar concentrators. This study reviews the causes and effects of the non-uniformity in the CPV systems. It highlights the importance of this issue in solar cell design and reviews the methods for the solar cell characterization under non-uniform flux conditions. Finally, it puts forward a few methods of improving the CPV performance by reducing the non-uniformity effect on the concentrator solar cells. © 2012 Elsevier Ltd.

A Cole, I Baistow, L Brown, S Devenport, K Drew, KC Heasman, D Morrison, TM Bruton, L Serenelli, S De Iuliis, M Izzi, M Tucci, E Salza, L Pirozzi (2011)Silicon Based Photovoltaic Cells For Concentration - Research And Development Progress In Laser Grooved Buried Contact Cell Technology, In: 7TH INTERNATIONAL CONFERENCE ON CONCENTRATING PHOTOVOLTAIC SYSTEMS (CPV-7)1407 AMER INST PHYSICS
KC HEASMAN, AR ADAMS, RG PLUMB (1987)SCANNING THE LASER GAIN SPECTRUM USING DISTRIBUTED FEEDBACK AND HYDROSTATIC-PRESSURE, In: ELECTRONICS LETTERS23(11)pp. 555-557 IEE-INST ELEC ENG
Jérémy Barbé, Declan Hughes, Zhengfei Wei, Adam Pockett, Harrison K. H. Lee, Keith C. Heasman, Matthew J. Carnie, Trystan M. Watson, Wing C. Tsoi (2019)Radiation Hardness of Perovskite Solar Cells Based on Aluminum-Doped Zinc Oxide Electrode Under Proton Irradiation, In: Solar RRL3(12)1900219 Wiley

Perovskite solar cells (PSCs) have gained increasing interest for space applications. However, before they can be deployed into space, their resistance to ionizing radiations, such as high‐energy protons, must be demonstrated. Herein, the effect of 150 keV protons on the performance of PSCs based on aluminum‐doped zinc oxide (AZO) transparent conducting oxide (TCO) is investigated. A record power conversion efficiency of 15% and 13.6% is obtained for cells based on AZO under AM1.5G and AM0 illumination, respectively. It is demonstrated that PSCs can withstand proton irradiation up to 10¹³ protons cm⁻² without significant loss in efficiency. From 10¹⁴ protons cm⁻², a decrease in short‐circuit current of PSCs is observed, which is consistent with interfacial degradation due to deterioration of the Spiro‐OMeTAD holes transport layer during proton irradiation. The structural and optical properties of perovskite remain intact up to high fluence levels. Although shallow trap states are induced by proton irradiation in perovskite bulk at low fluence levels, charges are released efficiently and are not detrimental to the cell's performance. This work highlights the potential of PSCs based on AZO TCO to be used for space applications and gives a deeper understanding of interfacial degradation due to proton irradiation.

KC Heasman, TM Bruton, A Cole, LM Brown, K Drew (2011)Design considerations for silicon solar cells as part of the ASPIS concentrator concept, In: Proceedings 26th European PV Solar Energy Conferencepp. 625-628
KC Heasman, LM Brown, O Tari, F Roca, L Lancellotti (2011)Design strategies for solar cells devised to the low wavelength portion of the solar spectrum, In: Proceedings 26th European PV Solar Energy Conferencepp. 1459-1462
KC Heasman, M Nrton, GE Georghiou, V Guidi, D Vincenzi, L Trovato, M Luisa, F Aleo, C Olson, M Wild-Scholten, E Medina, A Samo, C Cancro, G Graditi, F Roca, T Aitasalo, R Kenny, S Borschchov, S Padovani, M Noack, P Zurro, A Antonini, MA Butturi, M Sturm, B Schineller, N Gogogneau, G Beaudoin, R Jakomin, I Sagnes, C Chernelli, A Martinelli, P Morabito, A Minuto, G Timo (2011)Optimization of point focus and mirror based spectra splitting CPV systems: Results from the APOLLON project, In: Proceedings 26th European Photovoltaic Solar Energy Conference and Exhibitionpp. 137-144
KC Heasman, M Lesniak, BM Neville, AE Hughes, DW Cunningham, AM Mitchell, BE Ford, JG Summers, TM Bruton (1991)Factors Influencing the Minority Carrier Diffusion Length in Multicrystalline Silicon Produced in a HEM Furnace, In: Photovoltaic Specialists Conference, 1991., Conference Record of the Twenty Second IEEEpp. 1010-1014
KC Heasman, I Baistow, A Cole, D Tregurtha, L Brown, TM Bruton, S Roberts, S Devenport (2009)PROCESS DEVELOPMENT OF SHAPE AND COLOUR IN LGBC SOLAR CELLS FOR BIPV APPLICATIONS
KC Heasman, TM Bruton, M Brown, A Cole, S Roberts (2007)PROCESS DEVELOPMENT OF COLOURED LGBC SOLAR CELLS FOR BIPV APPLICATIONS, In: Proceedings 22nd European PV Solar Energy conference
KC Heasman, MP Lesniak, BM Neville, AE Hughes (1991)Laser Scanning Analysis of Silicon Solar Cells, In: Proceedings of the International Conference, held at Lisbon, Portugal, 8–12 April 1991pp. 644-646
KC Heasman, RDW Scott, R Russell, TM Bruton, NB Mason (1996)The Development of Coloured Silicon Solar Cells for Architectural Applications, In: Proceedings EuroSun’96
KC Heasman, EP O'Reilly, GP Witchlow, W Batty, AR Adams (1987)Proposal For A Low Threshold Current Long Wavelength Strained Layer Laser, In: Novel Optoelectronic Devices
KC Heasman, B Garrard, K Webster, I Baistow, A Cole, L Brown, TM Bruton, S Roberts, S Devenport (2009)A SUMMARY OF THE HAVEMOR PROJECT - PROCESS DEVELOPMENT OF SHAPED AND COLOURED SOLAR CELLS FOR BIPV APPLICATIONS, In: Proc.24th European PV Solar Energy Conferencepp. 4276-4279
KC Heasman, TM Bruton, I Baistow, S Devenport, S Roberts, M Brown, A Cole (2011)PROCESS DEVELOPMENT OF LASER GROOVED BURIED CONTACT SOLAR CELLS FOR USE AT CONCENTRATION FACTORS UP TO 100X, In: Proceedings 22nd European PV Solar Energy
KC Heasman, EP O'Reilly, AR Adams (1989)Characterization and Design of Semiconductor Lasers Using Strain, In: NATO ASI Series189pp. 279-301 Springer New York
KC Heasman, EP O'reilly, W Batty, A Ghiti (1988)Long wavelength strained layer lasers, In: IEE Colloquium on `Heterojunction and Quantym Well Devices: Physics, Engineering and Applicationspp. 3/1-3/3
KC Heasman, NB Mason, S Roberts, TM Bruton (2005)Low cost, 100X point focus silicon concentrator cells made by the LGBGpp. 647-650
KC Heasman, CM Ramsdale, J Sherborne, TM Bruton (2002)Concepts For The Manufacture Of Silicon Solar Cells Modules For Use In Concentrating Systems Up To 5X, In: Proceedings 29th IEEE PVSEC Conference
KC Heasman, MA Balbuena, R Russell, NB Mason, DW Cunningham, JP Nagle, TM Bruton (1997)Large Area High Efficiency Silicon Solar Cells made by the Laser Grooved Buried Grid Processpp. 761-762
AR Adams, KC Heasman, J Hilton (1987)A reassessment of intervalence band absorption in 1.6μm (GaIn)(AsP)/InP, In: Semiconductor Science and Technology2(12)pp. 761-764

In the paper the authors re-evaluate the influence of intervalence band absorption on the temperature sensitivity of 1.6 mu m (GaIn)(AsP)/InP lasers and emphasise its general importance in semiconductor lasers operating at several times their threshold current.

KC Heasman (1998)480 kWpeak EUCLIDES Concentrator Power Plant Using Parabolic Troughs, In: Proceedings 2nd World PV Solar Energy Conferencepp. 1449-1452
KC Heasman, G Timo, M Noack, MA Butturi, M Sturm, M Wild-Scholten (2010)ENVIRONMENTAL SUSTAINABILITY OF CONCENTRATOR PV SYSTEMS: PRELIMINARY LCA RESULTS OF THE APOLLON PROJECT, In: Proceedings 25th European PV Solar Energy Conference
KC Heasman, R Russell, TM Burton, B Norton, T Hyde, D McLarnon, A Zacharopoulos, PC Eames (2000)The Experimental Fabrication and Characterisation of a Low Cost High Efficiency Photovoltaic Concentrator Panel Suitable for Building Integration, In: Proceedings 16th European PV Solar Energy Conference
KC Heasman, T Bruton, A Cole, LM Brown, K Drew (2009)FRONT DICING TECHNIQUE FOR PRE-ISOLATION OF CONCENTRATOR SILICON SOLAR CELLS, In: Proceedings 25th European PV Solar Energy Conferencepp. 941-945
KC Heasman, R Russell, TM Bruton, NB Mason (1995)Optimisation of Low-Cost Concentrator Solar Cells, In: Proceedings 13th European PV Solar Energy Conferencepp. 23-27
KC HEASMAN, AR ADAMS, PD GREENE, GD HENSHALL (1987)PRESSURE-DEPENDENCE OF THRESHOLD CURRENT AND CARRIER LIFETIME IN 1.55-MU-M GAINASP LASERS, In: ELECTRONICS LETTERS23(10)pp. 492-493 IEE-INST ELEC ENG
KC Heasman, R Russell, TM Bruton, B Norton, PC Eames, A Zacharopoulos (2000)A Detailed Optical and Thermal Analysis of a Design for a Low Cost High Efficiency Photovoltaic Concentrator Panel Suitable for Building Integration, In: Proceedings 16th European PV Solar Energy Conference
KC HEASMAN, J HAYES, AR ADAMS, PD GREENE (1981)TEMPERATURE-DEPENDENCE OF THE TRANSFERRED ELECTRON THRESHOLD CURRENTIN IN1-XGAXASYP1-Y, In: ELECTRONICS LETTERS17(20)pp. 756-757 IEE-INST ELEC ENG
YS TANG, KC HEASMAN, WP GILLIN, BJ SEALY (1989)CHARACTERISTICS OF RARE-EARTH ELEMENT ERBIUM IMPLANTED IN SILICON, In: APPLIED PHYSICS LETTERS55(5)pp. 432-433 AMER INST PHYSICS
KC Heasman, F Roca, L Serenelli, TM Bruton, D Morrison, K Drew, S Devenport, A Cole, LM Brown (2011)20% laser grooved buried contact Cz silicon solar cells for the APOLLON project, In: Proceedings 26th European PV Solar Energy Conference
KC HEASMAN, P BLOOD, AR ADAMS, ED FLETCHER (1987)PRESSURE-DEPENDENCE OF THE NONRADIATIVE LIFETIME IN GAAS/AIGAAS DOUBLE-HETEROSTRUCTURE LASERS, In: JOURNAL OF APPLIED PHYSICS62(8)pp. 3448-3450 AMER INST PHYSICS
KC Heasman, R Russell, TM Bruton, B Norton, D McLarnon, A Zacharopoulos, PC Eames (1998)Low Cost Facade Integrated Concentrator Photovoltaics, In: Proceedings 2nd World PV Solar Energy Conferencepp. 1449-1452
EP OREILLY, KC HEASMAN, AR ADAMS, GP WITCHLOW (1987)CALCULATIONS OF THE THRESHOLD CURRENT AND TEMPERATURE SENSITIVITY OF A (GAIN)AS STRAINED QUANTUM-WELL LASER OPERATING AT 1.55 MU-M, In: SUPERLATTICES AND MICROSTRUCTURES3(2)pp. 99-102 ACADEMIC PRESS LTD