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(1)

ß O

Ë  à à Šƒ » ì Å; c" e8 ý U c lT c l V R ËX ê sS  ” Ö «Y c lÊ ÝX N ËT  V R ËX ê s8 ý Ž ˜ mX N ËV R Ë; c Q V  À W ¥ „ ÇÊ Ý

"

kU £ Ó

œ

í{ © œ@ /† < Ɠ § î ß – â F g† < Æõ , Á ºî ß – 534-701

™

»< ) ç 

¸ n

q" î # Œ @ /† < Ɠ § Ó ü t o † < Æõ , " fÖ  ¦ 140-742 (2004¸   6 Z 4 3{ 9  ~ à Î6 £ §)

Cu(1,1,17) ³ ð€   0 A_  ~ à Ì} Œ • $ í  © œ\  steering ´ òõ  p u   H % ò † ¾ Ó`  ¦ kinetic Monte Carlo(KMC) r  Ó

ý

t Y Us ‚  \  moelcular dynamic(MD) r Ó ý t Y Us ‚  `  ¦   ½ + Ëô  Ç > í ß –Ü ¼– Ð “ ¦¹ 1 Ï % i  . steering\  _ K  >  é

ß –(step)   H~ ½ Ó_  7 £ x‚ Ã Ì x 9 • ¸ Ô  ¦ç  H| 9  o÷ &“ ¦ 7 £ x‚ à Ìy Œ •• ¸ _ ” > r$ í `  ¦ ˜ Ðe ” `  ¦ S X ‰ “   % i  . Õ ª   õ  7 £ x‚ à Ì" é ¶   _  { 9  y Œ •\     $ í  © œ Ô  ¦î ß –& ñ $ í \  s    z Œ ¤ . Õ ª Q  steering ´ òõ   H steering ´ òõ \  ¦ “ ¦ 9  t

 · ú §“ É r  â Ä º\  q K  ƒ  ] j  $ í  © œ Ô  ¦î ß –& ñ $ í `  ¦ 7 £ x r (   . s   H Erlich-Schwoebel Ÿ íJ $ ™[ >   © œ# 4 \  _  K

 _ … Û ¼ ~ ½ ӆ ¾ ÓÜ ¼– Ð S X ‰í ß – ¼ # † ¾ Ós   Œ •6   x # Œ, steering ´ òõ \  _ K  y © œ> é ß –(descending step)   H~ ½ Ó\  x 9

| 9  ) a 7 £ x‚ Ã Ì " é ¶  [ þ t s   © œ5 p x > é ß –(ascending step) — ¸" fo _  [  tØ  ¦  Òì  r \   8 ´ ú §“ É r f  ¨‚ à Ìs  { 9 # Q l  M : ë

 H Ü ¼– Ð  « Ñ  ) a  .

PACS numbers: 68.35.-p, 68.37.-d

Keywords:  â  ”   ³ ð€  , Steering effect, ~ à Ì} Œ • $ í  © œ

I. " e  ] Ø

Z

 }“ É r > é ß – x 9 • ¸\  ¦ ° ú   H l Ö  ¦ # Q”  (vicinal) ³ ð€   0 A\ 

~ Ã

Ì} Œ •`  ¦ $ í  © œ½ + É  â Ä º > é ß – = å Q Qo \ " f_  Schwoebel  © œ# 4  Ü

¼– Ð “   # Œ 7 £ x‚ Ã Ì " é ¶    H  © œ5 p x > é ß – ~ ½ ӆ ¾ ÓÜ ¼– Ð ˜ Ð  ´ ú §

“ É

r S X ‰í ß – S X ‰Ò  ¦`  ¦ ° ú >   ) a  . Õ ª   õ   © œ5 p x > é ß – ~ ½ ӆ ¾ ÓÜ ¼– Ð _

  Ö ¸µ 1 Ïô  Ç f  ¨‚ à ̓ É r 8 £ x â ì2 £ §(step flow) $ í  © œ`  ¦ s Ò  ¦ 0 p x$ í

`

 ¦ 7 £ x r &  l Ö  ¦ # Q”   ³ ð€  \ " f_  ~ à Ì} Œ • $ í  © œs  singular

³

ð€  \  q K   s `›   î ß –& ñ & h Ü ¼– Ð s À Ò# Qt • ¸2 Ÿ ¤ ô  Ç  [1,2].

¢

¸ô  Ç l Ö  ¦ # Q”   ³ ð€  \ " f_  q @ /g A& h  7 £ x‚ Ã Ì " é ¶  _  â ì2 £ §

“ É

r > é ß – — ¸" fo \  ¦    ½ ¨› ¸Ó ü t`  ¦ + þ A$ í r ~  ´ à º e ”   H  0

p

x$ í `  ¦ ] jr  # Œ 1 " é ¶ > _  $ í  © œ x 9 Ó ü t$ í ƒ  ½ ¨_  8 £ ¤€  \ 

"

f• ¸ Å Ò3 l q~ à Γ ¦ e ”   [3]. Õ ª Q  l Ö  ¦ # Q”   ³ ð€  \ " f ~ Ã Ì }

Œ

•`  ¦ $ í  © œr v   H  â Ä º• ¸ > é ß – — ¸" fo  ½ ¨Ô  ¦ ½ ¨Ô  ¦ K t   H

$ í

 © œ Ô  ¦î ß –& ñ $ í s    è ß –  [4–6]. s  Qô  Ç Ô  ¦î ß –& ñ & ñ $ í _ 

"

é

¶ “  Ü ¼– Ѝ  H step Erlich-Schwoebel barrier effect (SESE)

\

 _ K   l   ) a f  ¨‚ à Ì" é ¶   S X ‰í ß –_  q @ /g A$ í \  l “  ô  Ç   H Bales-Zangwill Ô  ¦î ß –& ñ $ í õ  [4,6], kink Ehrlich-Schwoebel barrier effect (KESE) \  l “  ô  Ç $ í  © œ_  Ô  ¦î ß –& ñ $ í s  [7,8]

]

jr ÷ &“ ¦ e ”   [2].

E-mail: [email protected]

0 A\  ƒ  / å L ) a î  r1 l x† < Æ& h  כ ¹™ è[ þ t s ü @\  ~ à Ì} Œ • $ í  © œ\ " f Õ

ª 1 l xî ß – Á ºr ÷ &# Q M ® o~   % i † < Æ& h  õ & ñ ×  æ  “   7 £ x‚ Ã Ì õ & ñ s

 ~ à Ì} Œ •_  $ í  © œ\  % ò † ¾ Ó`  ¦ p u   H  כ s  þ j  H[ þ t # Q S X ‰ “  ÷ &

%

3   [9]. 7 £ ¤ 7 £ x‚ Ã Ì " é ¶  ü < ³ ð€  \  $ í  © œ ) a ½ ¨› ¸Ó ü t õ _   © œ  

ñ Œ •6   x \  _ K  7 £ x‚ Ã Ì " é ¶  _  C & h s     o÷ &  H steering ´ ò õ  7 £ x‚ à Ì" é ¶   ì  r Ÿ í_  Ô  ¦ç  H| 9 `  ¦  l  “ ¦ s  כ s  ~ à Ì} Œ •

$ í

 © œ\  % ò † ¾ Ó`  ¦ p • 2 ;   H ˜ Г ¦ e ±  Ø Ô“ ¦ e ”   [9, 10].

steering ´ òõ   H Fig. 1 \ " f% ƒ! 3  7 £ x‚ Ã Ì " é ¶  ü <  © œ  ñ Œ •6   x

§

4 s   H ç  H| 9 (island) — ¸" fo  ¢ ¸  H > é ß – — ¸" fo    H~ ½ Ó\ " f

% ò

† ¾ Ó§ 4 s  ß ¼>    è ß – .   " f > é ß – x 9 • ¸ Z  }“ É r l  Ö

 ¦ # Q”   ³ ð€  \ " f_  ~ à Ì} Œ • $ í  © œ“ É r steering \  _ ô  Ç % ò † ¾ Ós  singular ³ ð€  \  q K   © œ@ /& h Ü ¼– Ð 9 þ t  כ Ü ¼– Ð \ V|  ) a  .

‘

: r ƒ  ½ ¨  H t F K  t  @ / Òì  r_  ƒ  ½ ¨\ " f Á ºr ÷ &% 3 ~   steering ´ òõ  l Ö  ¦ # Q”   ³ ð€   0 A\ " f ~ à Ì~ Ã Ì $ í  © œ\  z u 



 H % ò † ¾ Ó`  ¦ “ ¦¹ 1 Ï “ ¦    H  כ s  . 7 £ ¤ steering ´ òõ \  _

ô  Ç > é ß –   H~ ½ Ó_  7 £ x‚ à Ìx 9 • ¸(deposition flux)_  Ô  ¦ç  H| 9 $ í s

 l Ö  ¦ # Q”   ³ ð€  \ " f_  ~ à Ì} Œ •$ í  © œ\  z u   H % ò † ¾ Ó`  ¦ ˜ Ð

“

¦  ô  Ç . ¢ ¸ô  Ç 7 £ x‚ à Ì\  › ' a >   ) a % i † < Æ& h  › ¸| _  › ¸ Œ •\  _  K

" f î  r1 l x† < Æ& h  $ í  © œ Ô  ¦î ß –& ñ $ í `  ¦ F G4 Ÿ ¤½ + É 0 p x$ í s  e ”   H

\  ¦ › ¸ K  ˜ Ѐ Œ ¤ . s \  ¦ S X ‰ “   l  0 A # Œ ³ ð€   F C \ P  s

 1 p x`  ¦ “ ¦ 9½ + É € 9 כ ¹ \ O “ ¦ z  ´+ « >& h  s  : r& h  ƒ  ½ ¨   õ 

¸ ú

˜ · ú ˜ 9”   Cu(1,1,17) ³ ð€   0 A\ " f Cu " é ¶   7 £ x‚ à Ì\  @ /ô  Ç

-169-

(2)

ƒ 

½ ¨\  ¦ à º' Ÿ  % i  . ‘ : r ƒ  ½ ¨\  ¦ à º' Ÿ  l  0 A # Œ " é ¶  _  { 9

 õ & ñ `  ¦ % i † < Æ& h Ü ¼– Ð Æ Ò& h    H MD r Ó ý t Y Us ‚  õ , 7 £ x

‚ Ã

̝ ) a " é ¶  _  $ í  © œ`  ¦ — ¸    H KMC r Ó ý t Y Us ‚  `  ¦   ½ + Ë ô 

Ç ( Ž É Ó'  — ¸_  z  ´+ « >`  ¦ à º' Ÿ  % i  .

‘

: r ƒ  ½ ¨_    õ  7 £ x‚ Ã Ì y Œ •• ¸_     o\     7 £ x‚ Ã Ì x 9 • ¸ ì

 r Ÿ í    o  9, Õ ª   õ  ~ à Ì} Œ •_  $ í  © œ Ô  ¦î ß –& ñ $ í s  7 £ x‚ Ã Ì y

Œ •• ¸\  _ ” > r† < Ê`  ¦ S X ‰ “   % i  . $ í  © œ_  Ô  ¦î ß –& ñ $ í s   © œ



Œ

•“ É r 7 £ x‚ Ã Ì y Œ •• ¸ ” > r F   , s  7 £ x‚ Ã Ì y Œ •• ¸\ " f_  $ í  © œ• ¸ steering ´ òõ \  ¦ “ ¦ 9 t  · ú §€ Œ ¤`  ¦ M :˜ Ð   H Ô  ¦î ß –& ñ ô  Ç $ í



© œs  s À Ò# Qf ” `  ¦ ˜ Ð# Œ Å Ò% 3  . 7 £ ¤, steering ´ òõ   H { 9   y

Œ •• ¸ü <  © œ› ' a\ O s  Z þ t $ í  © œ_  Ô  ¦î ß –& ñ $ í `  ¦ y © œ o   H + þ AI 

–

Ð l # Œ† < Ê`  ¦ · ú ˜ à º e ” % 3  .

II. S  ö o Ú7 _T  Ó Å

~ Ã

Ì} Œ • $ í  © œõ & ñ “ É r KMC r Ó ý t Y Us ‚  `  ¦ : Ÿ x # Œ — ¸  

%

i  . : £ ¤ y  7 £ x‚ à Ìõ & ñ _  % i † < Æ& h  õ & ñ `  ¦ & ñ S X ‰ y  — ¸  l  0 AK  KMC r Ó ý t Y Us ‚   õ & ñ \ " f 7 £ x‚ Ã Ì  | s  ‚  × þ ˜÷ &€  

"

é

¶  _  & ñ S X ‰ô  Ç C & h `  ¦  z  ´& h Ü ¼– Ð — ¸  l  0 Aô  Ç MD r  Ó

ý

t Y Us ‚  s  à º' Ÿ ÷ &  H KMC r Ó ý t Y Us ‚  \  MD r Ó ý t Y Us 

‚ 

`  ¦   ½ + Ëô  Ç + þ AI \  ¦  6   x % i   [10].

MD r Ó ý t Y Us ‚  \ " f  6   xô  Ç   à º[ þ t“ É r  6 £ § õ  ° ú   . ³ ð

€ 

 " é ¶  ü < { 9   " é ¶    s _  ( J $ ™[ > “ É r Lennard Jones + þ A I

“   U (r) = 4D[(σ/r)

6

− (σ/r)

12

]\  ¦  6   x % i “ ¦, # Œl 

"

f D = 0.4093 eV s “ ¦ σ = 2.338˚ A s  . Dü < σ ° ú כ“ É r Dijken et.al._  [9,11] > í ß –   õ \  ¦ 6   x % i  . 7 £ x‚ Ã Ì " é ¶



_  œ íl  î  r1 l x \  -t   H Cu_  0 l q  H& h  “ : r • ¸\  K { © œ   H 0.15 eV – Ð ¸ ú š€ Œ ¤ . MD r Ó ý t Y Us ‚  \ " f { 9   " é ¶  _  î  r 1

l

x \  @ /ô  Ç > í ß –“ É r Velet î “ q“ ¦o 1 p u`  ¦ : Ÿ x K  ½ ¨‰ & ³ % i  . l  ó

ø Í\  7 £ x‚ à ̝ ) a " é ¶    H 7 £ x‚ Ã Ì 0 Au \ " f  © œ  î  r four-fold hollow site \  0 Au r (   . 7 £ x‚ Ã Ì f ” Ê ê ° ú > ÷ &  H ï ß –# Œ î  r 1

l

x| ¾ Ó(transient mobility)“ É r “ ¦ 9 t  · ú §€ Œ ¤ . 7 £ ¤ l ó ø Í\  7

£

x‚ Ã Ì ÷ &  H 7 £ ¤ r  l ó ø Íõ  7 £ x‚ Ã Ì " é ¶    H ¨ î + þ A © œI \  • ¸² ú ˜ 



 H  כ Ü ¼– Ð & ñ % i  .

Fig. 1. Some of the most relevant diffusion processes taken into account in the growth simulation.

Table 1. DIffusion barries considered in KMC simula- tion and other diffusion related parameters. Each diffu- sion barrrier is for the corresponding diffusion proceses illustrated in FIg. 1.

diffusion type diffusion barrier

E1 0.42 eV

E2 0.38 eV

E3 0.51 eV

E4 0.68 eV

E5 0.59 eV

E6 0.18 eV

ES E1+0.1 eV

Jump frequency(ν

0

) 3.6 × 10

12

Deposition rate (F

0

) 0.003 ML/s

KMC r Ó ý t Y Us ‚  “ É r Å Ò# Q”   fcc     0 A\ " f_  s 1 l x ë

ß –`  ¦ “ ¦ 9   H ¶ ú ˜‚ ½ Ól ^ ‰(lattice gas) — ¸+ þ A`  ¦ 2 [Ù þ ¡“ ¦, f  ¨

‚

Ã Ì " é ¶  _  S X ‰í ß –“ É r jump S X ‰í ß –ë ß –`  ¦ ) ‡6   xô  Ç . " é ¶  _  s 1 l x S X

‰Ò  ¦“ É r B í  Hç ß – — ¸Ž  H 0 p xô  Ç s 1 l x_  œ í { © œ hopping rate ν = ν

0

exp

−βE

– Ð > í ß – % i  . # Œl " f r • ¸ ‘  • ¸ ν

0

= 3.6 × 10

12

1/s – Ð ¸ ú š€ Œ ¤ . r Ó ý t Y Us ‚  \   6   x ) a S X ‰í ß –  © œ

#

4 _  & ñ _   H Fig. 1 \  [ O " î % i “ ¦, y Œ • S X ‰í ß – © œ# 4 , E,[ þ t_ 

° ú

כ“ É r Tab. I \  \ P   % i  . S X ‰í ß –  © œ# 4  ° ú כ[ þ t“ É r Koponen 1

p

x s  Cu(1,1,17) ³ ð€   0 A\ " f_  Cu 7 £ x‚ Ã Ì z  ´+ « >`  ¦ [ O " î 

% i

~   r Ó ý t Y Us ‚  \ " f  6   xô  Ç ° ú כõ  [8,12] Furmann 1 p x s  [13] Cu(001) ³ ð€  _  ~ à Ì} Œ • $ í  © œ r Ó ý t Y Us ‚  `  ¦ : Ÿ x K  % 3 “ É r

° ú

כ`  ¦ s 6   x % i  .

(1,1,17) l ó ø Í ³ ð€  “ É r ô  Ç8 £ x Z  } s _  (110)~ ½ ӆ ¾ Ó > é ß –   s

\  8.5 > h " é ¶   V , s _  (001)~ ½ ӆ ¾ Ó _ … Û ¼\  ¦ ° ú   H ³ ð€   s

 . x» ¡ ¤“ É r Fig. 1 õ  ° ú  s  > é ß – — ¸" fo ü < ¨ î ' Ÿ ô  Ç ~ ½ ӆ ¾ Ó s

“ ¦, y » ¡ ¤“ É r > é ß – — ¸" fo ü < à ºf ” “   ~ ½ ӆ ¾ ÓÜ ¼– Ð ¸ ú š€ Œ ¤ . s 

³

ð€  `  ¦ — ¸  l  0 AK , x ~ ½ ӆ ¾ ÓÜ ¼– Ð 800 a

0

_  > é ß – — ¸" f o

 U  ´s \  ¦ ° ú   H 12 > h_  _ … Û ¼– Ð s À Ò# Q”      \  ¦  6   x

% i “ ¦, x, y ¿ º ~ ½ ӆ ¾ ÓÜ ¼– Ð Å Òl & h   â > › ¸| s   Ò# Œ÷ &% 3 



.

III. + s ÇÊ Ý õ m Í À X Ø8 ý

~ Ã

Ì} Œ • $ í  © œ\  p u   H steering ´ òõ \  ¦ › ¸  l  0 A # Œ 7

£

x‚ Ã Ì y Œ •• ¸\    É r œ íl  7 £ x‚ Ã Ì x 9 • ¸\  ¦ MD – Ð > í ß – % i  .

7

£

x‚ à Ì" é ¶  ü < l ó ø Í" é ¶    s _   © œ  ñ Œ •6   x \  _ ô  Ç steering

´

òõ – Ð { 9  " é ¶  _  C & h s  > é ß –   H % ƒ\ " f è  H \  ` (>  6 f

#

Qt   H  כ `  ¦ ^  ¦ à º e ”  .(Fig. 2(a)(b)) y Œ •• ¸\    É r 0 Au  Z >

 7 £ x‚ Ã Ì x 9 • ¸  H Fig. 2c-g \  ˜ Ð# Œ Šғ ¦ e ”  . y Œ •• ¸  H >  é

ß –  s _  (0,0,1) _ … Û ¼\  à ºf ” “   ~ ½ ӆ ¾ Ó\  @ /ô  Ç y Œ •• ¸– Ð,

(3)

Fig. 2. Trajectories of depositing atoms (a-b) and flux distributions (c-h). Depsoition angles: a) −70

o

, (b)+70

o

, (c) −70

o

, (d)+70

o

, (e) −35

o

, (f)+35

o

, (g) 0

o

. (h) Deposition without taking the steering effect into account. Solid circle : deposition flux. open cir- cle : deposition flux after subtracting excess flux due to reduced adsorption sites near step edge. (See main text for detail.)

-y Œ •• ¸  H Fig. 2(a) ü < ° ú  s  ± ú “ É r > é ß –\ " f Z  }“ É r > é ß – ~ ½ ӆ ¾ Ó Ü

¼– Ð l Ö  ¦ # Q4 R 7 £ x‚ à Ì" é ¶   { 9     H  â Ä ºs  9, +y Œ •• ¸  H Õ

ª ì ø Í@ /– Ð { 9     H  â Ä ºs  .

f

 ¨‚ à Ì" é ¶  _  0 Au Z >  7 £ x‚ à Ìx 9 • ¸  H Fig. 2(c-g) ü < ° ú  s  >  é

ß –   H~ ½ Ó\ " f x 9 • ¸ Z  }  ”   . Õ ª Q  s  > é ß –   H~ ½ Ó_  Z  }

“ É

r 7 £ x‚ à Ìx 9 • ¸ ì  r Ÿ í steering ´ òõ ë ß –\  _ K " f + þ A$ í  ) a  כ

“ É

r  m  . Fig. 2(h)  H steering ´ òõ  “ ¦ 9÷ &t  · ú §“ ¦ 7

£

x‚ à Ì" é ¶  \  ¦ Á º Œ •0 A– Ð Í Ò 2 ;  â Ä º_  7 £ x‚ Ã Ì x 9 • ¸s  . Fig.

2(h) ü < ° ú  s  steering ´ òõ \  ¦ “ ¦ 9 t  · ú §“ ¦ Á º Œ •0 A– Ð 7 £ x

‚

à Ìr & • ¸ > é ß –   H~ ½ Ó\ " f  © œ@ /& h Ü ¼– Ð Z  }“ É r 7 £ x‚ Ã Ì x 9 • ¸\  ¦

”   . s  כ “ É r Fig. 2(h) \  ˜ Ð# Œ”    כ % ƒ! 3  > é ß – — ¸" fo 



 H~ ½ Ó 2.5 a

0

 o  î ß –\  7 £ x‚ Ã Ì 0 p xô  Ç 0 Au   H 2 > h µ 1 Ú\  î ß –

÷

&  H 7 £ x‚ Ã Ì 0 p xô  Ç 0 Au _    ’ < H M :ë  H s  . s ü < ° ú  “ É r 7 £ x

‚ Ã

Ì 0 Au _    ’ < H \  _ ô  Ç כ ¹“  `  ¦ ] j  # Œ• ¸ Fig. 2_  \ P 



2 ; " é ¶ % ƒ! 3  steering ´ òõ \  _ ô  Ç > é ß – — ¸" fo    H~ ½ Ó_  7 £ x

‚

à Ìx 9 • ¸ 7 £ x   H   è ß – .

7

£

x‚ Ã Ì y Œ •• ¸ l Ö  ¦ # Q| 9  à º2 Ÿ ¤(Fig. 2(c,e)) 7 £ x‚ à Ìx 9 • ¸_ 

>

é ß – — ¸" fo    H~ ½ Ó_  x 9 | 9  & ñ • ¸ d ” K t   H  כ `  ¦ ^  ¦ à º e ”

 . s  כ “ É r 7 £ x‚ Ã Ì y Œ •• ¸ d ”  >  l Ö  ¦ # Q| 9  à º2 Ÿ ¤ 7 £ x‚ à Ì" é ¶



ü < l ó ø Í s _   © œ  ñ Œ •6   x r ç ß –s  U  ´# Q4 R steering\  _  ô 

Ç ´ òõ  7 £ x  l  M :ë  H s  . ô  Çt  < É ª p – Ðî  r  z  ´“ É r 7

£

x‚ Ã Ì y Œ •• ¸ +y Œ •“    â Ä º(Fig. 2(d,f))ü < -y Œ •“    â Ä º(Fig.

3(c,e)) ü <_  s s  . ± ú “ É r A á ¤ \ " f Z  }“ É rA á ¤ Ü ¼– Ð { 9   



 H -y Œ •_   â Ä º  © œ5 p x > é ß –(ascending step)   H~ ½ Ó_  7 £ x‚ à ÌS X ‰ Ò

 ¦ s  y © œ> é ß –(descending step)   H~ ½ Ә Ð   H ì ø ̀  (Fig.

2(c,e)), Õ ª ì ø Í@ /“   +y Œ •Ü ¼– Ð { 9     H  â Ä º, y © œ> é ß –   H

~

½ Ó_  7 £ x‚ Ã Ì S X ‰Ò  ¦ s   © œ5 p x > é ß –   H~ ½ Ó ˜ Ð  Z  }6 £ §`  ¦ · ú ˜ à º e ” 



.

¨ î

ç  H 7 £ x‚ à Ìx 9 • ¸ü < q “ §ô  Ç > é ß –\  “  ] X ô  Ç 3> h site\  @ / ô 

Ç ¨ î ç  H 7 £ x‚ à Ìx 9 • ¸\  ¦ (∆f ) ˜ Ѐ   (Table II) +70

o

– Ð { 9   ô 

Ç  â Ä º  © œ5 p x > é ß –   H~ ½ Ó_  7 £ x‚ à Ìx 9 • ¸(∆f

D

)  H y © œ> é ß –   H

~

½ Ó_  ¨ î ç  H 7 £ x‚ à Ìx 9 • ¸(∆f

U

)_  86%\  Ô  ¦ õ † < Ê`  ¦ ^  ¦ à º e ” 



. Õ ª Q  \ Vü @& h Ü ¼– Ð ∆f

D

  H -35 • ¸– Ð 7 £ x‚ à Ìô  Ç  â Ä º

\

 ¦ ] jü @ “ ¦ @ / Òì  r_  7 £ x‚ Ã Ì y Œ •• ¸\ " f ∆f

D

 ∆f

U

˜ Ð 



Œ

•6 £ §`  ¦ ^  ¦ à º e ”  . s  כ “ É r Fig. 2(b) \  ˜ Ðs   H  כ õ  ° ú  s 

€

ª œ_  y Œ •• ¸_   â Ä º steering ´ òõ \   8 # Œ ` ‚(blocking)

´

òõ  > é ß –  A A á ¤ \  7 £ x‚ à Ì" é ¶   b  # Qt   H  כ `  ¦ } Œ •  H ì

ø ̀   - y Œ •• ¸_   â Ä º  H(Fig. 2(a)) › ¸   ) a 7 £ x‚ à Ìy Œ •• ¸ ? /\ 

"

f  H ` ‚ ´ òõ \  ¦  _  ~ à Ît  · ú §l  M :ë  H Ü ¼– Ð  « Ñ  ) a  .

Steering ´ òõ \  _ ô  Ç 7 £ x‚ à Ìx 9 • ¸_  ì  rç  H{ 9 õ  7 £ x‚ à Ìy Œ •• ¸ _

” > r$ í s  ~ à Ì} Œ • $ í  © œ\  p u   H % ò † ¾ Ó`  ¦ ¶ ú ˜( R˜ Ðl  0 A # Œ 7

£

x‚ Ã Ì y Œ •• ¸\  ¦    o r &  9 ~ à Ì} Œ • $ í  © œ r Ó ý t Y Us ‚  `  ¦ à º '

Ÿ Ù þ ¡ . r Ó ý t Y Us ‚  “ É r steering ´ òõ \  ¦ “ ¦ 9ô  Ç 7 £ ¤ MD\  ¦ KMC r Ó ý t Y Us ‚  \    ½ + Ër †   á Ԗ ÐÕ ªÏ þ ›s  . s 6   xô  Ç S X ‰ í

ß –  © œ# 4 “ É r Table I õ  ° ú  “ ¦, l ó ø Í “ : r • ¸  H 240 K s  . r Ó ý t Y

Us ‚     õ – Ð % 3 “ É r ³ ð€  _  Û ¼è ­ s Õ ªa Ë >“ É r Fig. 3(a)(b) ü <

°

ú   . Fig. 3(c)  H 7 £ x‚ à Ì| ¾ Ó 7 £ x \    É r e ” _ _  ô  Ç > é ß –

—

¸" fo _  $ í  © œ õ & ñ `  ¦ ˜ Ð# Œï  r  . > é ß – — ¸" fo _  ¨ î ç  H 0 A u

 1 MLm ”  7 £ x‚ à Ì| ¨ c M : _ … Û ¼ ç ß –  “   8.5 a

0

m ”  ”  ' Ÿ 

# Œ  _  8 £ x â ì2 £ §(step flow) $ í  © œ + þ AI \   î  r $ í  © œs  s

À Ò# Q f ” `  ¦ · ú ˜ à º e ”  . Õ ª Q  > é ß –õ  à ºf ” “   ~ ½ ӆ ¾ ÓÜ ¼

–

Ð  } 9 l  7 £ x‚ à Ì| ¾ Ó 7 £ x \     & h   7 £ x  “ ¦ e ” 6 £ §`  ¦

^

 ¦ à º e ”  . ¢ ¸ô  Ç 7 £ x‚ à Ì| ¾ Ós  7 £ x † < Ê\     “  ] X ô  Ç _ … Û ¼

\

 $ í  © œ   H > é ß – — ¸" fo [ þ t  s _    ´ ú 6 £ § s  7 £ x  # Œ

’finger’-+ þ AI _  ½ ¨› ¸ + þ A$ í H † d • ¸ ^  ¦ à º e ”  (Fig. 3(c)).



Œ

™y Œ •+ þ A — ¸€ ª œ_  > é ß – — ¸" fo   H z  ´+ « >\ " f [6] › ' a8 £ ¤ ) a $ í  © œ + þ

AI ü < 1 l x{ 9   9, 0 A_  r Ó ý t Y Us ‚     õ   H Cu(1,1,17) €   0 A\  Cu " é ¶  \  ¦ 7 £ x‚ à Ìô  Ç Koponen_  [8] r Ó ý t Y Us ‚     õ  ü

<• ¸ q 5 p w  .

Table 2. ∆f

U

(∆f

D

) : Mean deposition flux averaged over three sites from descending step edge. NS: No steer- ing is taken into account.

angle -70

o

-35

o

0

o

+35

o

+70

o

NS

∆f

U

+6.1 % +2.2 % +4.2 % +8.2 % +12.9 % +2.0 %

∆f

D

+5.2 % +4.4 % -0.1 % -5.8 % -8.9 % +2.0 %

(4)

Fig. 3. Snap shots after depositing 5 ML of CU on Cu(1,1,17) at 240 K. (a) No steering effect is taken into account. (b) Deposition angle, 70

o

. (c) Evolution of a step edge till depositing 5 ML by 1/3 ML increment.

SIze of figures: (a)(b) 800 ×152 a

20

, (c) 800 ×54 a

02

. a

0

means the surface lattice constant of Cu(001).

$ í

 © œ_  Ô  ¦î ß –& ñ $ í `  ¦ & ñ | ¾ Ó& h Ü ¼– Ð l Õ ü t l  0 A # Œ $ í  © œ

 )

a ~ à Ì} Œ •_  morphology_  ' ‘ • ¸– Ð €  ~ ½ ӆ ¾ Ó  } 9 l (lateral roughness) ü < t ; Ÿ ¤(finger width)\  ¦ › ¸  % i  . 7 £ x‚ à Ì

l  „   > é ß – — ¸" fo _  y Œ • 0 Au  x\ " f growth front  t

_  Z  } s (— ¸" fo ü < à ºf ” “   ~ ½ ӆ ¾ Ó_  U  ´s )\  ¦ h(x)   

€ 

, €  ~ ½ ӆ ¾ Ó  } 9 l  w = √

< h

2

− < h >

2

> – Ð & ñ _  % i 



. t ; Ÿ ¤“ É r y Œ • > é ß –_  ¨ î ç  H – л ¡ ¤Z  } s (lateral height)

±5a

0

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% i  . 7 £ x‚ à Ì| ¾ Ó_  7 £ x @ /\    É r 0 A_  y Œ • | ¾ Ó[ þ t_  > í ß –    õ

\  ¦ Fig. 4 \    Í Ç x .

€ 

~ ½ ӆ ¾ Ó } 9 l (Fig. 4(a))\  ¦ ˜ Ѐ   7 £ x‚ à Ì| ¾ Ós  7 £ x † < Ê\ 



   } 9 l  7 £ x † < Ê`  ¦ ^  ¦ à º e ”  . þ j@ / 5 ML\  ¦ 7 £ x‚ à Ì

% i `  ¦ M :  } 9 l  ° ú כ“ É r €  • 7a

0

– Ð  • 2 ; growth front\  ¦ + þ A

$ í

† < Ê`  ¦ · ú ˜ à º e ”  . Fig. 4(a) inset– Ð ^  ¦ M : 7 £ x‚ Ã Ì y Œ •• ¸

0 • ¸  -35• ¸_   â Ä º  } 9 l   © œ  Œ •“ ¦ +70• ¸“    â Ä º

 © œ  H ° ú כ`  ¦ ˜ Ðe ” `  ¦ S X ‰ “  ½ + É Ã º e ”  . 7 £ x‚ à Ì| ¾ Ó 7 £ x \   

 É

r t ; Ÿ ¤_     o• ¸ (Fig. 4(b)), €  ~ ½ ӆ ¾ Ó } 9 l _  { 9  y Œ • _

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˜

Ðs   H -35 • ¸ 7 £ x‚ à Ì_   â Ä º  H t ; Ÿ ¤ ° ú כ`  ¦ [14] ˜ Ðs “ ¦, 7

£

¤ î ß –& ñ  ) a 8 £ x â ì2 £ § $ í  © œ + þ AI \  ¦ ˜ Ðs “ ¦ e ” Ü ¼ 9, ì ø ̀     } 9

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£

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 É

r $ í  © œ_  Ô  ¦î ß –& ñ $ í õ  7 £ x‚ à Ìx 9 • ¸ ì  r Ÿ í\  ¦ q “ §K ˜ Ѐ   { 9 

&

ñ ô  Ç  ⠆ ¾ Ó`  ¦ ° ú 6 £ §`  ¦ · ú ˜ à º e ”  . Table II\ " f y © œ> é ß –



 H~ ½ Ó_  7 £ x‚ à Ìx 9 • ¸  © œ  H +70 • ¸_   â Ä º, $ í  © œ_  Ô  ¦î ß –

&

ñ $ í s   © œ ß ¼“ ¦, Õ ª ì ø Í@ /_   â Ä º“   -35• ¸– Ð 7 £ x‚ à Ìô  Ç  â Ä

º,  © œ@ /& h Ü ¼– Ð  © œ î ß –& ñ  ) a $ í  © œs       H  כ `  ¦ ^  ¦ à º e ”

 . (Fig. 4)

y © œ > é ß –   H~ ½ Ó_  " é ¶    H Schwoebel  © œ# 4 _  % ò † ¾ ÓÜ ¼– Ð



A  _ … Û ¼– Ð y © œ l  # Q§ >  .   " f y © œ > é ß –   H

~

½ Ó\  7 £ x‚ à ̝ ) a " é ¶    H _ … Û ¼ A á ¤ Ü ¼– Ð S X ‰í ß –| ¨ c S X ‰Ò  ¦ s  Z  } “ ¦,

Fig. 4. (a) lateral roughness and (b) finger width (lat- eral coarseness) for morphologies after depositing 5ML CU on Cu(1 1 17) at 240K. See main text for detailed description on the definition of the lateral roughness and the finger width. NS: Steering is not taken into account.

Õ

ª õ & ñ ×  æ  © œ5 p x > é ß –_  [  tØ  ¦ ) a — ¸" fo   Òì  r \  f  ¨‚ à Ì| ¨ c S X ‰ Ò

 ¦ s   © œ@ /& h Ü ¼– Ð Z  }   growth front_  Ô  ¦ç  H| 9 ô  Ç $ í  © œ\  l

# Œ >  | ¨ c  כ s  .   " f Table 2_  7 £ x‚ à Ìx 9 • ¸ r Ó ý t Y U s

‚     õ \ " f ˜ Ð1 p w y © œ> é ß –   H~ ½ Ó_  œ íl  7 £ x‚ à Ìx 9 • ¸

9 þ

t à º2 Ÿ ¤ $ í  © œ_  Ô  ¦î ß –& ñ $ í s  7 £ x    H  כ `  ¦ µ 1 Ï|  >   ) a



.

Fig. 4\  ¦ ˜ Ѐ  , steering`  ¦ ´ òõ \  ¦ “ ¦ 9ô  Ç  â Ä º  H y Œ •• ¸ ü

< Á º › ' a >  ƒ  ] j  steering ´ òõ \  ¦ Á ºr ô  Ç  â Ä º(Fig. 4,

  H & h ‚  )\  q K  €  ~ ½ ӆ ¾ Ó } 9 l  7 £ x  “ ¦ t ; Ÿ ¤“ É r



Œ • t   H   õ \  ¦ ^  ¦ à º e ”  . 7 £ ¤ steering ´ òõ  ƒ  ] j 

$ í

 © œ_  Ô  ¦î ß –& ñ $ í `  ¦ y © œ o   H ~ ½ ӆ ¾ ÓÜ ¼– Ð l # Œ† < Ê`  ¦ · ú ˜ à º e ”

 . ‘ : r r Ó ý t Y Us ‚  \ " f steering ´ òõ   H 7 £ x‚ à Ìx 9 • ¸\ ë ß –

% ò

† ¾ Ó`  ¦ p u Ù ¼– Ð, steering\  _ K  y © œ o ) a $ í  © œ_  Ô  ¦î ß –& ñ

$ í

“ É r 7 £ x‚ à Ìx 9 • ¸_  Ô  ¦ç  H| 9 \    É r % ò † ¾ Ós  . Table II\  ¦ ˜ Ð

€ 

 steering`  ¦ “ ¦ 9ô  Ç — ¸Ž  H y Œ •• ¸\ " f y © œ> é ß –   H~ ½ Ó_  7 £ x

‚

à Ìx 9 • ¸ steering`  ¦ Á ºr ô  Ç  â Ä º˜ Ð  Z  }“ É r  כ `  ¦ ^  ¦ à º e ” 



.   " f steering\  _ ô  Ç $ í  © œ Ô  ¦î ß –& ñ $ í _  y © œ o  H, $ í



© œ Ô  ¦î ß –& ñ $ í _  7 £ x‚ à Ìy Œ •• ¸ _ ” > r$ í _  [ O " î õ  ° ú  s , y © œ>  é

ß –   H~ ½ Ó\  7 £ x‚ à Ìx 9 • ¸ 7 £ x @ /† < Ê\  l “  ô  Ç “ ¦ ½ + É Ã º e ”  .

(5)

IV. + s Ç Â ] Ø õ m Í ~ ¿W d l

7

£

x‚ Ã Ì " é ¶   l ó ø Í " é ¶  ü <_   © œ  ñ Œ •6   x \  _ K  { 9   C

&

h s  % ò † ¾ Ó`  ¦ ~ à ΍  H steering ´ òõ  Cu(1,1,17) ³ ð€   0 A\ 

"

f ~ à Ì} Œ • $ í  © œ\  z u   H % ò † ¾ Ó`  ¦ KMC r Ó ý t Y Us ‚  \  MD r

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\

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“ É

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

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`

 ¦ 7 £ x r (   . s   H Erlich-Schwoebel  © œ# 4 \  _ K  _ …  Û

¼ ~ ½ ӆ ¾ ÓÜ ¼– Ð S X ‰í ß – ¼ # † ¾ Ós   Œ •6   x # Œ, steering ´ òõ \  _  K

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“

   כ Ü ¼– Ð  « Ñ  ) a  

V. P c p 8 ý ò k >

‘

: r  7 Hë  H“ É r ¸ n q" î # Œ  @ /† < Ɠ § 2003¸  • ¸ “ §? / ƒ  ½ ¨q  t 

"

é

¶ \  _ K  à º' Ÿ ÷ &% 3 6 £ §.

Y c

p w Š à U Ø ”  ô

[1] M. D. Johnson, C. Orme, A. W. Hunt, D. Graff, J.

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Politi, Phys. Rev. Lett. 80, 4221(1998); O. Pierre- Louis, M. R. D’Orsogna and T. L. Einstein, Phys.

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[14] The finger width is defined as the average seper- ation between adjacent fingers taken over ± 5 a

0

from mean height., In the early stage of growth, the

fingers are well discernable, and the finger width is

anomalously large.

(6)

Steering Effects on Growth Instability During Step-Flow Growth of Cu on Cu(1,1,17)

Jikeun Seo

Division of General Education, Chodang University, Muan 534-701

J.-S. Kim

Department of Physics, Sook-Myung Women’s University, Seoul 140-742 (Received 3 June 2004)

A kinetic Monte Carlo simulation, in conjunction with a molecular dynamics simulation, is used to study the effect of steered deposition on the thin film growth of Cu on Cu(1,1,17). The deposition flux is found to become inhomogeneous in the step train direction when the deposition is made along that direction. The inhomogeneity depends on the deposition angle, and the steering effect always increases the growth instability in the case of a homogeneous deposition. The growth instability depends on the deposition angle and direction, showing a minimum at a certain deposition angle off-normal to the (001) terrace, and it has a strong correlation with the inhomogeneous deposition flux. The increase in the growth instability may be explained as follows: At the descending step edge, there is diffusion bias toward ascending step edge driven by Erlich Schwoebel barrier. Steering effect enhances deposition flux near descending step edge and these increased number of deposit atoms are likely to adhere to the protruding parts of ascending step edges during terrace diffusion, resulting larger meandering growth instability.

PACS numbers: 68.35.-p, 68.37.-d

Keywords: Vicinal surface, Steering effect. Thin film growth

E-mail: [email protected]

수치

Fig. 1. Some of the most relevant diffusion processes taken into account in the growth simulation.
Fig. 2. Trajectories of depositing atoms (a-b) and flux distributions (c-h). Depsoition angles: a) −70 o , (b)+70 o , (c) −70 o , (d)+70 o , (e) −35 o , (f)+35 o , (g) 0 o
Fig. 3. Snap shots after depositing 5 ML of CU on Cu(1,1,17) at 240 K. (a) No steering effect is taken into account

참조

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