2004-08-05

n=1--i1

10-5, 10-6

=(-2-2i)1/2c(2)1/2c

2

( ) ( )1 eeeen

kz-kz-1i-inkz-ikz- =

Snell 1

n

( )

2-12

-1

-1i--1ncos

2 cosn cos

c

2c

c

c

'

=

===

=

( n=1--i )

,

n=1--i (1)

10-510-6, 10-7n1,

( ) ( )

( ) ( )

=

+

=

r N x z f x M

r N x f x M

eA i i ii

i ii

eA ii

i ii

22

23

2

2

'

''

/

/

,(f, f)Zi/Mi1/2constant

*

**XAFS

(n) ()

(d)

()

X

0.0 0.2 0.4 0.6 0.8 1.0100

101

102

103

Incident Angle(deg)

Penetration Depth(nm)

10-4

10-3

10-2

10-1

100

Material: Si

X-ray:Cu-Ka1(1.54A) Reflectivity

( )

( )

R aR FR F

a i d R a EE

a

i

F F F

n n nn n n n

n n n n

n n n n n nn

R

n

n n n

n n n n n n n

+

+

+

=+

+

=

1 14 1 1

1 1

12

0

212

1 1 1

11

1

2 2

1 2

,, ,

, ,

,

, , ,

:

exp , ,

' exp /

( ) ( )( )

( )

+

12

2

2 1

2 2

16

2 2

, :

' , "

, ,

n n n

n A e n n n A e nN r f f MN r f

M

d

R :

R

0,12

0,12

En EnR

1

2

n()

d1

d2

dn=

R0,1

R1,2

R2,3

Rn-1,n

Rn+1,n=0

0 2 4 6 810-910-810-710-610-510-410-310-210-1100

Ref

lect

ivity

2Theta(deg)

SiO2/Si0.1nm

,

2(deg)

0.0 0.5 1.0 1.5 2.0 2.5 3.0

10-6

10-5

10-4

10-3

10-2

10-1

100

SiAl, , Cu

Ref

lect

ivity

CuAl

2.69, 3.99, 8.93g/cc

0.0 0.5 1.0 1.5 2.0 2.5 3.010

-7

10-610-510-410-310-210-1100

Al: 50nm

Al: 10nm

Ref

lect

ivity

2(deg)

SiAl

0.0 0.5 1.0 1.5 2.0 2.5 3.010-1010-910-810-710-610-510-410-310-210-1100

Ref

lect

ivity

2(deg)

Si

Al:50nm 1

21=2=0nm

1=1nm, 2=0nm

1=0nm, 2=1nm

TEM

Top-OxNitrideBottom-Ox

120(2.21g/cm3) 110 180(2.88g/cm3) 170 45(2.19g/cm3) 50

4.55.54.212

0.0 0.5 1.0 1.5 2.0 2.5 3.0

10-5

10-4

10-3

10-2

10-1

100 Sample:ADN-255

Ref

lect

ivity

2(deg)

* Si3N4(3.20g/cm3), SiO2( 2.30g/cm3)

SiOSiO: 110: 110

SiNSiN: 170: 170

SiOSiO: 50: 50

Spacer

curecure

frameworkframework

(Silica network)(Silica network)

spacerspacer

(organic polymer)(organic polymer)

organicorganic--inorganic hybrid gelinorganic hybrid gel porous filmporous film

SilicaSilica oligomeroligomer /Organic spacer/Solvents (mixture)/Organic spacer/Solvents (mixture)

SpinSpin--on (on (Si Si wafer)wafer)

GelationGelation & Solvent removal& Solvent removal

Organic Spacer RemovalOrganic Spacer Removal

(Cure (Cure

PorousPorous LowLow--kk FilmFilm

Cure

Spin coatGelation

( R.T. )

Porosity can be controlled by polymer/silica ratio

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.810-4

10-3

10-2

10-1

100

(deg)

The dielectric constant The dielectric constant vsvs film density for film density for

Porous silica thin filmsPorous silica thin films

Density (g/cm3)

Die

lect

ric

con s

t ant

Cure

Spin coatGelation

( R.T. )

Spin coat

nm

Porous 1.00g/cc, 295nm

Porous/Si-waferLow-k 1

Layer Density(g/cc) Thickness(nm) Roughness(nm) 0.5Porous 1.00 295 0.3(fix)Si 2.33 (fix) ---

0.2 0.3 0.4 0.5 0.6 0.7 0.810-3

10-2

10-1

100

2Theta(deg)

Calculation

10-3

10-2

10-1

100KP2

Measurement

Low-k 1

0.2 0.3 0.4 0.5 0.6 0.7 0.810-3

10-2

10-1

100

2Theta(deg)

Calculation

10-3

10-2

10-1

100KP2

Measurement

Porous

1.04g/cc, 554nm

/Si-wafer

Layer Density(g/cc) Thickness(nm) Roughness(nm) 0.3 1.04 554.0 0.3(fix)Si 2.33 (fix) ---

0.2 0.3 0.4 0.5 0.6 0.7 0.810-3

10-2

10-1

100

2Theta(deg)

Calculation

10-3

10-2

10-1

100

SiLK

Measurement

0.2 0.3 0.4 0.5 0.6 0.7 0.810-3

10-2

10-1

100

2Theta(deg)

Calculation

10-3

10-2

10-1

100

SiLK

Measurement

Layer Density(g/cc) Thickness(nm) Roughness(nm) 0.3 1.04 554 0.5 1.25 6 0.5Porous 1.00 295 0.3(fix)Si 2.33 (fix) ---

/Porous/Si

//Porous

1.251.2566nmnm

(3(38nm)8nm)

0.5 0.6 0.7 0.810-3

10-2

10-1

100

2Theta(deg)

Calculation

10-3

10-2

10-1

100

SiLK/KP2

Measurement

Low-k 1

0.5 0.6 0.7 0.810-3

10-2

10-1

100

2Theta(deg)

Calculation

10-3

10-2

10-1

100

SiLK/KP2

Measurement

*

Si(001)

Sample 19002.5

Sample 2Si

2=0.8, 1.0, 1.2, and 1.5Sample 1, 2

Sample 1

Sample 2

0m 5m 10m

10nm

(a)

0m 5m 10m

30nm

(b)

Sample 1

Sample 2

Thickness of SiO2: 45.6nm (by x-ray reflectivity)

Surface roughness: 0.4nm (by x-ray reflectivity)

Lateral correlation length: 200nm

Thickness of SiO2: 65.4nm

Surface roughness: 4.1nm

Lateral correlation length: 10nm

AFM images

10ppm/100ppm/

100nm10ppm/

0 50 100 150 200 250 300 350 400

0.87

0.88

0.89

0.90

B Data1_B

Density (g/cm3)

Temperature ( )

16ppm

DataLinear fit

Y = A + B X

Parameter Value error

-----------------------------------------------

A 0.88945 0.00192

B -4.94682E-5 7.30003E-6

-----------------------------------------------

SD N P

-----------------------------------------------

-0.94964 0.00243 7 0.00106

-----------------------------------------------

Coefficient of linear expansion is 1.6 * 10-5/K