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18074903.Pdf H 4*; f- nvi (flfffiSC) JKSl f". (1OT.S!) nm Mi ii'.lk $t&. (IS I'tH l/r-ffi) ir.jlli ftk UlllliKlfttl'tHi) III ft fllif (IS! * ittt (MIU r.-'PiS) 'i<t» if* (ttifitivm,*) ft i &ti dci rfe1 i.-'i-'-wi .H »"(!W| iii*.!i r (ttifi't'i' i.7:M) ("Ifl iT (ihp'i'i?) I'.tf IS M| (T< 7 |---7,'3il Japan Aloniir KucrRy Research InsliluU' Hnard of Editors Hakubi Sasaki (Chief Editorl Juii Akaishi Hideo Kzurc Taken Fujino ^ oshiaki Futamura Miyuki HaRhvara Masahi lizumi Kalsuichj Ikawa Vukii) Ishiguro Ynshihiko Kaneko Ilinishi Kawamura Saloru Kawasaki Mirnshi Kudo Keizo Makuuchi ^'nshio Murao Susumu Muraoka ^'ukin Obala Tatsun Oku Shiiizo Sailci Naomoto Shikazono Nnbutake Suzuki Yasuo Suzuki Knzo Tachikawa Tatsunki Takeda Kazuvuki Tamura Akira Vamamnto JAERI u .t-- h li, II 4<IHi )•• i, n (T3HM1 -^ is') *1- JAERI reports are reviewed by the Board of Editors and issued irregularly. Inquiries about availability of the reports should be addressed to Information Division Department of Technical Information, Japan Atomic Energy Research Institute, Tokaimura. Naka-gun, Ibarakiken 319-11, Japan. ©Japan Atomic Energy Research Institute. 1987 nil m M *» IAER1 1304 Studies on Surface Chemical States of Some Metals and Ceramics Bombarded with Energetic Light-ions Yuji BABA Department of Chemistry Tokai Research Establishment Japan Atomic Energy Research Institute Tokai-inura, Naka-gun, Ibaraki-ken (Received August 11, 1986) Abstract An electron spectroscopy was applied to the investigation of surface chemical state of some metals and ceramics bombarded witli energetic light ions. Bombardments of kcV-order hydrogen tons on scandium, titanium, vanadium, yttrium, zirconium and niobium induced the XPS core-line chemical shifts to higher binding-energies by 0.2-1.4 eV. In the valence-band (VB) regions, the bombardments also brought about the appearence of new photopeaks at 3.0-5.0 eV below the Fermi level. Although the peak energies are lower by 1-3 eV than those calculated for MeH2 (Me=metal) by molecular-orbital theory, the peaks are assigned to the metal-H bonds. The chemical shifts induced by bombarding hydrogen-ions were also observed in the X-ray-induced Auger electron spectra (XAES) for yttrium, zirconium and niobium. The hydride layers produced by the ion-implantation are more stable at high temperature than those obtained by thermal synthesis. The phenomena were interpreted by the surface damages which prevent thermal diffusion of hydrogen. In the case of hydrogen-ion bombarded SiC, carbon enriched layer was observed in the near surface region, while the surfaces of Si3N4 and SiO2 became silicon-rich after the bombardments. On the other hand, the bombardments of Hj, Dj and He+-ions on TiC, TiN and TiO2 made their surfaces titanium-rich. At high fluences, the X/Ti (X=C, N, O) become constant. The energy dependences of the steady state values of the C/Ti ratios have maximum at 2-4 keV/atom of incident ion, while those of the N/Ti and O/Ti ratios decreased with the increase in the ion energies. Incident-energy dependences of the Ti+/X+ ratios determined by SIMS substantiate that the sputtering is responsible for the surface compositional change of the binary compounds. The appreciable changes in the surface chemical state of TiC and TiN could not be observed after the bombardments, whereas the surface of TiO2 was easily + + reduced to Ti2O3 by the Hj and Dj, or to TiO by the He and Ar -ion bombardments, respectively. The difference in the reduced species is correlated with the thermodynamical parameters of the corresponding reduction reactions. Keywords: Surface Chemical State, Transition metal, Ceramics, Light-ion Bombardment, X-ray Photoelectron Spectroscopy, Auger Electron Spectrcscopy, Secondary ' Ion Mass Spectrometry, First Wall Material, Plasma-wall Interaction, SiC, Si,N4, SiO2,TiC,TiN,TiO2 JAER11304 JAER11304JALRI 1304 軽イオン衝撃した金属およびセラミックスの表面化学状態に関する研究 114.; IJ * Il ;i Jて}J 研究所東海研究所化学郎 11J 11J 傷付i 治 (1986W8( 1986 V 8JJ J]II 11Il受 H'JPJ!Pl! )) 要 旨 料イオン悼I 司書した金 I，~I企びセラ~ "/ケ ωl!11 1i 化 ρj': ~ IU m. を. ill (う iibl ‘により MfJiL tこ， {i>./，~"力 ンジウム.チタン.パナンウム.>i/'VA, -F ? y, Af-^j,, イ-f γ.., トリウム|- i) <•> /.,:;"'-1 レコニウ--stv^- L <•;，~びーオブに J '\O--t k ，.yォ-7'lckcVS" t-(/J - ?!J..;..t;イ > •オンを!!(¥射すると.t >£\\<\HitZ>t, XXPI' S"S x^ベヴトルのv I- ;u«i'-jiVStl 人h'i~ ヒーヴ- '/liI :t Oo 2-I2-l.4eVr.'，41.V ，:'I i， J - ネ+ b'H--illc<l;・":_fl{ lj にft ・'jIシフト司る.ま'r:>"b-t v fこ， ull j'， u ('l l:'O( ihalζIL 7 ，..1 レミレベルu.JJ、; 1) 0 :1. :i.0-5.0-5 ，00 t' t«V i~LfTfil 、> 1 ，'r.f.y.iiin に新たはヒーク均( IC ©f /"~ 'A' f- '/"^'/llfliti'liilJl する.このビー. C« ヴ 1 ，'!.i，v，'l1.う ì(・ ~i/l ìì:ï J' I!， i:命による，l!' \?M( に Jt べ 1-:j t' V lJ tL‘が . ;í}. 1，~-!J..;.A-; 帖 fT による irl j'ビーワと : 丹えられる ，!J..;.A-; イオン槽1僚にICl'Hfl;7{'j ，う化乍->"-'/7 ' トは.Mi. ~I<teW-，~イアトリウムf y I-')-V AI, :，/ •> it1レコa ιs. ウム••; A^cXl-kびニ司プの- X (:Ji! I.1J 起ォ -ý.，'，Il (Ä ベヴトルでもlI1 iaリ~ ~1 tこ目 ， ・ Ii. 金 1，~'l' にイオンiI人された 11\点/:1..熱化 "j':(， ドjにl吸泊された !J..;.A- iにlt べ 1J11熱 liklllilnll 庄が『 !?1 い.この PI!I I!は.イオン悼 1取によるj[J向山 11 ，iI， Vi が水 本の熱拡散を111111 廿るためである. 水ぷイオンifr 幣した SiC ヲーゲ y トでは.表的 iにl足止;過剰 I，Vi が形成されるが.*. Si SijN，N ,，岐び /&y'SiOSiO 2，タ 9 ーゲソ卜では.水素イオン衝喰-y-/ HTIi, <K#>f ^vflt^icft-yi'^'lζIj' ないケイ来過剰f vfiiaillfiAilfi^Sn-Sjl ，Vi が形伐される.また.. ifc, TiC. TiC. TiNTiN^^'TiO!攻リ TiO ，タ? ーゲ-y-yy 卜にHCH;H;. , 0; n; 岐び«tt>'HeHe' * イオン帽-f *y§W&Uiij' 障を1fうと. t, チタン過剰+ 9 >m%Mi)Wi8.$fLZ>.I，Vi が形成される.ぷ M(\<ny.mIf 1Iの X/Ti 比it (X;C.(X=C , N. N, 0)0)Aがー:むとなる'f¥< -VL'iySirr!KWKIc*j-i.fl(¥Q ，j ドにおいて.l"C, TiCTiC/iiftiWC/TiJt(i ;， d'I の C/Ti 比 li. 人射イオンエネルギーがAW-f * w*v*'-4(22- - - 4 ke¥' /atom の時般人;となる.AiA;i4 5. ー-/i'Ii. TiN TiN攻ぴ TiO ，J~lflÍ の X !Ti比 li. 人射イオンエネルギーの m mlfi:I'je い. qt 凋に減少する S1M3 "ベヲトルにおける Ti ‘/X ・比の人射イオンエネルギー依存判ーか ら.これら二 JI た.また.tz. itz. TiC TiCIkび TiN の表If 1I化"i':状態 li. イオン衝喉によっても変化しないが. TiO~ 先 Ir1Ï li. < H;. H;. H;, J)，イオン術慢でI>2 -f =1- ^« ^-eTiTi J，0O, ，，ICζ. , He'Hc'. Ar Mイオン * >"f*jVTTiOfriifj 隼で TiO le 3jil' JL?n£L:される.積. Wd-I隼イオン!とよるf *>IC J: S'l^l'1 成i 化学純一の 7: ;y，: li. 還JじJdt; の熱JJ 学的パラメーターと絞慌に|問辿することをI1'J'^ y - 9 - ii4?mi:IWilit 5 C i «-n/11/1 i らかに^,*»ic LI tz.た. JAERI1304 CONTENTS 1. Introduction 1 1.1 Chemical effect of energetic particle on solid surface 1 1.2 Overview of chemical state studies of ion-bombarded solid 2 1.3 Non-destructive methods for analysis of ion-bombarded solid 2 1.4 Application of XPS to chemical state analysis of ion-bambarded solid surface 3 1.5 General description of the following chapters 4 2. Core-line XPS spectra of transition metals bombarded with energetic hydrogen ions 6 2.1 Introduction 6 2.2 Experimental 6 2.2.1 Materials 6 2.2.2 Ion-implantation method 7 2.2.3 XPS measurements 9 2.3 Results and discussion 9 2.3.1 General remarks 9 2.3.2 Core-line XPS spectra of scandium II 2.3.3 Core-line XPS spectra of titanium 12 2.3.4 Core-line XPS spectra of vanadium 14 2.3.5 Core-line XPS spectra of yttrium 15 2.3.6 Core-line XPS spectra of zirconium 16 2.3.7 Core-line XPS spectra of niobium 18 2.3.8 Core-line XPS spectra of chromium, nickel and molybdenum 19 2.3.9 Dose-dependences of chemical shifts 21 2.4 Conclusions 22 3. Valence-band XPS spectra of transition metals bombarded with energetic hydrogen ions 23 3.1 Introduction 23 3.2 Experimental 23 3.3 Results and discussion 23 3.3.1 VB-XPS spectra of scandium 23 3.3.2 VB-XPS spectra of titanium 24 3.3.3 VB-XPS spectra of vanadium 26 3.3.4 VB-XPS spectra of yttrium 26 3.3.5 VB-XPS spectra of zirconium 27 3.3.6 VB-XPS spectra of niobium 29 3.3.7 VB-XPS spectra of chromium, nickel and molybdenum 30 3.3.8 Summary of chemical state of hydrogen implanted in transition metals 31 3.4 Conclusions 32 4. Thermal release of hydrogen implanted in metals 33 4.1 Introduction 33 4.2 Experimental 33 4.3 Results and discussion 34 JAERI13O4 4.3.1 Thermal release of hydrogen implanted in titanium 34 4.3.2 Thermal release of hydrogen implanted in vanadium 35 4.3.3 Thermal release of hydrogen implanted in yttrium 36 4.3.4 Thermal release of hydrogen implanted in zirconium 36 4.3.5 Thermal release of hydrogen implanted in niobium 36 4.4 Conclusions 39 5. Application of X-ray-induced Auger electron spectroscopy to state analyses of hydrogen implanted in metals 41 5.1 Introduction 41 5.2 Experimental 41 5.3 Results 41 5.4 Discussion 42 5.5 Conclusions 45 6. Surface chemical changes of SiC, Si3N4 and SiO2 by hydrogen-ion bombardments 46 6.1 Introduction 46 6.2 Experimental 46 6.2.1 Materials 46 6.2.2 Ion bombardments and measurements 46 6.3 Results 47 6.3.1 Hydrogen-ion bombarded SiC surface 47 6.3.2 Hydrogen-ion bombarded Si3N4 surface 47 6.3.3 Hydrogen-ion bombarded SiO2 surface 49 6.4 Discussion 50 6.4.1 Chemical state of ion-implanted hydrogen 50 6.4.2 Surface compositional changes by bombarding hydrogen ions 51 6.5 Conclusions 52 7.
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