NUCLEAR INSTRUMENTS AND METHODS IN PHYSICS RESEARCH SECTION B
The tables of contents are generated automatically and are based on the data records of the individual contributions available in the index of the TIB portal. The display of the Tables of Contents may therefore be incomplete.
Table of contents
- 3
-
Influence of ionization processes on radiation defect formationAscheron, C. / Biersack, J. P. / Goppelt-Langer, P. et al. | 1993
- 7
-
Solid effect on the electronic stopping and application to range estimationNakagawa, S. T. et al. | 1993
- 12
-
The effect of high charge states on the stopping and ranges of ions in solidsBiersack, J. P. et al. | 1993
- 16
-
Numerical evaluation of the electronic stopping power for heavy ions in solidsWang, Y.-N. / Ma, T.-C. et al. | 1993
- 20
-
Chemical bond effects on the low-energy electronic stopping power of Li and He ions on saturated alcohols, ethers and aminesSoullard, J. / Cruz, S. A. / Cabrera-Trujillo, R. et al. | 1993
- 24
-
Double scattering in elastic recoil spectraRepplinger, F. / Stoquert, J. P. / Siffert, P. et al. | 1993
- 28
-
Computer simulation of channeling implantation at high and medium energiesPosselt, M. et al. | 1993
- 33
-
Energy loss and equilibrium charge distribution of nitrogen ions transmitted through thin silicon crystalsBentini, G. G. / Bianconi, M. / Nipoti, R. et al. | 1993
- 37
-
Energy loss and straggling of MeV ^4He ions in a Si/Sb multilayer targetNiemann, D. / Oberschachtsiek, P. / Kalbitzer, S. et al. | 1993
- 41
-
Electronic stopping of hydrogen ions in graphite and amorphous carbonNecas, V. / Kaeferboeck, W. / Roessler, W. et al. | 1993
- 45
-
Kinetic approach to multiple scattering of heavy ions in the channeling regimeMuralev, V. A. et al. | 1993
- 49
-
Shell effects observed in exit charge state distributions of 1-30 keV atomic projectiles transiting ultrathin carbon foilsFunsten, H. O. / Barraclough, B. L. / McComas, D. J. et al. | 1993
- 53
-
Range parameters of Au and Cs implanted into BN and SiC filmsFichtner, P. F. P. / Herberts, M. R. / Grande, P. L. et al. | 1993
- 58
-
Channeling effects in high energy ion implantation: Si(N)Berti, M. / Brusatin, G. / Carnera, A. et al. | 1993
- 62
-
Range measurement of boron isotopes in silicon from 600 keV to 2 MeVGoppelt, P. / Biersack, J. P. / Gebauer, B. et al. | 1993
- 65
-
Electronic stopping effects in Fe~6~0Co~4~0 films irradiated with high energy ionsRiviere, J. P. / Dinhut, J. F. / Paumier, E. et al. | 1993
- 73
-
Collision cascades in Zr~3FeHowe, L. M. / Rainville, M. H. / Phillips, D. et al. | 1993
- 80
-
Valence and conduction band electronic distributions in ion beam prepared samplesBelin, E. / Traverse, A. / Sonder, A. et al. | 1993
- 86
-
Radiation-induced disordering and defect production in Cu~3Au and Ni~3Al studied by molecular dynamics simulationDiaz de la Rubia, T. / Caro, A. / Spaczer, M. et al. | 1993
- 91
-
An ion beam mixing model for compound formation: the case of Pd/SiDesimoni, J. / Traverse, A. et al. | 1993
- 94
-
Simulation of ion sputtering of rotating amorphous or polycrystalline solidsWege, S. / Bautsch, M. / Ruebesame, D. et al. | 1993
- 98
-
On the efficiency of deposited energy density for ion beam mixing processes with ions implanted during and after thin metal film depositionTashlykov, I. S. / Belyi, I. M. / Bobrovich, O. G. et al. | 1993
- 102
-
Instability of homogeneous distribution of radiation defects in metals in the case of heavily fluctuating defect productionDevyatko, Y. N. / Makletsov, A. A. / Tronin, V. N. et al. | 1993
- 106
-
Defect distributions in MeV ion bombarded siliconHallen, A. / Svensson, B. G. et al. | 1993
- 110
-
Fluence dependent concentration of low-energy Ga implanted in SiGnaser, H. / Steltmann, J. / Oechsner, H. et al. | 1993
- 115
-
Self-organizing processes in metals by low-energy ion beamsTereshko, I. V. / Khodyrev, V. I. / Tereshko, V. M. et al. | 1993
- 120
-
Ion-beam induced atomic transport at the Sb/Ni interfaceShi, F. / Weber, T. / Bolse, W. et al. | 1993
- 124
-
Ion monitoring of ion beam dynamic mixing processChayahara, A. / Kiuchi, M. / Mokuno, Y. et al. | 1993
- 128
-
Damage profiles in MgO single crystals after krypton implantationFriedland, E. et al. | 1993
- 132
-
Giant radiation damage produced by the impact of heavy molecular onto silicon single crystalCerofolini, G. F. / Bertoni, S. / Meda, L. et al. | 1993
- 137
-
A refined model of the interface mixing in local thermal spikesBolse, W. et al. | 1993
- 142
-
Investigation of thin films by high-energy ERDAGoppelt, P. / Biersack, J. P. / Gebauer, B. et al. | 1993
- 146
-
Time and energy dependent recoil distributions in mixturesBrasure, L. W. / Prinja, A. K. et al. | 1993
- 151
-
The ultimate depth resolution in SIMS profiling: low-energy ion beam mixing of Au-Pt interfaceLikonen, J. / Hautala, M. / Koponen, I. et al. | 1993
- 159
-
Atomic transport in ion mixed Pd/Co bilayerChae, K. H. / Jang, H. G. / Song, J. H. et al. | 1993
- 163
-
Ion beam mixing isotopic silver bilayers by 200 keV germaniumKing, B. V. / Jeynes, C. / Webb, R. P. et al. | 1993
- 167
-
Ion beam mixing of ceramic/metal interfacesCorts, T. / Traverse, A. / Bolse, W. et al. | 1993
- 172
-
Computer simulation of point-defect distributions generated by ion implantationJaraiz, M. / Arias, J. / Rubio, J. E. et al. | 1993
- 176
-
Lattice location and annealing studies of heavy ion implanted diamondHofsaess, H. / Restle, M. / Wahl, U. et al. | 1993
- 180
-
Lattice location of Er in GaAs and Al~0~.~5Ga~0~.~5As layers grown by MBE on (100) GaAs substratesAlves, E. / Da Silva, M. F. / Evans, K. R. et al. | 1993
- 184
-
Mercury implanted into aluminium: temperature and concentration dependence of the substitutional componentKhubeis, I. / Meyer, O. et al. | 1993
- 188
-
Lattice location and migration of lead in ironJagielski, J. / Turos, A. et al. | 1993
- 192
-
Lattice site occupation of iodine implanted into aluminiumHauser, T. / Gerber, R. / Xiong, G. C. et al. | 1993
- 196
-
Lattice location of implanted fluorine in diamondSmallman, C. G. / Fearick, R. W. / Derry, T. E. et al. | 1993
- 201
-
-NMR of ^1^2B in Si: a low-dose implantation studyFischer, B. / Seelinger, W. / Frank, H.-P. et al. | 1993
- 207
-
Recent advances in ion beam modification of metalsSmidt, F. A. / Hubler, G. K. et al. | 1993
- 217
-
Microscopic characteristics and electrochemical properties of carbon-implanted steels in a non-aqueous acetic acid mediumUeda, Y. / Sekiguchi, A. / Yuasa, M. et al. | 1993
- 221
-
Effect of Mg segregation at grain boundaries on corrosion behavior of intermetallic compound Ni~3Al(B)Liu, X. / Jian, B. / Wang, X. et al. | 1993
- 225
-
Wear resistance of boron nitride coated metalAndoh, Y. / Nishiyama, S. / Sakai, S. et al. | 1993
- 229
-
Study of surface modification of WC-Co alloy by nitrogen implantationShi, W. D. / Wen, X. Y. / Liu, J. H. et al. | 1993
- 233
-
Improvement in wear characteristics of steel tools by metal ion implantationRueck, D. M. / Boos, D. / Brown, I. G. et al. | 1993
- 237
-
Metallurgical study on hardness distribution by high energy ion implantation taking notice of solid-solubilityHigeta, K. / Yoshida, Y. / Sato, M. et al. | 1993
- 242
-
Pulsed ion sources for surface modification of materialsKorenev, S. et al. | 1993
- 246
-
Improvement of rolling contact fatigue life of ion implanted M50 steelTorp, B. / Nielsen, B. R. / Dodd, A. et al. | 1993
- 250
-
Characteristics of the nitrogen ion implanted intermetallic compound TiAlWang, X. / Yang, Y. / Liu, X. et al. | 1993
- 254
-
Effects of implantation treatments on micromechanical properties of M2 steelAlonso, F. / Viviente, J. L. / O�ate, J. I. et al. | 1993
- 258
-
Depth profiles of C, N and O on carbon coated steel surfaces made by IBADKolitsch, A. / Hentschel, E. / Richter, E. et al. | 1993
- 262
-
A comparison of plasma immersion ion implantation with conventional ion implantationKenny, M. J. / Wielunski, L. S. / Tendys, J. et al. | 1993
- 267
-
The pitting corrosion behavior of aluminum ion implanted with titaniumYao, X. Y. / Kumai, C. S. / Devine, T. M. et al. | 1993
- 271
-
Improvement of physical and chemical properties of steel implanted with Cr^+, Ti^+, Si^+ ionsTashlykov, I. S. / Belyi, I. M. / Bobrovich, O. G. et al. | 1993
- 275
-
Electrochemical absorption of hydrogen into N^+, O^+ and Ar^+ implanted palladium electrodesTakahashi, K. / Ueshima, M. / Iwaki, M. et al. | 1993
- 279
-
Electrochemical behavior of titanium implanted with nickel and tantalum ionsSugizaki, Y. / Yasunaga, T. / Satoh, H. et al. | 1993
- 285
-
Aqueous corrosion of ion beam mixed Ta films on 13% chromium steelHuang, N. K. et al. | 1993
- 289
-
High temperature oxidation of ion implanted 2011 aluminium alloyChu, J. W. / Dytlewski, N. / Evans, P. J. et al. | 1993
- 294
-
Ion implantation of Raney copper catalystsDurbach, S. / Mellor, J. / Coville, N. J. et al. | 1993
- 297
-
The effects of Ti implantation on corrosion and adhesion of TiN coated stainless steelBaba, K. / Nagata, S. / Hatada, R. et al. | 1993
- 303
-
Phase formation in iron after high-fluence ion implantationRauschenbach, B. et al. | 1993
- 309
-
CEMS study of ^5^7Fe implantation in nickelMarest, G. / Parellada, J. / Principi, G. et al. | 1993
- 313
-
Modification of the thermal behavior of iron-carbonitrides induced by Kr bombardment on nitrogen-implanted low carbon steelFoerster, C. E. / Amaral, L. / Moncoffre, N. et al. | 1993
- 317
-
Evolution of lead precipitates in ion implanted aluminiumBourdelle, K. K. / Johansen, A. / Schmidt, B. et al. | 1993
- 323
-
Investigation of buried AIN layers formed by nitrogen implantation into AlLin, C. / Li, Y. / Kilner, J. A. et al. | 1993
- 327
-
Enhanced stability of nitrides in -Fe co-implanted with Cr + N or Al + NKopcewicz, M. / Jagielski, J. / Turos, A. et al. | 1993
- 332
-
Formation of metastable carbide and fractal structure in Co thin films by carbon ion implantationLiu, B. X. / Tao, K. et al. | 1993
- 336
-
Characteristics of tool steel implanted with multi-energy B^+ and single-energy N~2^+ ionsOhtani, S. / Mizutani, Y. / Takagi, T. et al. | 1993
- 340
-
Microstructure and tribology of nitrogen implanted molybdenum and tungstenPalmetshofer, L. / Roedhammer, P. et al. | 1993
- 344
-
Introduction of nitrogen into metals by high intensity pulsed ion beamsPiekoszewski, J. / Langner, J. / Bialoskorski, J. et al. | 1993
- 348
-
High dose implantation of aluminium into ironReuther, H. / Nikolov, O. / Kruijer, S. et al. | 1993
- 352
-
An investigation of phase formation by high dose silicon ion implantation into nickelRao, Z. / Williams, J. S. / Pogany, A. P. et al. | 1993
- 357
-
Aggregation of iron implants in silverMarest, G. / Jaffrezic, H. / Stanek, J. et al. | 1993
- 363
-
The prediction of phases in ion beam mixed multilayersBaumvol, I. J. R. et al. | 1993
- 370
-
Amorphization of metallic alloys by ion bombardmentZiemann, P. / Miehle, W. / Plewnia, A. et al. | 1993
- 379
-
Amorphous and quasicrystalline AlMn and AlFe phase synthesis by ion beam mixing and related transport propertiesPlenet, J. C. / Perez, A. / Rivory, J. et al. | 1993
- 386
-
In situ TEM study of ion induced amorphization at low temperature in Al~3TiJaouen, C. / Denanot, M. F. / Riviere, J. P. et al. | 1993
- 390
-
On the phase formation during ion beam mixing of Al-TiKyllesbech Larsen, K. / Skovmand, S. / Karpe, N. et al. | 1993
- 394
-
Ion beam mixing of TiC/Fe bilayersGesan, P. / Delafond, J. / Cahoreau, M. et al. | 1993
- 398
-
The effect of pre- and postimplantation of carbon on the phase formation and surface mechanical properties of an ion beam mixed Fe-Ti multilayered systemHirvonen, J.-P. / Nastasi, M. / Jervis, T. R. et al. | 1993
- 404
-
X-ray diffraction study of residual stress modification in Cu/W superlattices irradiated by light and heavy ionsBadawi, K. F. / Goudeau, P. / Pacaud, J. et al. | 1993
- 408
-
phase formation and dissolution under ion irradiation in Cu/Pd thin filmsQuan, Z. / Naundorf, V. / Macht, M.-P. et al. | 1993
- 412
-
Diffusion-induced grain boundary migration during ion beam mixing Au/Cu bilayersAlexander, D. E. / Baldo, P. M. / Rehn, L. E. et al. | 1993
- 417
-
Mixing effect of Fe/Ni multilayers of overall Fe~6~5Ni~3~5 compositionTosello, C. / Ferrari, F. / Brand, R. et al. | 1993
- 421
-
Construction of free energy diagram and phase formation by ion mixing in the Ni-Nb systemBai, H. Y. / Zhang, Z. J. / Liu, B. X. et al. | 1993
- 424
-
Amorphization of In/Au-bilayers by low temperature ion beam mixingMiehle, W. / Plewnia, A. / Ziemann, P. et al. | 1993
- 428
-
Effect of ion beam irradiation in amorphous ferromagnetic alloysMatsumoto, N. / Bang, L. / Maeta, H. et al. | 1993
- 432
-
Surface composition changes of CuBe alloys under Ar^+ ion bombardment studied by Auger electron spectroscopyShopov, A. V. / Vichev, R. G. / Karpuzov, D. S. et al. | 1993
- 436
-
Ion beam mixing of Fe/Al multilayers: a CEMS studyAlexandre, J. L. / Vasconcellos, M. A. Z. / Huebler, R. et al. | 1993
- 445
-
A comparison of IBAD films for wear and corrosion protection with other PVD coatingsEnsinger, W. / Schroeer, A. / Wolf, G. K. et al. | 1993
- 455
-
RBS and channeling study of the correlation between ion beam mixing and amorphization in a binary metal systemBenkoulal, T. / Jagielski, J. / Thome, L. et al. | 1993
- 459
-
Low energy ^1^5N and ^1^4N implantation in chromium analysed by NRA and RBSRose, M. / Baumann, H. / Markwitz, A. et al. | 1993
- 463
-
Properties of carbon nitride thin films prepared by ion and vapor depositionChubaci, J. F. D. / Sakai, T. / Yamamoto, T. et al. | 1993
- 467
-
Corrosion stability of TiN prepared by ion implantation and PVDHeide, N. / Schultze, J. W. et al. | 1993
- 472
-
Hydride formation in zirconium and titanium as a result of low energy ion bombardmentJackman, J. A. / Carpenter, G. J. C. / McCaffrey, J. et al. | 1993
- 476
-
Defect formation and defect-impurity interaction in the hexagonal transition metals Re and LuKoch, H. / Vianden, R. et al. | 1993
- 480
-
Behavior of nitrogen implanted into Zr at high fluenceMiyagawa, S. / Ikeyama, M. / Saitoh, K. et al. | 1993
- 485
-
High dose carbon implantation in nickelZhang, Z. H. / Chow, L. / Tao, Y. K. et al. | 1993
- 491
-
Phase transformations in Mo under simultaneous implantation of metal and gas ionsTyumentsev, A. N. / Pinzhin, Y. P. / Korotaev, A. D. et al. | 1993
- 496
-
Evolution of profiles of implanted nitrogen in metal bilayersBourdelle, K. K. / Boerma, D. O. et al. | 1993
- 501
-
High dose implantation of yttrium and barium ions into copper: the use of a sacrificial carbon layer for enhanced retentionClapham, L. / Whitton, J. L. / Rueck, D. et al. | 1993
- 507
-
MeV implantation into semiconductorsWilliams, J. S. / Elliman, R. G. / Ridgway, M. C. et al. | 1993
- 514
-
Mechanisms of amorphization in ion implanted crystalline siliconCampisano, S. U. / Coffa, S. / Raineri, V. et al. | 1993
- 519
-
Channeling and TEM investigations of pulse electron beam annealed GaAs implanted with PbAlberts, H. W. / Gaigher, H. L. / Bredell, L. J. et al. | 1993
- 523
-
The displacement damage produced in Si by 590 MeV protonsAlurralde, M. / Paschoud, F. / Victoria, M. et al. | 1993
- 528
-
Annealing of defects created in silicon by MeV ion implantationSealy, L. / Barklie, R. C. / Brown, W. L. et al. | 1993
- 532
-
Ion implantaion damage and annealing in GaSbCallec, R. / Poudoulec, A. / Salvi, M. et al. | 1993
- 538
-
Dose rate dependence of the ion-beam-induced epitaxial crystallization in siliconHeera, V. / Koegler, R. / Skorupa, W. et al. | 1993
- 543
-
Swelling of GaSb at low energies (1.3-14.5 keV)Gauneau, M. / Chaplain, R. / Rupert, A. et al. | 1993
- 548
-
The effect of defects caused by Xe ion bombardment on the structure of Au/GaAs contactsJaroli, E. / Gyulai, J. / Pecz, B. et al. | 1993
- 552
-
Strain distribution in As^+ and Sb^+ ion implanted and annealed <100> SiHorvath, Z. E. / Peto, G. / Zsoldos, E. et al. | 1993
- 556
-
Reduced reverse temperature of ion beam induced amorphization/crystallization for intermittent beam irradiation of silicon?Koegler, R. / Heera, V. / Skorupa, W. et al. | 1993
- 559
-
Dynamics of void formation during implantation of Si under self-annealing conditions and their influence on dopant distributionLulli, G. / Merli, P. G. / Migliori, A. et al. | 1993
- 564
-
In situ detection of rearrangement processes during electron beam annealing of ion implanted InPMaurer, C. / Kallweit, R. / Baumann, H. et al. | 1993
- 569
-
Distribution of strain in Ge ion implanted silicon measured by high resolution X-ray diffractionPesek, A. / Kastler, P. / Lischka, K. et al. | 1993
- 573
-
Defect levels in silicon bombarded with light ionsReisinger, J. / Palmetshofer, L. et al. | 1993
- 578
-
Pulsed UV laser irradiation effect for Sn^+-implanted GaAsShibata, H. / Makita, Y. / Ikeda, T. et al. | 1993
- 583
-
Near-surface defects formed by MeV ion implantation into siliconSayama, H. / Kinomura, A. / Yuba, Y. et al. | 1993
- 583
-
Generation rate of point defects in silicon irradiated by MeV ionsSvensson, B. G. / Jagadish, C. / Williams, J. S. et al. | 1993
- 591
-
Annealing behavior of damage in Si-implanted InP studied by piezoelectric detection of photoacoustic signalYoshinaga, H. / Kawai, J. / Agui, T. et al. | 1993
- 596
-
The kinetics of self ion amorphization of siliconGoldberg, R. D. / Elliman, R. G. / Williams, J. S. et al. | 1993
- 603
-
Conductivity changes and impurity-defect interactions in ion-implanted amorphous siliconCoffa, S. / Priolo, F. / Poate, J. M. et al. | 1993
- 607
-
Photon assisted implantation (PAI)Biro, L. P. / Gyulai, J. / Ryssel, H. et al. | 1993
- 612
-
Analysis of the SiO~2 defects originated by phosphorus implantation in MOS structuresBota, S. A. / Montserrat, J. / Perez-Rodriguez, A. et al. | 1993
- 616
-
Optical investigation of implantation damage in GaAs/AlGaAs quantum wellsKieslich, A. / Straka, J. / Forchel, A. et al. | 1993
- 620
-
Paramagnetic defects in silicon irradiated with 40 MeV As ionsDvurechenskii, A. V. / Karanovich, A. A. / Rybin, A. V. et al. | 1993
- 624
-
X-ray diffraction analysis of damage accumulation due to the nuclear energy loss of 50 keV and 1-2.2 MeV B ions implanted in siliconFabbri, R. / Lulli, G. / Nipoti, R. et al. | 1993
- 628
-
TEM study of Si^+, Ge^+ and C^+ implanted siliconKikuchi, Y. / Kase, M. / Kimura, M. et al. | 1993
- 632
-
Electrical and optical characterization of defect levels caused in InGaAs by boron ion implantationYamamura, S. / Kimura, T. / Yugo, S. et al. | 1993
- 636
-
Disorder in high-dose, high-energy O- and Si-implanted SiEllingboe, S. L. / Ridgway, M. C. et al. | 1993
- 640
-
Gold and platinum accumulation on buried defects in siliconRohr, P. / Grob, J. J. / Siffert, P. et al. | 1993
- 644
-
Incorporation of In into Si preamorphized with Si, Ge and SnVianden, R. / Gwilliam, R. / Sealy, B. et al. | 1993
- 647
-
Damage distribution in GaAs implanted at elevated temperatureKalitzova, M. / Karpuzov, D. / Pashov, N. et al. | 1993
- 653
-
Optical doping of silicon with erbium by ion implantationPolman, A. / Custer, J. S. / Snoeks, E. et al. | 1993
- 659
-
High energy implantation of ^1^0B and ^1^1B into (100) silicon in channel and in random directionBogen, S. / Gong, L. / Frey, L. et al. | 1993
- 663
-
Radiation defects passivation by neutron irradiation of hydrogen-implanted siliconBolotov, V. V. / Emeksuzyan, V. M. / Plotnikov, G. L. et al. | 1993
- 667
-
Negative differential resistance in proton-beam modified siliconBolotov, V. V. / Emeksuzyan, V. M. / Plotnikov, G. L. et al. | 1993
- 670
-
The activation energy of electrical conduction of ion beam mixed Sb/n-Si Schottky contactsMalherbe, J. B. / Weimer, K. P. / Friedland, E. et al. | 1993
- 674
-
Codoping effects of As and Xe on ion-beam-induced epitaxial crystallization of SiHasegawa, M. / Kobayashi, N. / Hayashi, N. et al. | 1993
- 679
-
An explanation of transient-enhanced diffusion and electrical activation of boron in crystalline silicon during postimplantation annealingJaeger, H. U. et al. | 1993
- 683
-
Ion implantation of zirconium and hafnium in InP and GaAsKnecht, A. / Kuttler, M. / Scheffler, H. et al. | 1993
- 687
-
Formation and characterization of shallow junctions by through-film ion implantation in GaAsShen, H. L. / Xu, H. L. / Xia, G. Q. et al. | 1993
- 691
-
Properties of Mn^+-implanted GaAsNiki, S. / Makita, Y. / Yamada, A. et al. | 1993
- 697
-
Ion implanted arsenic in siliconNylandsted Larsen, A. / Christensen, B. / Christensen, P. H. et al. | 1993
- 702
-
Structural characterization of nitrogen ion implantation into silicon for sensor technologyRomano-Rodriguez, A. / El-Hassani, A. / Samitier, J. et al. | 1993
- 706
-
Structural and optical characterization of implanted and annealed semi-insulating GaAsTrudeau, Y. B. / Ares, R. / Kajrys, G. E. et al. | 1993
- 711
-
Defect production, annealing and electrical activation in Si^+ implanted InPWendler, E. / Mueller, P. / Bachmann, T. et al. | 1993
- 716
-
High energy ion implantation in GaAsWesch, W. / Wendler, E. et al. | 1993
- 721
-
Low temperature recrystallization of ion implanted InPMueller, P. / Wesch, W. / Solovyev, V. S. et al. | 1993