| Summary: | 碩士 === 國立成功大學 === 材料科學(工程)研究所 === 83 === The RF magnetron sputtering technique was employed in this
study to obtain AlN thin films on silicon and glass substrat-
es. The reaction atmosphere was a mixture of argon and nitr-
ogen and the selected sputtering targets were either aluminum
or AlN . By changing the RF power, the chamber pressure ,and
the N2/Ar ratio , the aluminum nitride thin film that with C-
axis preferred orientation was observed. This is believed to
substantially benefit the futural application of this materi-
al in packaging industry. The crystallography of the costed
films was analyzed by x- ray diffraction (XRD) and by
operating the scanning electron microscope (SEM) for film
surface property and sample cross- section morphology , and by
practicing the alfa-step analysis for film thickness. Besides
, the composition and its depth of profile of AlN in the as-
sputtered film were also investi- gated using electron probe
microscope analysis (EPMA) and se- condary ion mass spectrum
(SIMS) techniques.The I-V and C-V curves of the as-sputtered
film are measured to clarify the electric properties. The
experimental results indicated that the optimum sputte- ring
conditions were chamber pressure at 3 mTorr, N2/Ar ratio at
0.15 (for AlN target) and 0.5 (for Al target), RF power at more
than 400W and the substrate temperature at room temperat- ure.
The AlN film was found to be with excellent surface fl- atness
(Ra=20nm) , Al/N atomic ratio closed to 1 , and in the C-axis
preferred orientation. The SEM observation showed the
morphology of columnar grains existed in the AlN film. The
deposition rate of the AlN film, when the RF power was set at
400W, was 28-32 nm/min using the Al target and 38-42 nm/min u-
sing the AlN target. The electric resistivity and the specif-
ic dielectric constant of the AlN thin film are 1E10-1E11 ohm-
cm and 10 from I-V and C-V curves , respectively .
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