List of my work

List of my published work

1) J.H.Kim, H.Asahi, K.Asami, K.Iwata, S.G.Kim, S.Gonda: "Growth temperature dependence of optical properties of gas source MBE grown GaP/AlP short period superlattices."
Appl. Surf. Sci. 82/83 (1994) 76-79
2) K.Iwata, H.Asahi, J.H.Kim, X.F.Liu, S.Gonda, Y.Kawaguchi, T.Matsuoka: "Gas source MBE growth of InAlP band offset reduction layer on p-type ZnSe."
J. Crystal Growth, 150 (1995) pp.833-837.
3) J.H.Kim, H.Asahi, K.Asami, K.Iwata, S.G.Kim, T.Ogura, S.Gonda: "Gas source MBE growth of GaP/AlP modulated superlattices and their optical properties."
J. Crystal Growth, 150 (1995) pp.574-578.
4) K.Iwata, H.Asahi, T.Ogura, J.Sumino, S.Gonda, A.Ohki, Y.Kawaguchi and T.Matsuoka: "Low temperature grown Be-doped InAlP band offset reduction layer to p-type ZnSe."
Journal of Electronic Materials, 25 (1996) pp.637-641.
5) K.Iwata, H.Asahi, S.J.Yu, K.Asami, H.Fujita, M.Fushida and S.Gonda: "High Quality GaN Growth on (0001) Sapphire by Ion-Removed Electron Cyclotron Resonance Molecular Beam Epitaxy and First Observation of (2x2) and (4x4) Reflection High Energy Diffraction Patterns."
Jpn.J.Appl.Phys., 35 (1996) pp.L289-L292.
6) H.Asahi, K.Yamamoto, K.Iwata, S.Gonda and K.Oe: "New III-V Compound Semiconductors TlInGaP for 0.9μm to over 10μm Wavelength Range Laser Diodes and Their First Successful Growth."
Jpn.J.Appl.Phys., 35 (1996) pp.L876-L879.
7) K.Iwata, H.Asahi, K.Asami and S.Gonda: "Gas source Molecular Beam Epitaxy growth of GaN1-xPx(x<0.015) using Ion-Removed Electron Cyclotron Resonance radical cell."
Jpn.J.Appl.Phys., 35 (1996) pp.L1634-L1637.
8) R.Kuroiwa, H.Asahi,K.Iwata, S.J.Kim, J.H.Noh, K.Asami and S.Gonda: "Gas Source Molecular Beam Epitaxy growth of GaN-Rich Side of GaNP Alloy and Their Observation by Scanning Tunneling Microscopy."
Jpn.J.Appl.Phys., 36 (1996) pp.L3810-L3813.
9) K.Iwata, H.Asahi, K.Asami and S.Gonda: "Gas source Molecular Beam Epitaxy growth of GaN rich side of GaN1-xPx using Ion-Removed Electron Cyclotron Resonance radical cell."
J. Crystal Growth, 175 (1997) pp.150-155.
10) H.Asahi, K.Yamamoto,K.Iwata S.Gonda and K.Oe: "New semiconductors TlInGaP and Their gas source MBE growth."
J. Crystal Growth, 175 (1997) pp.1195-1199.
11) K.Yamamoto, H.Asahi, M.Fushida,K.Iwata and S.Gonda: "Gas source Molecular Beam Epitaxy growth of TlInP new infrared optical devices."
Journal of Applied Physics, 81 (1997) pp.1704-1707.
12) K.Iwata, H.Asahi, K.Asami and S.Gonda: "Gas Source Molecular Beam Epitaxy Growth of GaN on C-,A-,R-,M-plane Sapphire and Silica Glass Substrate."
Jpn.J.Appl.Phys., 36 (1997) pp.L661-L664.
13) S.Gonda, H.Asahi,K.Iwata and K.Asami: "GaN and related nitrides by gas source MBE using ion-removed radical cell."
J. Korean Phys. Soc., 30 (1997) pp.S21-S25.
14) S.J.Yu, H.Asahi,K.Iwata, R.Kuroiwa, J.H.Noh, K.Asami, S.Gonda: "Ion-removed ECR-MBE growth of InGaN on (0001) Al2O3."
J. Korean Phys. Soc., 30 (1997) pp.S127-S130.
15) K.Iwata, H. Asahi, K. Asami, R. Kuroiwa and S. Gonda: "Strong photoluminescence emission from GaN grown on amorphous silica substrates by gas source MBE."
J. Crystal Growth, 188 (1998) pp.98-102.
16) K.Iwata, H. Asahi, K. Asami, R. Kuroiwa and S. Gonda: "GaN-rich side of GaNAs grown by gas source MBE."
Jpn.J.Appl.Phys., 37(3B) (1998) pp.1436-1439.
17) K.Iwata, H. Asahi, K. Asami, R. Kuroiwa, H. Tampo and S. Gonda: "Promising characteristics of GaN grown on amorphous silica substrates by gas source MBE."
J. Crystal Growth, 189 (1998) pp.218-222.
18) R. Kuroiwa, H. Asahi, K. Asami, S.J.Kim, K.Iwata and S. Gonda: "Optical properties of GaN-rich side of GaNP and GaNAs alloys grown by gas source MBE."
Applied Physics Letters, 73 (1998) pp.2630-2632.
19) H. Asahi, K.Iwata, H. Tampo, R. Kuroiwa, M.Hiroki, K. Asami, S.Nakamura and S. Gonda: "Very strong photoluminescence emission from GaN grown on amorphous silica substrate by gas source MBE."
J. Crystal Growth, 201/202 (1999) pp.371-375.
20) P.Fons, K.Iwata,S.Niki, A.Yamada and K.Matsubara: "Growth of high-quality epitaxial ZnO films on alpha-Al_2O_3."
J. Crystal Growth, 201/202 (1999) pp.627-632.
21) S.Niki, P.Fons, Y.Lacroix, K.Iwata, A.Yamada,h.ohyanagi, M.Uchino, R.Suzuki, A.Ishibashi, S.Ohira, N.Sakai and H.Yokokawa: "Control of intrinsic in molecular beam epitaxy grown CuInSe_2."
J. Crystal Growth, 201 (1999) p.1061.
22) K.Matsubara, S.Niki, M. Watanabe, P.Fons, K.Iwataand A.Yamada: "Growth of LiNbO3 epitaxial films by oxygen radical-assisted laser molecular beam epitaxy."
Applied Physics A· Vol.69 (1999) pp.679-681.
23) K.Iwata, P.Fons, S.Niki, A.Yamada, K.Matsubara and M. Watanabe: "Nitrogen induced defects in ZnO:N grown on sapphire substrate by gas source MBE."
J. Crystal Growth, 209 (2000) pp.526-531.
24) P.Fons, K.Iwata,S.Niki, A.Yamada, K.Matsubara and M. Watanabe: "Nitrogen induced defects in ZnO:N grown on sapphire substrate by gas source MBE."
J. Crystal Growth, 213 (2000) pp.532-536.
25) K.Iwata, P.Fons, A.Yamada, K.Matsubara and S.Niki: "ZnO growth on Si by radical source MBE."
J. Crystal Growth, 214/215 (2000) pp.50-54.
26) K.Iwata, P.Fons, A.Yamada, K.Matsubara, K. Nakahara, H. Takasu and S.Niki: "Improvement of Electrical Properties in ZnO Thin Films Grown by Radical source(RS)-MBE."
Physica Status Solidi (a) , Vol.180, No.1,(2000) p.287.
27) K.Iwata, P.Fons, A.Yamada, K.Matsubara, K. Nakahara, H. Takasu and S.Niki: "Improved Electrical Properties in ZnO Semiconductor Films Grown by Radical Source MBE."
Transactions of the Materials Research Society of Japan, 26 (2001) pp.993-996.
28) H. Takasu, K. Nakahara, P.Fons, K.Iwata, S.Niki, A.Yamada, K.Matsubara and R.Hunger: "Nucleation and Growth of ZnO on(11-20) Sapphire Substrates using Molecular Beam Epitaxy."
APPLIED PHYSICS LETTERS·79-25·(2001) pp.4135-4137.
29) P.Fons, K.Iwata, A.Yamada, K.Matsubara, K. Nakahara, T.Tanabe, H. Takasu and S.Niki: "Interactions between gallium and nitrogen dopants in ZnO films grown by radical-source molecular-beam epitaxy."
J. Crystal Growth, 227-1 (2001) pp.911-916.
30) P.Fons, K.Iwata, A.Yamada, K.Matsubara, K. Nakahara, H. Takasu and S.Niki: "A XANES Study of Cu Valency in Cu-Doped Epitaxial ZnO."
Physica Status Solidi (b) , Vol.229, No.2,(2002) pp.849-852.
31) K.Iwata, P.Fons, A.Yamada, K.Matsubara, K. Nakahara, H. Takasu and S.Niki: "Bandgap Engineering of ZnO Using Se."
Physica Status Solidi (b) , Vol.229, No.2,(2002) pp.887-890.
32) K. Nakahara, H. Takasu, P.Fons, A.Yamada, K.Iwata, K.Matsubara, R. Hunger and S.Niki: "Growth of N-doped and Ga plus N-codoped ZnO films by radical source molecular beam epitaxy."
J. Crystal Growth, 237 (2002) pp.503-508.
33) S.F.Chichibu, T.Sota, P.Fons, K.Iwata, A.Yamada, K.Matsubara, and S.Niki: "Photoreflectance and photoluminescence of exciton-polaritons in a ZnO epilayer grown on the a-face of sapphire by radical-source molecular-beam epitaxy."
Physica Status Solidi A-APPLIED RESEARCH, Vol.192-1, (2002) pp.171-176.
34) S.F.Chichibu, T.Sota, P.Fons, K.Iwata, A.Yamada, K.Matsubara, and S.Niki: "Observation of exciton-polariton emissions from a ZnO epitaxial film on the a-face of sapphire grown by radical-source molecular-beam-epitaxy."
JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES and REVIEW PAPERS·41-8b, (2002) pp.L935-L937.
35) K.Matsubara, P.Fons, K.Iwata, A.Yamada and S.Niki: "Room-temperature deposition of Al-doped ZnO films by oxygen radical assisted pulsed laser deposition."
THIN SOLID FILMS, Vol.422, (2002) pp.176-179.
36) K.Iwata, P.Fons, A.Yamada, K.Matsubara and S.Niki: "Natural ordering of ZnOSe grown by radical source MBE."
J. Crystal Growth, 251 (2003) pp.633-637.
37) K.Sakurai, R.Hunger, K.Matsubara, P.Fons, A.Yamada, K.Iwata, and S.Niki: "In Situ Deposition Rate Monitoring During the Three-Stage-Growth Process of Cu(In,Ga)Se2 Absorber Films."
THIN SOLID FILMS, Vol.431-432,(2003) pp.16-21.
38) A.Yamada, P.Fons, K.Matsubara, K.Iwata, K.Sakurai and S.Niki: "Estimation and correction procedure for the effects of surface roughness on electron probe microanalysis."
JAPANESE JOURNAL OF APPLIED PHYSICS·42-9A,(2003) pp.5811-5812.
39) K.Iwata, T.Sakemi, T.Yamamoto, K.Awai, H.Tampo, P.Fons, A.Yamada, K.Matsubara and S.Niki: "Material properties of ZnO thin film for photovoltaic devices grown by URT-IP method"
THIN SOLID FILMS, Vol.445,(2003) pp.274-277.
40) P.Fons, A.Yamada, K.Iwata, K.Matsubara, K. Nakahara, H. Takasu and S.Niki: "An EXAFS and XANES study of MBE grown Cu-doped ZnO."
NUCLEAR INSTRUMENTS and METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS, Vol.199, (2003) pp.190-194.
41) K.Iwata, T.Sakemi, T.Yamamoto, K.Awai, H.Tampo, P.Fons, A.Yamada, K.Matsubara, K. Nakahara, H. Takasu and S.Niki: "Doping properties of ZnO thin film for photovoltaic devices grown by URT-IP method."
THIN SOLID FILMS, Vol.451-452,(2004) pp.219-223.
42) P.Fons, H.Tampo, K.Nakahara, A.Yamada, K.Matsubara, K.Iwata, H.Takasu and S.Niki: "Thermal processing induced structural changes in ZnO films grown on (1120) sapphire substrates using molecular beam epitaxy."
PHYSICA STATUS SOLIDI A-APPLIED RESEARCH·1-4,(2004) pp.868-871.
43) H.Shibata, M.Watanabe, M.Sakai, K.Oka, P.Fons, K.Iwata, A.Yamada, K.Matsubara, K.Sakurai, H.Tampo, K.Nakahara and S.Niki: "Characterization of ZnO crystals by photoluminescence spectroscopy."
PHYSICA STATUS SOLIDI (C)·1,(2004) pp.872-875.
44) H.Tampo, A.Yamada, P.Fons, H.Shibata, K.Matsubara, K.Iwata, K. Nakahara, H. Takasu and S.Niki: "Degenerate layers in epitaxial ZnO films grown on sapphire substrates."
APPLIED PHYSICS LETTERS·84-22·(2004) pp.4412-4414.
45) K.Matsubara, H.Tampo, H.Shibata, A.Yamada, P.Fons, K.Iwata and S.Niki: "Bandgap modified Al-doped Zn1-xMgxO transparent conducting films deposited by pulsed laser deposition."
APPLIED PHYSICS LETTERS·85-8·(2004) pp.1374-1376.
46) A.Yamada, K.Matsubara, K.Sakurai, S.Ishizuka, H.Tampo, P.Fons, K.Iwata and S.Niki: "Effect of band offset on the open circuit voltage of heterojunction CuIn1-xGaxSe2 solar cells."
APPLIED PHYSICS LETTERS·85-23·(2004) pp.5607-5609.
47) S.Ishizuka, K.Sakurai, A.Yamada, K.Matsubara, P.Fons, K.Iwata, S.Nakamura, Y.Kimuraw, R.Baba, H.Nakanishi, T.Kojima and S.Niki: "Fabrication of wide-gap Cu(In1-xGax)Se2 thin film solar cells: a study on the correlation of cell performance with highly resistive i-ZnO layer thickness."
SOLAR ENERGY MATERIALS AND SOLAR CELLS·87-1-4·(2005) pp.541-548.
48) K.Iwata, T.Sakemi, T.Yamamoto, K.Awai, H.Tampo, P.Fons, A.Yamada, K.Matsubara, K. Nakahara, H. Takasu and S.Niki: "Improvement of ZnO TCO film growth for photovoltaic devices by reactive plasma deposition (RPD)."
THIN SOLID FILMS, Vol.480-481,(2005) pp.199-203.
49) K.Iwata, H.Tampo, P.Fons, A.Yamada, K.Matsubara, and S.Niki: "Growth of ZnO and device application."
APPLIED SURFACE SCIENCE, Vol.244, No.4,(2005) pp.504-510.
50) H.Tampo, H.Shibata, K.Kim, P.Fons, A.Yamada, K.Matsubara, K.Iwata, K.Tamura, H.Takasu and S.Niki: "The effects of thermal treatments on the electrical properties of phosphorus doped ZnO layers grown by MBE."
J. Crystal Growth, 278 (2005) pp.268-272.
51) M.Watanabe, M.Sakai, H.Shibata, H.Tampo, P.Fons, K.Iwata, A.Yamada, K.Matsubara, K.Sakurai, S.Ishizuka, K.Nakahara, H.Takasu and S.Niki: "Photoluminescence characterization of excitonic centers in ZnO epitaxial films."
APPLIED PHYSICS LETTERS·86-22,(2006) pp.221907-1-221907-3.
52) H.Shibata, H.Tampo, M.Sakai, A.Yamada, K.Matsubara, K.Sakurai, S.Ishizuka, K.Kim, P.Fons, K.Iwata, K.Tamura, H.Takasu, K.Maeda, I.Niikura and S.Niki: "Photoluminescence Recombination Centers in ZnO Crystals."
PHYSICA STATUS SOLIDI (C)·3-4,(2006) pp.1026-1029.
53) Y.Kobayashi, D.Yoshitomi, K.Iwata, H.Takada and K.Torizuka: "Ultrashort pulse characterization by ultra-thin ZnO, GaN, and AlN crystals."
OPTICS EXPRESS·15-15,(2007) pp.9748-9754.
54) K.Iwata, M. Onda and K. Komoriya: "UAV for Small Cargo Transportation."
AIAA Meeting Papers On Disc·AIAA Infotech@aerospace 2007 Conferencen and Exhibit·9-2784·pp.1-6, (2007).
55) K.Iwata: "Aerial Robotic System for Transportation and Logistics."
Cargo Handling JAPAN·Vol.52, No.2, (2007) pp.207-212.
56) K.Iwata, M. Onda and K. Komoriya: "Aerial Robotic System for Transportation and Logistics."
Journal of Mechanical Systems for Transportation and Logistics(JMTL)·Vol.1, No.1,(2008) pp.146-157.

List of my presentation in international conference

1) J.H.Kim, H.Asahi, K.Asami, K.Iwata, S.G.Kim, S.Gonda: "Growth temperature dependence of optical properties of gas source MBE grown GaP/AlP short period superlattices"
3rd International Symposium on Atomic Layer Epitaxy and Related Surface Processes, Sendai, Japan, May, 1994 Workbook pp.62-63
2) K.Iwata, H.Asahi, J.H.Kim, X.F.Liu, S.Gonda, Y.Kawaguchi, T.Matsuoka: "Gas source MBE growth of InAlP band offset reduction layer on p-type ZnSe"
8th International Conference on Molecular Beam Epitaxy, Osaka, Japan, August, 1994 Workbook pp.285-286
3) J.H.Kim, H.Asahi, K.Asami, K.Iwata, S.G.Kim, T.Ogura, S.Gonda: "Gas source MBE growth of GaP/AlP modulated superlattices and their optical properties"
8th International Conference on Molecular Beam Epitaxy, Osaka, Japan, August, 1994 Workbook pp.80-81
4) K.Iwata, H.Asahi, T.Ogura, S.Gonda, A.Ohki, Y.Kawaguchi, T.Matsuoka: "Low temperature grown Be-doped InAlP band offset reduction layer to p-type ZnSe"
7th International Conference on Indium Phosphide and Related Materials, Sapporo, May, 1995
5) K.Iwata, H.Asahi, S.J.Yu, M.Fushida, K.Asami and S.Gonda: "High quality GaN growth on (0001) sapphire by ion-removed ECR-MBE and first observation of (2x2) and (4x4) reconstruction RHEED patterns."
Topical Workshop on III-V Nitrides '95, Nagoya, Japan, September, 1995
6) K.Iwata, H.Asahi, S.J.Yu, K.Asami, M.Fushida and S.Gonda: "ECR-MBE growth of III-V nitrides with ion-removed radical cell."
International Symposium on Blue Laser and Light Emitting Diodes, Chiba Univ.,Japan, March, 1996
7) K.Iwata, H.Asahi, K.Asami and S.Gonda: "Gas source Molecular Beam Epitaxy growth of GaN rich side of GaN1-xPx using Ion-Removed Electron Cyclotron Resonance radical cell."
9th International Conference on Molecular Beam Epitaxy, Malibu, California, U.S.A., August, 1996 Workbook pp.2.7
8) K.Iwata, P.Fons, S.Niki, A.Yamada, K.Matsubara and M. Watanabe: "Nitrogen induced defects in ZnO:N grown on sapphire substrate by gas source MBE."
7th International Conference on Chemical Beam Epitaxy and Related Growth Techniques;
Tsukuba International Convention Center, Tsukuba, JAPAN
We3-19 presented on Wednesday, July 28, 1999.
9) K.Iwata, P.Fons, A.Yamada, K.Matsubara and S.Niki: "ZnO growth on Si by Radical Source MBE."
9th International Conference on II-Vi compounds;
Kyoto International Convention Center, Kyoto, JAPAN
November 5, 1999.
10) K.Iwata, P.Fons, A.Yamada, K.Matsubara , K. Nakahara, H. Takasu and S.Niki: "Improvement of Electrical Properties in ZnO Thin Films Grown by Radical source(RS)-MBE."
The 3th International Symposium on Blue Laser and Light Emitting Diodes;
Zeuthen, Berlin, GERMANY
6-10 March 2000.
11) K.Iwata, P.Fons, A.Yamada, K.Matsubara and S.Niki: "ZnO semiconductor growth by Ozone-MBE."
The 13th International Conference on Crystal Growth in Conjunction with
The 11th International Conference on Vapor Growth and Epitaxy;
Doshisya university, Kyoto, JAPAN
2001.7.30-8.4.
12) K.Iwata, P.Fons, A.Yamada, K.Matsubara and S.Niki: "Bandgap engineering of ZnO using Se."
The 10th International conference on II-VI semiconductor ;
UNIversum Convention Center, Bremen, GERMANY
9-14 September 2001.
13) K.Iwata, P.Fons, A.Yamada, K.Matsubara and S.Niki: "Natural ordering of ZnOSe grown by radical source MBE"
12th International Conference on Molecular Beam Epitaxy ;
San Francisco, USA
2002/09/18.
14) K.Iwata, P.Fons, A.Yamada, K.Matsubara and S.Niki: "Bandgap Narrowing of ZnOSe films grown by radical source MBE"
2nd International Workshop on Zinc Oxide ;
Dayton, USA
2002/10/23.
15) K.Iwata,T.Sakemi, T.Yamamoto, K.Awai, H.Tampo, P.Fons, A.Yamada, K.Matsubara and S.Niki: "Material properties of ZnO thin film for photovoltaic devices grown by URT-IP method"
The 3rd International Symposium on Transparent Oxide Thin Films for Electronics and Optics ;
Tokyo, JAPAN
2003/04/10.
16) K.Iwata,T.Sakemi, T.Yamamoto, K.Awai, H.Tampo, P.Fons, A.Yamada, K.Matsubara and S.Niki: "Doping properties of ZnO thin film for photovoltaic devices grown by URT-IP method"
Europian Material Research Society 2003 Spring Meeting ;
Strasbourg, FRANCE
2003/06/11.
17) K.Iwata,T.Sakemi, T.Yamamoto, K.Awai, H.Tampo, P.Fons, A.Yamada, K.Matsubara and S.Niki: "Improvement of ZnO TCO film growth for photovoltaic devices by reactive plasma deposition (RPD)"
Europian Material Research Society 2004 Spring Meeting ;
Strasbourg, FRANCE
2004/05/25.
18) K.Iwata, H.Tampo, P.Fons, A.Yamada, K.Matsubara and S.Niki: "Growth of ZnO and device application"
12th international Conference on Solid Films and Surfaces (ICSFS-12);
Hamamatsu, JAPAN
2004/06/23.
19) K.Iwata, M. Onda and K. Komoriya: "UAV for Small Cargo Transportation"
AIAA Infotech@aerospace 2007 Conferencen and Exhibit;
Rohnert Park, USA
2007/05/08.

Awards

1) EMS Award for Young Researcher: THE 16TH ELECTRONIC MATERIALS SYMPOSIUM 1997;
19 - 21 JUNE 1997, Osaka, Japan
2) Young Scientist Award for the Presentation of an Excellent Paper: The 49th Spring Meeting, 2002; The Japan Society of Applied Physics and Related Societies
27 - 30 March 2002, Tokyo, Japan
3) Award for Transportation and Logistics Division in the Japan Society of Mechanical Engineers, Certificate of Merit for Outstanding Presentation: The 16th Transportation and Logistics Conference (TRANSLOG2007) ; The Japan Society of Mechanical Engineers
12 March 2007, Tokyo, Japan

List of my work