City University of Hong Kong

Kin Man Yu (余健文), Ph. D.

Professor

 

Contact Information:

Department of Physics and Materials Science,
City University of Hong Kong
83 Tat Chee Avenue,
Hong Kong SAR, China.
Room G6758, Lift 2
Tel:  34427813
Fax: 34420539
Email: kinmanyu@cityu.edu.hk

 

Profile:

Professor Kin Man Yu grew up in Hong Kong and graduated from Saint Joseph’s College, Hong Kong in the late 1970s.  He received his B.S. in Engineering Physics in 1982 and Ph. D. in Materials Science and Mineral Engineering in 1987, both from the University of California, Berkeley.

From 1987-2014, Dr. Yu was Staff Scientist and Principal Investigator in the Materials Sciences Division at the Lawrence Berkeley National Laboratory.  He was also the director of the Ion Beam Analysis Facility, managing a state-of-the-art ion beam laboratory preforming a wide spectrum of material analysis techniques.  At LBNL Dr. Yu co-led the Solar Energy Materials Research Group and conducted fundamental research on photovoltaic materials.  Dr. Yu has an h-index of 47 (51 in google scholar).  He has coauthored 12 book chapters and invited reviews, published over 400 journal articles with over 10000 citations, and co-authored several patents related to advanced PV technology.  In 2006, Dr. Yu received an R&D 100 award (Editor’s choice for most promising technology) for his work with Dr. Wladek Walukiewicz on multiband semiconductors for high efficiency solar cells.  Since August 2014, he serves as an Associate Editor for the Journal of Applied Physics.

Dr, Yu joined the City University of Hong Kong as a professor in the Department of Physics and Materials Science in October 2014.

Research Interests:

Professor Yu’s current research interests include:

§  Structural, optical and electronic properties of thin film semiconductors

§  Design, synthesis and characterization of group III nitrides

§  Development of novel highly mismatched III-V and II-V semiconductor alloys for full spectrum photovoltaic applications

§  Transparent conductors for high efficiency PV applications

§  Defects in semiconductors

§  Ion beam analysis and modification of materials

Research Openings Available (Post-docs, research assistants, graduate students):

A number of openings are available for highly motivated individuals with interests in the field of semiconductor physics and photovoltaic materials.

Interested applicants should send their CV via emails to <kinmanyu@cityu.edu.hk>

Information for graduate studies can be found at http://www.sgs.cityu.edu.hk/prospective/rpg.

Publications:

I.                 Book Chapters and Invited Reviews

1.     Peter R. Stone, Oscar D. Dubon, Michael A. Scarpulla, and Kin M. Yu, “Ga1-xMnxP Syntheisized by Ion Implantation and Pulsed Laser Melting,” in Handbook of Spintronic Semiconductors, eds. Weimin M. Chen and Irinda A. Buyanova (Pan Stanford Publishing Pte. Ltd, Singapore, 2010) Chapter 5, p. 157-180.

2.     K. Alberi, K. M. Yu and W.Walukiewicz, “Electronic Structure of Mn in III-Mn-V Ferromagnetic Semiconductors,” in Handbook of Spintronic Semiconductors, eds. Weimin M. Chen and Irinda A. Buyanova (Pan Stanford Publishing Pte. Ltd, Singapore, 2010) Chapter 4, p. 123-156.

3.     W. Walukiewicz, K. M. Yu, J. W. Ager III,  R. E. Jones, and N. Miller, “Electronic Properties of InN and InGaN: Defects and Doping,” in Indium Nitride and Related Alloys, eds. T. D. Veal, C. F. McConville, and W. J. Schaff (CRC Press, Boca Raton, Fl, 2010) Chapter 10.

4.     K. M. Yu, T. Wojtowicz, W.Walukiewicz, X. Liu, and J. K. Furdyna, “Fermi level effects on Mn incorporation in III-Mn-V ferromagnetic semiconductors,” Semiconductors and Semimetals, Volume 82, Spintronics, Edited By Tomasz Dietl, David Awschalom, Maria Kaminska, Hideo Ohnn, Chapter 3, Pages 89-133 (Elsevier 2008).

5.     W. Walukiewicz, K. Alberi, J. Wu, W. Shan, K. M. Yu, and J. W. Ager III, “Electronic Band Structure of Highly Mismatched Semiconductor Alloys,” in Physics Dilute III-V Nitride Semiconductors and Material Systems: Physics and Technology, edited by Ayse Erol (Springer-Verlag Berlin-Heidelberg 2008) Chapter 3.

6.     K. M. Yu, M. A. Scarpulla, W. Shan, J. Wu, J. W. Beeman, J. B. Jasinski, Z. Liliental-Weber, O. D. Dubon, and W. Walukiewicz, “Energetic Beam Synthesis of Dilute Nitrides and Related Alloys,” in Dilute III-V Nitride Semiconductors and Material Systems: Physics and Technology, edited by Ayse Erol (Springer-Verlag Berlin-Heidelberg 2008) Chapter 1

7.     W. Walukiewicz, J. W. Ager III, K. M. Yu, Z. Liliental-Weber, J. Wu, S. X. Li, R. E. Jones, and J. D. Denlinger, “Structure and Electronic Properties of InN and In-rich Group III-Nitride Alloys,” J. Physics D 39, R85 (2006).

8.     W. Shan, W. Walukiewicz, K.M. Yu, J. Wu, J.W. Ager III, and E.E. Haller, “New Development in Dilute Nitride Materials Resaerch,” in III-Nitride Semiconductor Materials, edited by Zhe Chuan Feng (World Scientific, Singapore, 2006). Chapter 12.

9.     W. Walukiewicz, W. Shan, J. Wu, K. M. Yu, and J. W. Ager III, “Band Anticrossing and Related Electronic Structure in III-N-V Alloys,” in Dilute Nitride Semiconductors, edited by M. Henini (Elsevier, Oxford, UK, 2005) Chapter 10, p. 325-392.

10.  W. Shan, K. M. Yu, W. Walukiewicz, J. Wu, J.W. Ager III, and E.E. Haller, “Band Anticrossing in Dilute Nitrides,” J. Phys. 16, S3355 (2004).

11.  W. Walukiewicz, W. Shan, J. Wu, and K. M. Yu, “Band Anticrossing in III-N-V Alloys: Theory and Experiments,” in Physics and Applications of Dilute Nitrides, edited by Irina Buyanova and Weimin Chen (Taylor & Francis, New York, 2004) Chapter 2, p. 23-64.

12.  K. M. Yu, “Ion Beam Synthesis and n-type Doping of Group III-Nx-V1-x Alloys,” Semicond. Sci. Technol. 17, 785 (2002).

II.               Selected Refereed Journal Articles (since 2000)

1.     K. M. Yu, S. V. Novikov, Min Ting, W. L. Sarney, S.P. Svensson, M. Shaw, R. W. Martin, W.Walukiewicz, and C. T. Foxon, “Growth and Characterization of Highly Mismatched GaN1-xSbx Alloys,” J. Appl. Phys. 116, 123704 (2014).

2.     Junichi Nishitani, Douglas Detert, Jeffrey Beeman, Kin Man Yu, and Wladek Walukiewicz, “Surface Hole Accumulation and Fermi level stabilization energy in SnTe,” Appl. Phys. Express 7, 091201 (2014).

3.     D. M. Detert, K. Tom, C. Battaglia, J. Denlinger, S. H. M. Lim, A. Javey, A. Anders, O. D. Dubon, K. M. Yu, and W. Walukiewicz, “Fermi level stabilization and band edge energies in CdxZn1-xO Alloys,” J. Appl. Phys. 115, 233708 (2014).

4.     Tooru Tanaka, Masaki Miyabara, Yasuhiro Nagao, Katsuhiko Saito, Qixin Guo, Mitsuhiro Nishio, Kin M. Yu, Wladek Walukiewicz, “Photogenerated current by two-step photon excitation in ZnTeO Intermediate Band Solar Cells,” IEEE J. Photovoltaics 4 (1), 196 (2014).

5.     Douglas M. Detert, Sunnie H.M. Lim, Kyle Tom, Alexander V. Luce, André Anders, Oscar D. Dubon, Kin Man Yu, Wladek Walukiewicz, “Crystal Structure and Properties of CdxZn1-xO Alloys Across the Full Composition Range,” Appl. Phys. Lett., 102, 232103 (2013).

6.     Y. J. Kuang (邝彦瑾), K. M. Yu, R. Kudrawiec, A. V. Luce, M. Ding, W. Walukiewicz, and C. W. Tu, “GaNAsP: an intermediate band semiconductor grown by gas-source molecular beam epitaxy,” Appl. Phys. Lett. 102 112105 (2013).

7.     K. M. Yu, W.L. Sarney, S. V. Novikov, D. Detert, R. Zhao, J. Denlinger, S.P. Svensson, O. D. Dubon, W.Walukiewicz, and C. T. Foxon, “Highly Mismatched N-rich GaN1-xSbx films grown by Low Temperature Molecular Beam Epitaxy,” Appl. Phys. Lett. 102, 102104 (2013).

8.     Marie A. Mayer, Derrick T. Speaks, Jonathan D. Denlinger, Lothar Reichertz, Jeff Beeman, Kin Man Yu, Eugene E. Haller, and Wladek Walukiewicz, “ZnO1-xSex as a photoelectrochemical anodic absorber,” J. Phys. Chem. C116, 15281 (2012).

9.     Kin Man Yu, Marie A. Mayer, Derrick T. Speaks, Hongcai He, Ruying Zhao, L. Hsu, Samuel S. Mao, E. E. Haller, and Wladek Walukiewicz, “Ideal Transparent Conductors for Full Spectrum Photovoltaics,” J. Appl. Phys. 111, 123505 (2012).

10.  M. Dobrowolska,  K. Tivakornasithorn, X. Liu, J. K. Furdyna, M. Berciu, K. M. Yu and W. Walukiewicz, “Controlling Curie temperature in (GaMn)As through location of the Fermi level within the impurity band,” Nature Materials 11, 444–449 (2012).

11.  X. Levander, S. V. Novikov, Z. Liliental-Weber, R. dos Reis, J. D. Denlinger, J. Wu, O. D. Dubon, C. T. Foxon, K. M. Yu, and W.Walukiewicz, “Growth and Transport Properties of p-type GaNBi Alloys,” Invited feature article, J. Mater. Res. 26, pp 2887-2894 (2011).

12.  Nair. López, Lothar. A. Reichertz, K. M. Yu, Kenneth Campman, and Wladek. Walukiewicz, “Engineering the Electronic Band Structure for Multiband Solar Cells,” Phys. Rev. Lett. 106, 028701 (2011).

13.  T. Tanaka, K. M. Yu, A. X. Levander, O. D. Dubon, L. A. Reichertz, N. Lopez, M. Nishio, W. Walukiewicz, “Demonstration of ZnTe1-xOx intermediate band solar cell,” Jpn. J. Appl. Phys. 50, 082304 (2011).

14.  K. Wang, N. Miller, R. Iwamoto, T. Yamaguchi, M. Mayer, T. Araki, Y. Nanishi, J. W Ager III, K. M. Yu, and W. Walukiewicz, “Mg doped InN and confirmation of free holes in InN,” Appl. Phys. Lett. 98, 042104 (2011).

15.  Marie A. Mayer, Derrick T. M Speaks, Kin Man Yu, Samuel S. Mao, Eugene E. Haller, and Wladek Walukiewicz, “Band structure engineering of ZnO1-xSex alloys,” Appl. Phys. Lett. 97, 022104 (2010).

16.  X. Levander, K. M. Yu, S. Novikov, A. Tseng, W. Walukiewicz, C. T. Foxon, O. D. Dubon, J. Wu, “GaN1-xBix: Extremely Mismatched Semiconductor Alloys,” Appl. Phys. Lett. 97, 141919 (2010).

17.  D. T. M. Speaks, K. M. Yu, S. S. Mao, E. E. Haller and W. Walukiewicz, “Fermi Level Stabilization Energy in Cadmium Oxide,” J. Appl. Phys. 107, 113706 (2010).

18.  M. A. Mayer, P. R. Stone, N. Miller, H. M. Smith III, O.D. Dubon, E. E. Haller, K. M. Yu, W. Walukiewicz, X. Liu and J.K. Furdyna, “Electronic structure of Ga1−xMnxAs analyzed according to hole-concentration-dependent measurements,” Phys. Rev. B81, 045205 (2010).

19.  André Anders, Sunnie H.N. Lim, Kin Man Yu, Joakim Andersson, Johanna Rosén, Mike McFarland, Jeff Brown, “High quality ZnO:Al transparent conducting oxide films synthesized by pulsed filtered cathodic arc deposition,” Thin Solid Films 518, 3313 (2010).

20.  K. M. Yu, S. V. Novikov, R. Broesler, I. N. Demchenko, J. D. Denlinger, Z. Liliental-Weber, F. Luckert, R. W. Martin, W. Walukiewicz, and C. T. Foxon, “Highly Mismatched GaN1-xAsx Alloys in the Whole Composition Range,” J. Appl. Phys. 106, 103709 (2009).

21.  K. M. Yu, “N-type Doping of InGaN by High Energy Particle Irradiation,” Phys. Status Solidi A 206, No. 6, 1168–1175 (2009).

22.  K. Alberi, K. M. Yu, P.R. Stone, O.D. Dubon, W. Walukiewicz, X. Liu, and J. K. Furdyna, “The formation of a Mn-derived impurity band in III-Mn-V alloys by valence band anticrossing,” Phys. Rev. B78, 075201 (2008).

23.  K. Alberi, W. Walukiewicz, K. M. Yu, O.D. Dubon, K. Bertulis, A. Krotkus, “Valence Band Anticrossing in GaBixAs1-x,” Appl. Phys. Lett., 91, 051909 (2007).

24.  K. Alberi, J. Wu, W. Walukiewicz, K. M. Yu, O.D. Dubon, S.P. Watkins, C.X. Wang,  X. Liu, Y.-J. Cho, and J. Furdyna, “Valence Band Anticrossing in Mismatched III-V Semiconductor Alloys,” Phys. Rev. B 75, 045203 (2007).

25.  R.E. Jones, K. M. Yu, S. X. Li, W. Walukiewicz, J. W. Ager III, E. E. Haller, H. Lu, and W.J. Schaff, “Evidence for p-type doping of InN,” Phys. Rev. Lett. 96, 125505 (2006).

26.  K. M. Yu, W. Walukiewicz, J.W. Ager III, D. Bour, R. Farshchi, O. D. Dubon, S. X. Li, I. D. Sharp, and E. E. Haller, "Multiband GaNAsP Quaternary Alloys," Appl. Phys. Lett. 88, 092110 (2006).

27.  S. X. Li, R. E. Jones, E. E. Haller, K. M. Yu, W. Walukiewicz, J. W. Ager III, and Z. Liliental-Weber, Hai Lu and William J. Schaff, “Photoluminescent Properties of Energetic Particle-Irradiated InxGa1-xN Alloys,” Appl. Phys. Lett. 88, 151101 (2006).

28.  S. X. Li, K. M. Yu, R. E. Jones, J. Wu, W. Walukiewicz, J. W. Ager III, W. Shan, E. E. Haller, Hai Lu, and William J. Schaff, “Fermi level stabilization energy in group III-nitrides,” Phys. Rev. B71, 1612(R) (2005).

29.  J. Wu, W. Walukiewicz, K. M. Yu, J. D. Denlinger, W. Shan, J. W. Ager III, E. E. Haller, and T. F. Kuech; “Valence Band Hybridization in N-rich GaN1-xAsx Alloys,” Phys. Rev. B 70, 115214 (2004).

30.  K. M. Yu, W. Walukiewicz, J. Wu, W. Shan, and J. W. Beeman, M. A. Scarpulla, O. D. Dubon, and P. Becla, “Synthesis and Optical Properties of II-O-VI Highly Mismatched Alloys,” J. Appl. Phys.95, 6232 (2004).

31.  J. Wu, K. M. Yu, W. Walukiewicz, G. He, E. E. Haller, D. E. Mars, D. R Chamberlin, “Mutual Passivation Effects in Si-doped Dilute InyGa1-yAs1-xNx Alloys,” Phys. Rev. B 68, 195202 (2003).

32.  K. M. Yu, W. Walukiewicz, J. Wu, W. Shan, and J. W. Beeman, M. A. Scarpulla, O. D. Dubon, and P. Becla, "Diluted II-VI Oxide Semiconductors with Multiple Band Gaps," Phys. Rev. Lett. 91, 246203 (2003).

33.  J. Wu, W. Walukiewicz, K.M. Yu, W. Shan, J.W. Ager III, E.E. Haller, Hai Lu, and William J. Schaff, W. K. Metzger, Sarah R. Kurtz, and J. F. Geisz, “Superior Radiation Resistance of In1-xGaxN Alloys: a Full-Solar-Spectrum Photovoltaic Material System,” J. Appl. Phys. 94, 6477 (2003).

34.  K. M. Yu, W. Walukiewicz, M. A. Scarpulla, O. D. Dubon, J. Jasinski, Z. Liliental-Weber, J. Wu, J. W. Beeman, M. R. Pillai, and M. J. Aziz, “Synthesis of GaNxAs1-x Thin Films by Pulsed Laser Melting and Rapid Thermal Annealing (PLM-RTA) of N+-implanted GaAs,” J. Appl. Phys. 94, 1043 (2003).

35.  K. M. Yu, W. Walukiewicz, J. W. Beeman, M. A. Scarpulla, O. Dubon, M. R. Pillai, and M. Aziz, “Enhanced Nitrogen Incorporation by Pulsed Laser Annealing of GaNxAs1-x Formed by N Implantation,” Appl. Phys. Lett. 80, 3958 (2002).

36.  K. M. Yu, W. Walukiewicz, J. Wu, D. Mars, D. R Chamberlin M. A. Scarpulla, O. D. Dubon, and J. F. Geisz, , "Mutual Passivation of Electrically Active and Isovalent Impurities," Nature Materials 1, 185 (2002).

37.  K. M. Yu, W. Walukiewicz, T. Wojtowicz, I. Kuryliszyn, X. Liu, Y. Sasaki, and J.K. Furdyna, "Effect of the location of Mn sites in ferromagnetic Ga1-xMnxAs on its Curie temperature," Phys. Rev. B65, 201303(R) (2002).

38.  J. Wu, W. Walukiewicz, K. M. Yu, J. W. Ager III, E. E. Haller, Hai Lu, William J. Schaff, and Y. Nanishi, “Unusual properties of the fundamental band gap of InN,” Appl. Phys. Lett. 80, 3967 (2002).

39.  C. J. Glover, M. C. Ridgway, K. M. Yu, G. J. Foran, D. Desnica-Frankovic, C. Clerc, J. L. Hansen, and A. Nylandsted Larsen, “Structural-Relaxation-Induced Bond-length and Bond-angle Changes in Amorphised Ge,” Phys. Rev. B63, 073204 (2001).

40.  K. M. Yu, W. Walukiewicz, J. Wu, J. W. Beeman, J. W. Ager III, E. E. Haller, W. Shan, H. P. Xin, C. W. Tu, and M. C. Ridgway, “Formation of Diluted III-V Nitrides by N Ion Implantation," J. Appl. Phys. 90, 2227 (2001)

41.  W. Walukiewicz, W. Shan, K. M. Yu, J. W. Ager III, E. E. Haller, I. Miotlowski, M. J. Seong, H. Alawadhi, and A. K. Ramdas, “ Interaction of Localized Electronic States with the Conduction Band: Band Anticrossing in II-VI Semiconductor Ternaries,” Phys. Rev. Lett. 85, 1552 (2000).

42.  K. M. Yu, W. Walukiewicz, W. Shan, J. W. Ager III, J. Wu, E. E. Haller, J. F. Geisz, D. J. Friedman, J. M. Olson, and Sarah R. Kurtz, “Nitrogen-Induced Enhancement of the Maximum Electron Concentration in Group III-N-V Alloys,” Phys. Rev. B61, R13337 (2000).

III.             Patents

1.        W. Walukiewicz and K. M.  Yu, “Co-implantation of group VI elements and N for formation of non-alloyed ohmic contacts for n-type semiconductors,” United States Patent #6,759,312, July 6, 2004.

2.        W. Walukiewicz , K. M. Yu, J. Wu, and William J Schaff, “Broad Spectrum Solar Cell,” United States Patent #7,217,882, May 15, 2007.

3.        Wladyslaw Walukiewicz, Kin Man Yu, and Junqiao Wu, “Multiband semiconductor compositions for photovoltaic devices,” United States Patent #7,709,728, May 4, 2010.

4.        W. Walukiewicz, J.W. Ager, K.M. Yu, “Low-resistance Tunnel Junctions for High Efficiency Tandem Solar Cells.” Patent Application No. PCT/US2008/004572.

5.        W. Walukiewicz, J.W. Ager III, K.M. Yu, “Single p-n Junction Tandem Photovoltaic Device.” U.S. Patent #8,039,740, October 18, 2011.

6.        W. Walukiewicz, J.W. Ager III, K.M. Yu, “Group III-Nitride Solar Cell with Grade Compositions.” Patent Application No. 61/019,536.

7.        W. Waluliewicz, K. M. Yu, “Dilute Group III-V Nitride Intermediate Band Solar Cells with Contact Blocking Layers”, U.S. Patent Application Serial No. 12/558,446, submitted 9/11/09.

8.        Kin Man Yu, W. Walukiewicicz, A. X. Levander, S. V. Novikov, C. T. Foxon, “P-type amorphous GaNAs alloys as low resistance ohmic contact to p-type group III-Nitride semiconductors,” U.S. Patent Application Ser. No:61/488,036, filed May 19, 2011 (LBNL Docket: JIB-3022P.)

9.        W. Walukiewicz, K.M. Yu, and Junqiao Wu, “Multiband semiconductor compositions for photovoltaic devices,” U.S. Patent No. 8,129,615, March 6, 2012.

10.    W. Walukiewicz, K.M. Yu, “Compositionally Graded Dilute Group III-V Nitride Cell With Blocking Layers For Multijunction Solar Cell,” pub. # WO/2013/043875, pub date March 28, 2013.