CF 4 /CH 4 -TCPCVD U ê s0 n É; c 8 ý” X ¢ $ [– ¥ ¹ ÅV ê s• ¤õ u § P c t À W ¥ a-C : FU c lT c l ] k ùV R Ë; c 6 ” X ¢ Ž ì ŏ Œ

CF ₄ /CH ₄ -TCPCVD U ê s0 n É; c 8 ý” X ¢ $ [– ¥ ¹ ÅV ê s• ¤õ u § P c t À W ¥ a-C : FU c lT c l ] k ùV R Ë; c 6 ” X ¢ Ž ì ŏ Œ



™ »%
¬ £

]

jÅ Ò@ /† < Ɠ §  ƒ  õ † < Æ@ /† < Æ  o† < Æõ , ] jÅ Ò 690-756

z

‡ Ú+ ä  · L |V ¦  ^∗

]

jÅ Ò@ /† < Ɠ §  ƒ  õ † < Æ@ /† < Æ Ó ü t o † < Æõ , ] jÅ Ò 690-756 (2005¸   1 Z 4 5{ 9  ~ à Î6 £ §)

a-C : F ~ à Ì} Œ •“ É r CF

4

/CH

4

™ D ¥ ½ + ËÛ ¼\  ¦  6   x # Œ transformer coupled plasma chemical vapor depo- sition (TCPCVD) ~ ½ ÓZ O Ü ¼– Ð l ó ø Í Si(100) 0 A\  + þ A$ í r (   . a-C:F ~ à Ì} Œ •\ " f C-F, C-F

²

, C-F

3

, C=CF

2

Õ

ªo “ ¦ CF=CF

2

bond 1 p x \  @ /ô  Ç   ½ + ˽ ¨› ¸\  ¦ Ÿ í† < Ê “ ¦ e ” 6 £ §`  ¦ Fourier transformation infrared spec- troscopy ü < X-ray photoelectron spectroscopy– Ð ì  r$ 3  % i  . rf power 600 W\ " f (F/C) " é ¶ ™ è_  0

l

x • ¸q  €  • 1.8– Ð þ j@ /_  ° ú כ`  ¦ ˜ Ð% i Ü ¼ 9, + þ A$ í  ) a a-C:F ~ à Ì} Œ •“ É r C-F

2

, C-F

3

, CF

3

-CF

2

, C=CF

2

Õ ªo 

“

¦ CF=CF

2

1 p x _  bond– Ð + þ A$ í  ) a F " é ¶ ™ è-õ   C-F

x

  ½ + ˽ ¨› ¸\  ¦
 ? /% 3  .  © œ ± ú “ É r Ä »„   © œÃ ºü <

Ï

ã J] X Ò  ¦“ É r rf power  600 W\ " f + þ A$ í  ) a ~ à Ì} Œ •s  1.6õ  1.4– Ð Å Ò# Q& ’  .   " f a-C:F ~ à Ì} Œ •_  Ä »„   © œ Ã

º  H (F/C) " é ¶ ™ è_  0 l x • ¸q \  _ ” > r “ ¦, rf power\     a-C:F

x

  ½ + ˽ ¨› ¸    o H † d`  ¦ ˜ Ð% i  .

PACS numbers: 77.22.-d, 77.55.+f, 77.84.-s

Keywords: Ä »„   © œÃ º, 8 £ x ç ß –] X ƒ  } Œ •, q & ñ | 9 Ô  ¦ ™ è oò ø ͙ è, $ Ä »„  ~ à Ì} Œ •,   ½ + ˽ ¨› ¸

I. " e  ] Ø

œ

í“ ¦| 9 & h (ULSI: ultralarge scale integration) ™ è   H J

‡  _  p [ j o, | 9 & h • ¸ 7 £ x , “ ¦5 Å q  o, Õ ªo “ ¦ p [ j o H † d

\

    C ‚  ç ß –  s  0.13 µm s  – Ð y Œ ™™ è÷ &“ ¦ e ”  . ‰ & ³ F

  6   x ÷ &“ ¦ e ”   H SiO

2

8 £ x ç ß – ] X ƒ  } Œ •`  ¦  6   x   H  â Ä º, l  Ò q

t& ñ „  6   x | ¾ Ó_  µ 1 ÏÒ q t\  _  # Œ ™ è _  ’    ñ t ƒ  , power dissipation Õ ªo “ ¦ ¸ ú š6 £ §1 p x`  ¦ { 9 Ü ¼†   . s ü < ° ú  “ É r ë  H ] j

&

h

`  ¦ K ™ è l  0 A # Œ Al (ρ = 2.66 µΩ·m) C ‚  `  ¦ q $ 

†

½ Ós  ± ú “ É r Cu (ρ = 1.65 µΩ·m) C ‚  Ü ¼– Ð    ⠍  H  כ õ

 ‰ & ³F   6   x ÷ &“ ¦ e ”   H SiO

2

8 £ x ç ß – ] X ƒ  } Œ •`  ¦ Ä »„   © œÃ º

3.0 s  “   $ Ä »„   Ó ü t| 9 – Ð @ /^ ‰   H  כ s  . l ” > r _  8 £ x ç

ß – ] X ƒ   Ó ü t| 9 “   SiO

2

  H ~ à Ì} Œ •_  ¨ î ò ø Í o : £ ¤$ í s  8 A# Q
t  ë

ß – é ß –  x 4 Ÿ ¤$ í s 
å ԓ ¦, 3.0 ∼ 4.2 & ñ • ¸_  Z  }“ É r Ä »„   © œ Ã

º\  ¦ t “ ¦ e ” # Q" f ™ è _  “ ¦| 9 & h  oü < “ ¦5 Å q  o 1 p x _  › ¸

|

`  ¦ Ø  æ7 á ¤ r v l  ' p  Ò7 á ¤  .   " f Ä »„   © œÃ º 3.0 s 

“   8 £ x ç ß – ] X ƒ   Ó ü t| 9 \  @ /ô  Ç ´ ú §“ É r ƒ  ½ ¨ ] X z  ´y  כ ¹½ ¨

÷

&“ ¦ e ”  . s  Qô  Ç $ Ä »„   ~ à Ì} Œ •\   H XLK, SiLK,  / B N$ í

∗

E-mail: [email protected]

SiLF, SiOF, nano-pore ½ ¨› ¸\  ¦ ° ú   H SiOC(-H), Õ ªo “ ¦ fluorinated amorphous carbon(a-C:F) ~ à Ì} Œ • 1 p x s  e ”  .

$

Ä »„    © œÃ º\  ¦ ° ú   H ~ à Ì} Œ • ×  æ \ " f a-C:F ~ à Ì} Œ •“ É r ò ø Í o Ô  ¦

™

è “ ¦ì  r  – Ð   ½ + Ë # Œ PTFE (polytetrafluoro ethylene)

½

¨› ¸– Ð 2.0 & ñ • ¸_  $ Ä »„   © œÃ ºü < Chemical Mechanical Polishing (CMP) / B N& ñ \ " f l > & h  : £ ¤$ í s  Ä ºÃ º “ ¦, y © œ ô

 Ç ] X ‚ à ̧ 4 , \ P & h  î ß –& ñ $ í (>400

^◦

C), „  l & h ,  o† < Æ& h  : £ ¤

$ í

õ  ± ú “ É r OH f  ¨ à º– Ð  © œ Ä ºÃ ºô  Ç ] X ƒ  } Œ •Ü ¼– Ð @ /¿ º÷ &

#

Q Cu/Low-κ ™ è _  8 £ x ç ß – ] X ƒ  Ó ü t| 9 – Ð & h 6   x 0 p x$ í s  ]

jr ÷ &“ ¦ e ”   [1–6].  =
 €   F " é ¶    H Z  }“ É r „  l 6 £ §

$ í

• ¸(4.2)ü < ± ú “ É r ì  rF GÒ  ¦(0.557)`  ¦ ° ú “ ¦ e ” l  M :ë  H \  C- F

2

  ½ + Ës  ~ 1 >  s À Ò# Q”   . { 9 ì ø Í& h Ü ¼– Ð a-C:F ~ à Ì} Œ •“ É r CF

4

, C

2

F

6

x 9  C

₄

F

8

1 p x _  Ô  ¦ ™ è o½ + ËÓ ü t`  ¦ CH

4

Û ¼ü < ™ D ¥

½

+ Ë # Œ PECVD (plasma enhanced chemical vapor depo- sition) ~ ½ ÓZ O Ü ¼– Ð + þ A$ í ÷ &“ ¦ e ”  . PECVD ~ ½ ÓZ O \   H CCP (capacitavely coupled plasma), ICP (inductively coupled plasma) [7,8], TCP (transformer coupled plasma), Heli- con Plasma [9] 1 p x _  e  ¦  Ý ¼ -" é ¶`  ¦  6   x “ ¦ e ”  . e  ¦



Ý ¼ -" é ¶ ×  æ \ " f TCP-" é ¶`  ¦  6   x €   10

¹¹



⁻³

s  © œ_ 

“

¦x 9 • ¸ e  ¦  Ý ¼ \  ¦ % 3 `  ¦ à º e ” “ ¦, precursor\  ¦ Ø  æì  r y  K 

-93-

o

r & " f ~ à Ì} Œ • + þ A$ í \  € 9 כ ¹ô  Ç radical`  ¦ Ò q t$ í r ~  ´ à º e ”  Ü

¼Ù ¼– Ð crosslink ½ ¨› ¸\  ¦ ”   u x 9 ô  Ç ~ à Ì} Œ •+ þ A$ í s  0 p x 



.

‘

: r ƒ  ½ ¨\ " f  H CH

4

ü < CF

⁴

\  ¦ precursor – Ð  6   x 

#

Œ TCPCVD ~ ½ ÓZ O Ü ¼– Ð a-C:F ~ à Ì} Œ •`  ¦ + þ A$ í % i  . + þ A

$ í

 ) a a-C:F ~ à Ì} Œ •_    ½ + ˽ ¨› ¸  H FTIR (Fourier trans- form infrared) ü < XPS (X-ray photoelectron spec- troscopy)\  ¦ s 6   x # Œ ì  r$ 3  % i “ ¦, Ï ã J] X Ö  ¦ õ  7 £ x ‚ à ÌÖ  ¦“ É r ellipsometry ü < Field emission scanning electron mi- croscopy (FESEM) – Ð › ¸  % i  . „  l & h  : £ ¤$ í “ É r MIS (metal/insulator/semiconductor; Al/a-C:F/p-Si(100))

½

¨› ¸\ " f C-V\  ¦ s 6   x # Œ Ä »„   © œÃ º\  ¦ › ¸  % i  .

II. ÷ m Ç] M öU ê s0 n É

‘

: r z  ´+ « >\ " f a-C:F ~ à Ì} Œ •+ þ A$ í \   6   x ô  Ç TCPCVD  © œ u

\ " f  H ì ø Í6 £ x – Ð, î ß –_ …
, rf „  " é ¶ Ü ¼– Ð ½ ¨$ í  ) a ì ø Í6 £ x  Òü <

Dry/Booster * 3 á Ԗ Ð ½ ¨$ í  ) a ”  / B N C l Â Ò Õ ªo “ ¦ ì ø Í6 £ x  Û

¼\  ¦ Å Ò{ 9 r & Šҍ  H Û ¼ Å Ò{ 9  Җ Ð ÷ &# Qe ”  . Û ¼_  Ä »

|

¾ ӛ ¸] X “ É r MFC (mass flow controller) – Ð ] j# Q • ¸2 Ÿ ¤ 

%

i “ ¦, Ä »| ¾ Ó\    É r ”  / B N • ¸  H throttle valve \  _  # Œ   1

l

x Ü ¼– Ð ] j# Qž Ð2 Ÿ ¤ % i  . ”  / B N • ¸ 8 £ ¤& ñ “ É r baratron > s  t

– Ð 8 £ ¤& ñ % i  . 13.56 MHz Å Ò à º\  ¦ ° ú   H rf power  H þ

j@ / 1.2 kW_  Ø  ¦§ 4 `  ¦ ƒ  5 Å q& h Ü ¼– Ð è ­ q à º e ”   H  © œu \  ¦   6

 

x % i  . rf power  H 400 W \ " f 800 W t     o €  " f z 

´+ « >`  ¦ % i  . rf_  ì ø Í    H y Œ • Ø  ¦§ 4 \ " f    6   x | ¾ Ól 

\

 ¦    or v €  " f › ¸] X  % i   H X < y Œ • Ø  ¦§ 4 \  @ /K  ì ø Í  

 5 % s ? /\  [ þ t • ¸2 Ÿ ¤ e ” x ~  Û ¼\  ¦ ´ ú Æ Ò# Q €  " f z  ´+ « >

`

 ¦ % i  . a-C:F ~ à Ì} Œ •+ þ A$ í \   6   x ô  Ç ì ø Í6 £ x Û ¼  H CH

4

ü <

CF

₄

\  ¦  6   x % i  . s  M : ì ø Í6 £ x – Ð\  Å Ò{ 9 ÷ &  H CH

4

ü < CF

4

Û ¼_  8 ú x Ä »| ¾ ӓ É r 60 sccm Ü ¼– Ð Ä »t  % i Ü ¼ 9, R(%) = [CF

4

/(CF

4

+ CH

4

)] ×100 Ä »| ¾ Óq   H 75 % – Ð “ ¦& ñ % i  .

s

p  ˜ Г ¦  ) a ƒ  ½ ¨  õ \ " f Ä »| ¾ Óq  75 %\ " f a-C:F ~ Ã Ì }

Œ

•_  Ä »„   © œÃ º° ú כs   © œ ± ú “ É r ° ú כ`  ¦ ° ú   H  כ Ü ¼– Ð
 z Œ ¤



 [8,10]. 7 £ x ‚ Ã Ì ×  æ ì ø Í6 £ x – Ð_  ”  / B N • ¸  H 400 mTorr – Ð Ä »t 

% i “ ¦, 7 £ x ‚ à Ìr ç ß –“ É r 5ì  r 1 l x î ß – % i Ü ¼ 9, p-Si(100)_  “ : r

•

¸  H z  ´“ : r Ü ¼– Ð % i  . + þ A$ í  ) a y Œ •y Œ •_  a-C: F ~ à Ì} Œ •\  @ / ô

 Ç FTIRü < XPS ì  r$ 3 Ü ¼– Ð C-F, C-F

2

, C-F

₃

, C=C Õ ªo “ ¦ C=CF

2

1 p x _  bonding mode\  ¦ S X ‰ “   % i  . Ó s qw n ™ èB j' 

\

 ¦ s 6   x # Œ 3 “  u  J ?s ( \  + þ A$ í  ) a ~ à Ì} Œ •\ " f 9> h_  0 A u

\  ¦ ‚  × þ ˜ # Œ Õ ª ~ à Ì} Œ •_  ¿ ºa ü < Ï ã J] X Ö  ¦`  ¦ y Œ •y Œ • 8 £ ¤& ñ 

%

i  . + þ A$ í  ) a a-C:F ~ à Ì} Œ •_  Ä »„   © œÃ º  H C-V / B G‚  `  ¦ s 6   x

# Œ › ¸  % i  . + þ A$ í  ) a ~ à Ì} Œ •_  „  l & h  : £ ¤$ í “ É r MIS ½ ¨

›

¸\  ¦ s 6   x # Œ › ¸  % i Ü ¼ 9 s  ½ ¨› ¸\ " f_  „  F G“ É r · ú ˜À Ò

Fig. 1. FTIR spectra of a-C:F films deposited with a mixture of [CF

4

/(CF

4

+CH

4

)]×100 flow rate ratio of 75

% at differents rf powers from 400 to 800 W.

p

³ o u(Al) Ü ¼– Ð ”  / B N7 £ x ‚ Ã Ì % i Ü ¼ 9 Al „  F G _  t 2 £ §“ É r 250 µm, 500 µm, 750 µm“   dot  Û ¼ß ¼\  ¦ s 6   x # Œ 200 nm

&

ñ • ¸_  ¿ ºa – Ð 7 £ x ‚ Ã Ì % i  . rf power    o\  _ K  7 £ x ‚ à Ìô  Ç

~ Ã

Ì} Œ •_  Ä »„   © œÃ º  H C-V : £ ¤$ í / B G‚  Ü ¼– РÒ'  þ j@ / & ñ „  6   x

|

¾ Ó`  ¦ 8 £ ¤& ñ # Œ › ¸  % i  . # Œl " f “  „  · ú š“ É r -80 V \ 

"

f +80 V t     or (   .

III. + s ÇÊ Ý õ m Í À X Ø8 ý

Fig. 1“ É r [CF

4

/(CF

4

+CH

4

)] Ä »| ¾ Óq \  ¦ 75 % – Ð “ ¦ rf 

0 >\  ¦ 400 W \ " f 800 W t     or v €  " f z  ´“ : r \ " f 5ì  r 1 l x î ß – 7 £ x ‚ Ã Ì # Œ + þ A$ í  ) a a-C:F ~ à Ì} Œ •_  FTIR Û ¼& 7 ˜à Ô! 3  s

 . 1200 cm

⁻¹

% ò % i    H % ƒ\ " f
 è ß – x s ß ¼  H – Ð F 

g † < Æ (transverse optical:TO) — ¸× ¼– Ð" f F " é ¶ ™ è_    ½ + Ë\ 



  C-F

^x

”  1 l x — ¸× ¼\  › ' aº   ) a # Œ Q > h_    ½ + ˗ ¸× ¼ ×  æ

^ o

? ) a Û ¼& 7 ˜à Ô! 3 Ü ¼– Ð" f broad > 
 z Œ ¤ . 950 cm

⁻¹

\ 

"

f 1400 cm

⁻¹

% ò % i  t  rf power\  › ' a > \ O s  C-F

x

  

½

+ Ë\  › ' aº   ) a -C-F

3

(997 cm

⁻¹

), -C-F(1110 cm

⁻¹

), -C- F

₂

symmetric (1180 cm

⁻¹

) ü < asymmetric(1220 cm

⁻¹

), C-F

₃

(1280 cm

⁻¹

) Õ ªo “ ¦ C-F stretching (1350 cm

⁻¹

)

”

 1 l x — ¸× ¼\  ¦ ^  ¦ à º e ”   [11]. s  כ “ É r + þ A$ í  ) a a-C:F

~ Ã

Ì} Œ •? /\  # Œ Q 7 á x À Ó_  bond[ þ t s    ½ + ˝ ) a 4 Ÿ ¤ ½ + ˽ ¨› ¸\  ¦ s

À ғ ¦ e ” 6 £ §`  ¦ _ p ô  Ç . rf power 600 W t   H

[CF

4

/(CF

4

+CH

4

)] \  _  # Œ K o   ) a F s “ : r s  7 £ x  

#

Π-CF

2

, CF

2

-CF- Õ ªo “ ¦ CF

2

-CF

2

bond[ þ t – Ð" f ½ ¨$ í

 )

a F " é ¶ ™ è-õ   C-F

x

  ½ + ˽ ¨› ¸– Ð + þ A$ í H † d`  ¦ · ú ˜ à º e ”  Ü

¼ 9, rf power 600 W s  © œ\ " f  H   ½ + ˽ ¨› ¸_     o

 ß ¼t  · ú §6 £ §`  ¦ · ú ˜ à ºe ”  . s ü < ° ú  “ É r   õ [ þ t – Ð Â Ò'  rf power  7 £ x † < Ê\     -C-F

²

- bond[ þ t s  -C-F

²

-CF

3

bond – Ð   ½ + ËH † d`  ¦ · ú ˜ à º e ”  . { 9 ì ø Í& h Ü ¼– Ð PECVD  © œ u

\ " f rf power 7 £ x  €   [CF

₄

/(CF

₄

+CH

₄

)] precur- sor  e  ¦  Ý ¼   © œI \ " f F " é ¶ ™ è_  s “ : r ¢ ¸  H  Ö ¸$ í 7 á x s  7

£

x  l  M :ë  H \  F " é ¶ ™ è_  0 l x • ¸ 7 £ x – Ð d ” y Œ •ì ø Í6 £ x ‰ & ³ © œ[ þ t s

 { 9 # Qè ß –  [12]. 1470 cm

⁻¹

ü < 1512 cm

⁻¹

% ò % i \ " f
 

è ß – x s ß ¼[ þ t“ É r C " é ¶ ™ è[ þ t s  s ×  æ  ½ + Ë\  _ ô  Ç C=Cü <

C=C(aromatic) bond s  9, 1600 cm

⁻¹

\ " f 1800 cm

⁻¹

% ò

%

i \ " f broad > 
 è ß – x s ß ¼[ þ t“ É r FC=C, F

2

C=C ü <

F

2

C=CF- bond[ þ t s  . C=C stretching mode  H Ä »l  o

½

+ ËÓ ü t \ " f C " é ¶ ™ è H " é ¶ ™ è\  backbond– Ð | ¨ c M : €  • 1600 cm

⁻¹

% ò % i \ " f
 
 9, x s ß ¼_  0 Au   H H " é ¶ ™ è F

"

é

¶ ™ è\  _  # Œ ¨ 8 Š " é ¶| ¨ c M : Z  }“ É r ”  1 l x à º % ò % i Ü ¼– Ð ¼ # s 

{ 9

# Qè ß –  [10,13]. FC=C, F

²

C=C ü < F

²

C=CF- bond _  x

s ß ¼[ þ t“ É r rf power  500 W s  © œ\ " f Ì º§ 4 s 
 z Œ ¤



. s  כ “ É r a-C:F ~ à Ì} Œ •\ " f C=C bond| ¾ Ó 7 £ x – Ð ~ à Ì} Œ • ? / Â

Ò\ " f C-F

x

bond _  cross-link½ ¨› ¸ y Œ ™™ è   H  כ s  .

a-C:F ~ à Ì} Œ •\ " f C-F bond\  › ' aº   ) a   ½ + ˽ ¨› ¸\  ¦ ì  r$ 3 

l  0 A # Œ XPS C 1s x 9  F 1s C • ¸„    Û ¼& 7 ˜à Ô! 3 `  ¦ › ¸



 % i  . Fig. 2“ É r + þ A$ í  ) a a-C:F ~ à Ì} Œ •_  C 1sõ  F 1s C 

•

¸„   \  @ /ô  Ç Û ¼& 7 ˜à Ô! 3 `  ¦
  · p  כ s  . Fig. 2(a)  H C 1s Û ¼& 7 ˜à Ô! 3 Ü ¼– Ð" f C-CH

2

, C-CHF, C-CF

₂

Õ ªo “ ¦ CF- CF

₂

bond _  x s ß ¼– Ð ×  æ^ o ?÷ &# Q broad > 
 z Œ ¤Ü ¼ 9, Å

Ò x s ß ¼  H C-F bond s  . Fig. 2(b)  H F 1s Û ¼& 7 ˜à Ô! 3  Ü

¼– Ð" f x s ß ¼  H @ /^ ‰& h Ü ¼– Ð broad  9, 688.2 eV_    

½

+ Ë\  -t \  ¦ ° ú   H F-C bond – Ð + þ A$ í  ) a   [14].

Fig. 3  H Fig. 2 Ü ¼– РÒ'  rf power\    É r (F/C) " é ¶ ™ è _

 0 l x • ¸q \  ¦
  · p  כ s  . rf power 500 W  t   H (F/C) _  0 l x • ¸q  1.6Ü ¼– Ð / å L  y  7 £ x  % i “ ¦, 600 W\ 

"

f  H 1.7 – Ð  © œ Z  }“ É r ° ú כ`  ¦ ˜ Ð% i  . s  כ “ É r Fig. 1 _     õ

ü < q “ § # Œ ˜ Ѐ   a-C:F ~ à Ì} Œ •“ É r F " é ¶ ™ è-õ   C-F

2

  

½

+ ˽ ¨› ¸– Ð + þ A$ í H † d`  ¦ · ú ˜ à º e ”  . Õ ª Q
 600 W s  © œ\ 

"

f  H (F/C) _  0 l x • ¸q  y Œ ™™ è # Œ a-C:F ~ à Ì} Œ •_    ½ + ˽ ¨

›

¸  H -C-F

x

(x < 2) bond – Ð + þ A$ í H † d`  ¦ · ú ˜ à º e ”  . Fig.

1 _  FTIR   õ ü < q “ § # Œ ˜ Ѐ   rf power 600 W ˜ Ð



 Z  }“ É r rf power \ " f + þ A$ í  ) a a-C:F ~ à Ì} Œ •? /\ " f  H F " é ¶

™

è_   © œ@ /& h  " é ¶ ™ èq  y Œ ™™ è\  _  # Œ -C-CF, CF-C-CF

3

, -CF-C-CF Õ ªo “ ¦ CF-C-CF

²

1 p x _  bond– Ð crosslinking

 

½ + ˽ ¨› ¸\  ¦ ° ú   H  כ Ü ¼– Ð Ò q ty Œ •  ) a  . { 9 ì ø Í& h Ü ¼– Ð PECVD



© œu \ " f CF

4

ü < CH

4

precursor \  _  # Œ a-C:F ~ à Ì} Œ •+ þ A

Fig. 2. The XPS narrow scan spectra of (a) C 1s and (b) F 1s electron orbital of a-C:F films deposited with a mixture of [CF

₄

/(CF

₄

+CH

₄

)]×100 flow rate ratio of 75

% at rf powers of 500 W.

Fig. 3. The ratio of fluorine to carbon, in the a-C:F films as functions of rf powers.

$ í

\ " f  H rf power  Z  } Ü ¼€   precusor C

^∗

, F

^∗

, H

^∗

, (C- F)

^∗

, x 9 (C-F

₂

)

^∗

1 p x Ü ¼– Ð Ø  æì  r y  K o ÷ &# Q e  ¦  Ý ¼  x 9 • ¸

 7 £ x ÷ &€  " f Fõ  H s “ : r \  _  # Œ d ” y Œ •ì ø Í6 £ x Ü ¼– Ð C-F

²

bond  y Œ ™™ è # Œ (F/C) " é ¶ ™ è_  0 l x • ¸q  y Œ ™™ èô  Ç  [12].

Fig. 4  H + þ A$ í  ) a a-C:F ~ à Ì} Œ •_  Ä »„   © œÃ ºü < Ï ã J] X Ò  ¦`  ¦


Fig. 4. The refractive index and dielectric constant of the a-C:F films as functions of rf powers.



 · p  כ s  . Ä »„   © œÃ º  H rf power  400 W\ " f 600 W



t   H 2.8 \ " f 1.6Ü ¼– Ð y Œ ™™ è % i “ ¦, 800 W\ " f  H 1.9 – Ð 7

£

x  % i  . rf pwoer\    É r Ï ã J] X Ò  ¦“ É r Ä »„   © œÃ ºü < 1 l x { 9

ô  Ç    o\  ¦ ˜ Ð% i  . rf power 600 W\ " f 1.4– Ð  © œ

± ú

“ É r Ï ã J] X Ö  ¦`  ¦ ˜ Ð% i “ ¦, 800 W\ " f  H 1.5 – Ð 7 £ x  % i  .

s

   õ   H Fig. 3 _  (F/C) 0 l x • ¸_ q    õ ü < { 9 u ô  Ç . rf power  600 W\ " f  H a-C:F ~ à Ì} Œ •“ É r F " é ¶ ™ è-õ   C-F

^x

– Ð + þ

A$ í  ) a  כ Ü ¼– Ð Ò q ty Œ •  ) a  . Õ ª Q
 rf power 600 W s  © œ

\

" f  H d ” y Œ •´ òõ \    É r F" é ¶ ™ è_  y Œ ™™ è– Ð (F/C) " é ¶ ™ è_  0

l

x • ¸q   Œ •“ É r C-F

x

½ ¨› ¸– Ð    o   H  כ Ü ¼– Ð ˜ Г   . s 



© œ_    õ – Ð Â Ò'  a-C:F ~ à Ì} Œ •_  Ä »„   © œÃ º  H ~ à Ì} Œ •? /\ " f C-F

2

bond _  7 £ x \  _  # Œ y Œ ™™ è  9, s  כ “ É r F " é ¶ ™ è_  0

l

x • ¸\  _ ” > r ô  Ç .   " f ‘ : r ƒ  ½ ¨\ " f  H rf power  600 W \ " f  © œ Ä ºÃ ºô  Ç a-C:F ~ à Ì} Œ •`  ¦ + þ A$ í H † d`  ¦ ˜ Ð# Œ ‚  × þ ˜

&

h “   s “ : r õ  ×  æ$ í 7 á x`  ¦ % 3 `  ¦ à º e ”   H rf power  PECVD

~

½ ÓZ O \ " f ×  æ כ ¹ô  Ç 7 £ x ‚ à ̛ ¸| e ” `  ¦ · ú ˜ à º e ” % 3  .

IV. + s Ç Â ] Ø

a-C:F ~ à Ì} Œ •“ É r CF

4

ü < CH

⁴

™ D ¥ ½ + ËÛ ¼\  ¦  6   x # Œ TCPCVD ~ ½ ÓZ O \  _  # Œ + þ A$ í r (   . rf power 600 W \ " f + þ A$ í  ) a a-C:F ~ à Ì} Œ •“ É r C-F

2

, C-F

₃

, CF

₃

-CF

₂

, C=CF

2

x 9  CF=CF

₂

bond 1 p x Ü ¼– Ð   ½ + ˝ ) a C-F

x

½ ¨› ¸\  ¦

 ? /% 3 “ ¦, rf power 600 W s  © œ\ " f  H (F/C)" é ¶ ™ èq 

 y Œ ™™ èô  Ç C-F

x

  ½ + ˽ ¨› ¸\  ¦
 ? /% 3  . s  כ “ É r CF

4

ü <

CH

₄

™ D ¥ ½ + ËÛ ¼\  _ ô  Ç “ ¦x 9 • ¸ e  ¦  Ý ¼   © œI \ " f F s 

“

: r[ þ t s  { 9 Â Ò d ” y Œ •ì ø Í6 £ x \  ‚ à Ð# Œ l  M :ë  H s  . rf power

600W { 9  M : a-C:F ~ à Ì} Œ •_  Ä »„   © œÃ ºü < Ï ã J] X Ò  ¦“ É r 1.6 õ  1.4 – Ð  © œ ± ú “ É r ° ú כ`  ¦ ˜ Ð% i  . a-C:F ~ à Ì} Œ •_  Ä »„   © œÃ º



 H (F/C) " é ¶ ™ è0 l x • ¸_  q \  _ ” > r † < Êõ  TCPCVD ~ ½ ÓZ O \ 

"

f CF

4

Û ¼  H e  ¦  Ý ¼  x 9 • ¸ Z  }“ É r  © œI \ " f  H { 9  Ò

F s “ : r[ þ t s  d ” y Œ •ì ø Í6 £ x \  ‚ à Ð# Œ† < Ê`  ¦ ˜ Ð% i  .   " f ‘ : r ƒ  

½

¨\ " f  H CF

4

ü < CH

4

™ D ¥ ½ + ËÛ ¼\  ¦ PECVD ~ ½ ÓZ O Ü ¼– Ð a- C:F ~ à Ì} Œ •`  ¦ 7 £ x ‚ à ̽ + É  â Ä º, rf power 600 W\ " f  © œ Ä º Ã

ºô  Ç $ Ä »„   ~ à Ì} Œ •s  + þ A$ í H † d`  ¦ ½ ©" î % i Ü ¼ 9, C ‚  ç ß –   s

 100nm s  _  œ í“ ¦| 9 & h ™ è _  8 £ x ç ß –] X ƒ  } Œ •Ü ¼– Ð  6   x

0 p x † < Ê`  ¦ · ú ˜ à º e ” % 3  .

P

c p 8 ý ò k >

s

  7 Hë  H“ É r 1999¸  • ¸ ] jÅ Ò@ /† < Ɠ § µ 1 τ  l F K † < ÆÕ ü tƒ  ½ ¨q 

\

 _ K  ƒ  ½ ¨÷ &% 3  .

Y

c p w Š à U Ø ”  ô

[1] N. Ariel, M. Eizenberg, Y. Wang and S. P. Murarka, Mater. Sci. Semi. Proc. 4, 383 (2001).

[2] C. E. Bottani, A. Lamperti, L. Nobili and P. M.

Ossi, Thin Solid Films 433, 149 (2003).

[3] K. Endo, T. Tatsumi, Y. Matsubara and T. Hori- uchi, Jpn. J. Appl. Phys. 37, 1809 (1998).

[4] T. Homma, M. Ymaguchi, Y. Kutsuzawa and N.

Otsuka, Thin Solid Films 340, 237 (1999).

[5] T. Usami, K. Shimokawa and M. Yoshimaru, Jpn.

J. Appl. Phys. 33, 408 (1994).

[6] Y. Xin, Z. Y. Ning, C. Ye, X. H. Lu, S. L. Xiang, W. Du, S, Huang, J. Chen and S. H. Cheng, Surface Coatings Technology 173, 172 (2003).

[7] S. M. Yun, H. Y. Chang, K. S .Oh and C. K. Choi, Jpn. J. Appl. Phys. 38, 4531 (1999).

[8] Kyoung Suk Oh, Shou-Yong Jing, Chi Kyu Choi, Kwang Man Lee and Heon-Ju Lee, J. Korean Phys.

Soc. 39, 291 (2001).

[9] Kyoung Suk Oh, M. S. Kang, K. M. Lee, D. S. Kim and C. K. Choi, Thin Solid Films 345, 45 (1999).

[10] Gwon Sarm Kang, Chi Kyu Choi, Kwang-Man Lee, Heon-Ju Lee and Young Hun Yu, J. Korean Phys.

Soc. 42, S838 (2003).

[11] Jeong W. Yi, Young H. Lee and Bakhtier Farouk, TSF 374, 103 (2000).

[12] Sang Soo Han, Hun Rae Kim and Byeong-Soo Bae, J. Electrochem. Soc. 146, 3383 (1999).

[13] X. Wang, H. Harris, H. Temkin and S. Gangopad- hyay, App. Phys. Lett. 75, 3079 (2001).

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Chan and Lin Li, Surf. Interface Anal. 35, 852

(2003).

A Study on the Formation of a-C : F Films with a Low Dielectric Constant by Using CF ₄ /CH ₄ -TCPCVD

Duk Soo Kim

Department of Chemistry, Cheju National University, Jeju 690-756

Ho Jeong Ko and Chi Kyu Choi

^∗

Department of Physics, Cheju National University, Jeju 690-756 (Received 5 January 2005)

Fluorinated amorphous carbon films were deposited on p-type Si(100) substrates by using a transformer coupled plasma chemical vapor deposition (TCPCVD) system with a mixture of carbon tetrafluoride (CF

4

) and methane (CH

4

) gases. Fourier transformation infrared spectroscopy and X-ray photoelectron spectroscopy spectra showed that the bonding structure of the a-C:F film had C-F, C-F

2

, C-F

3

, C=CF

2

and CF=CF

2

bonds. The maximum value of the (F/C) atomic ratio was about 1.8 at an rf power of 600 W, and the a-C:F film had fluorine-rich functional groups of CF

x

bonds in addition to C-F

2

, C-F

3

, CF

3

-CF

2

, C=CF

2

and CF=CF

2

bonds, However, samples deposited at rf powers above 600 W had CF

x

bonds with reduced (F/C) atomic ratios. The lowest values of the relative dielectric constant (κ) and the reflective index (n) were 1.6 and 1.4, and were obtained for films deposited at an rf power of 600 W. Therefore, the dielectric constant of a-C:F films depens on the (F/C) atomic concentration ratio, and the bonding structure of the a-C:F

2

film changes with they rf power.

PACS numbers: 77.22.-d, 77.55.+f, 77.84.-s

Keywords: Dielectric constant, Interlayer Dielectric, Fluorinated amorphous carbon, Low dielectric constant film, Bonding structure

∗

E-mail: [email protected]