Properties of SiCN films prepared by Cathode Coupled P-CVD
Using Liquid Source Material
Research and Development Department, Samco Inc.
18th International Symposium on Plasma Chemistry (ISPC-18) で発表
Introduction
【2007年8月26～31日 京都大学】
Application for optical film
Plasma Chemical Vapor Deposition (P-CVD) is a method for obtaining
the functional films such as SiN, SiO2. These films are indispensable in fields
such as semiconductor, optics and MEMS, etc.
Reflectivity of 4%
Reflectivity of 0%
SN1-SiN
(80℃)
HMDS-SiN
（80℃）
100
Heated piping (100 °C)
Tranmitivity [%]
Plasma Chemical Vapor Deposition (cathode-coupled P-CVD)
NH3
H2
LS-SiN（0.1μm）
SN1-SiN
HMDS-SiN
（300℃）
80
LS-SiN（0.03μm）
60
Substrate
40
SiH4-SiN
Reflectivity of 10%
20
Shower head electrode
0
400
SN1
HMDS
reservoir
Substrate
Exhaust
500
600
700
800
Wavelength [nm]
LS-SiN（0.03μm）
Stage electrode
Constant temperature
box (60 °C)
Coupling condenser
Substrate
RF Generator
(13.56 MHz)
Fig.7 Optical transparency of SiCN and SiH4-SiN.
・ SiCN film is possible on region substrates for instance, plastic.
Application for ELO-GaN
C/Si
N/Si
Deposition rate (nm/min)
C/Si, N/Si (XPS)
0.8
0.6
0.4
0.2
250
0
200
-100
150
-200
100
-300
50
-400
0
0
0.25
0.5
H2/(NH3+H2)
0.75
1.0
-500
200
300
400
500
600
RF power (W)
Fig.4 Variation of C/Si and N/Si in SiCN
films as a function of the flow ratio
H2/(NH3+H2)
Fig.5 Rerations between deposition
rate and film stress and RF power.
・ It is impossible to controlled the content of C/Si.
・ The films stress, negative values means compressive, increased from -240 MPa
to -405 MPa with RF power increase, and saturated at -405 MPa.
Application for MEMS
By chemical stability of SiCN films,
we consider that SiCN films can be
applied wet etching mask or selfsupporting films for MEMS devices.
Table 1 Wet etching rates for base/acid solutions.
Etchant
Concentration
(wt%)
Etchant temp.
(°C)
Etching rate
(nm/min)
BHF
HF 7.1
NH4F 34.3
25
0.018
KOH
30
85
0.058
TMAH
25
80
0.018
5V
Cu
Cr
SN1-SiN
Passivation film＝HMDS-SiN
Glass
500 nm
SiCN
Sapphire
φ = 0°
φ = 90°
FWHM
225 arcsec
Φ= 0°
273 arcsec
Φ= 90°
-4000 -2000
2000
0
SiH4-SiN
FWHM
203 arcsec
Φ= 0°
258 arcsec
Φ= 90°
-4000 -2000
GaN regrowth
4000
0
2000
4000
Δω (arcsec)
Application for Semiconductor
We deposited the SiCN films using
Cathode Coupled and Anode Coupled PCVDs. The SiCN films have unique
characteristics which SiH4 use SiN films
does not have. We consider that the SiCN
films are candidate material for the practical
applications in various industrial fields.
1.E+00
1.E-02
1.E-04
1.E-06
1.E-08
1.E-10
1.E-12
-10
-8
-6
-4
-2
0
2
Voltage　V)
Fig.9 I-V characteristic
passivated pin diode.
of
SiCN
Conclusion
Resistance value ［ohms］
85 ℃
85 %RH
Mask
Fig.8 X-ray rocking-curve of ELO
GaN using SiCN and SiH4-SiN masks.
Application for diffusion barrier of metal
These results were considered that
the diffusion of Cr metal or impurities
contained grass substrate was pro-tected
using SiCN film, and considered that it
is a wet-proofing in the SiCN film.
X-ray
direction
Logarithmic X-ray Intensity (a.u.)
1.0
Film stress (MPa)
Basic characteristics of SiCN films
The result of ELO using the SiCN
stripe film shows that the GaN(0001)
crystal grows up, and there is no
imperfect alignment from <0001>
direction because the both dif-fraction
peaks, φ=0° and φ=90°, are single.
On the other hand, even when SiH4 use
SiN film is used as a ELO mask,
crystallinty of GaN(0001) is almostly
the same level in case of SiCN ELO
mask. However, because the diffraction
peak, φ=90°, is not single, it means
imperfect alignment from <0001>
direction.
Current　A)
Fig.2 Concept of the plasma chemical vapor
deposition technique.
1011
HMDS-SiN
SN1-SiN （L&S=50 μm）
1010
109
108
Glass （L&S=40 μm）
107
Acknowledgements
106
The authors would like to thank Dr. H. Miyake in Mie University, for useful
discussion concerning GaN-ELO application.
105
Glass （L&S=50 μm）
104
0
500
1000
1500
2000
We deposited the SiCN films using Cathode Coupled and Anode Coupled
P-CVDs. The SiCN films have unique characteristics which SiH4 use SiN films
does not have. We consider that the SiCN films are candidate material for the
practical applications in various industrial fields.
2500
Testing time ［hours］
Fig.6 Life-time test of resistance for SiCN coated and bare glass.
3000
References
[1]
A. Ogishi, S. Motoyama, M. Sawai, T. Tatsuta and O. Tsuji, Jpn. J. Appl. Phys. 42 (2003) L1090