13–6
Real-time Monitoring of a Pulsed Power for Reactive Magnetron Sputtering Using
a LabVIEW System
F.L. Wen
1
, C.H. Wen
2
, I. Hsu
3
, H.S. Wu
4
and H.J. Wen
5
1
St. John’s University, Taipei, Taiwan, 25135, ericwen@mail.sju.edu.tw
2
National Chiao Tung University, Hsinchu, Taiwan, 30010, hsien@onlinenet.com.tw
3
Ta Hwa Institute of Technology, Hsinchu, Taiwan, 30740, hsuichien@yahoo.com.tw
4
Yuan Ze University, Taoyuan, Taiwan, 32003, cehswu@saturn.yzu.edu.tw
5
St. John’s University, Taipei, Taiwan, 25135, wenhj@mail.sju.edu.tw
Abstract. Due to a pulsed power offering the instant energy for
extremely high plasma density, the purpose of this study is to
develop the real-time monitoring system for the modern pulsed
plasma coating by the LabVIEW technique. One selected
exampl of the thin-film formation was testified based upon
various N
2
gas flows for depositing ZrN
x
film on the substrate of
a p-type (100) silicon wafer through pulsed-DC reactive
magnetron sputtering. The results indicate that the specific
pulsed parameters affect the crystallized status on the ZrN
x
film,
in which a pulsed power was monitored by a LabVIEW system.
Also, the characteristics of ZrN films in crystal orientations and
grain sizes have directly relationship to various N
2
flow rates.
Keywords: Reactive sputtering, pulsed magnetron coating,
zirconium-nitride film, layer characterization
1. Introduction
It is important to fabricate functional thin film with the
specific surface structure and properties. Due to the wide
applications of thin film engineering, they have the
various stabilities in thermal and chemical situation and
also demonstrate high hardness, anti-corrosion, and
magnetic and optical features. The interesting feature
involving the wide variation of electrical or semiconductor
resistivity depends upon the chemical composition ratio of
contents in compound films. There are two types of
preparations for thin films, such as CVD and PVD, and
also the PVD method is recovered as more popular
processing in recent decades [1-8]. An innovative concept
for thin film manufacturing by applying a GPIB card
combined with the commercial available LabVIEW
software tool has been proposed, based on a Windows
computer to construct a monitoring platform. LabVIEW, a
powerful graphical programming language developed by
National Instruments, is easy to learn and can be used to
develop a monitoring instrument rapidly. Once, this
instrument needs a modification without requiring any
new equipment. Users can create a whole set of
laboratory-instrument control functions using LabVIEW
but be less cost. Through a GPIB, an instrument-control
card, LabVIEW enables a computer to easily retrieve the
external signals, such as a real-time voltage and current
signals, to proceed with analysis, monitoring and control.
The current study is toward application in an on-line real-
time monitoring system for sputtering systems by GPIB
cards integrating with the LabVIEW software.
In order to investigate the influence of nitrogen flow
rate on characteristics of zirconium-nitride film (ZrN
x
)
through pulsed magnetron coating on the substrate of a p-
type (100) silicon wafer, the real-time monitoring concept
is introduced to the processing technique by various N
2
flow rates through a pulsed-DC reactive magnetron
sputtering with the unipolar-pulsing configuration.
Through analysis of experimental results, one of selected
processes as a sample for the pulsed power
implementation is demonstrated by X-ray diffraction
analysis.
2. Configuration of a Pulsed Plasma System
A schematic diagram of pulsed plasma system for
preparation of thin films in this work is shown in Figure 1.
The size of the stainless-steel reactor is 450×280×250
mm. The base pressure is evacuated to less 5 x 10
-4
torr by
a turbo-molecular pumping system. In the reactor, two
disc electrodes of 2” in the diameter are placed parallel to
each other, apart by 5 cm. Argon gas is used as a working
gas and nitrogenous gas is a reactive gas for nitride films.
Pulsed plasma is controlled around the substrate by the
magnetron mechanism from a pulsed power with power of
300 W, the pulsed duration of 5-50 ˩ s, the frequency
range of DC-50 kHz and the pulse repletion rate of 1-50
kHz. For the repetition rate of more than about 0.1 kHz,
the after-glow plasma by pulsed power remains near the
substrate during the off-time of the voltage pulse
arrangement.
Plasma Generation using a Pulsed Power [7]
The plasma discharge models as a quasi-steady state in
three-dimensional space in the reactor, and is assumed at a
constant forward speed. A schematic sketch of the pulsed-
plasma system is considered in this study as shown in
Figure 1. The device consists of two coaxial electrodes
(E1 and E2) separated by a hat-shaped insulator at one
end, while the other end is open. The space between the
electrodes is filled with the fed Argon gas. Both banks of
big capacitors (C1 and C2) are charged by DC power
supplies (DC1 and DC2) when the switch S1 and switch
S2 are opened. Via the high power transistors: T1, T1*,
and T2, T2* switching when the switch S1 and S2 are