Sputtering apparatus

A sputtering apparatus has a pressure resistant vessel, from which gas in discharged and into which gas for sputtering is supplied, a substrate disposed in the vessel to be formed with a film at one surface thereof, a target disposed oppositely to one surface of the substrate to be formed of a substance to become a material of the film, a magnet provided on the surface of the target oppositely to the substrate to generate a magnetic field for confining a plasma in the vicinity of the surface of the target opposed to the substrate, a plate-shaped anode disposed between the substrate and the target to be formed with an opening of the shape in which at least one side is larger than the profile of the substrate at a position opposed to the substrate, and a sputtering current supplier between the anode and the target. The anode is made of a conductor. An opening larger than the profile of the substrate is formed at a position of the anode opposed to the substrate.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a magnetron type sputtering apparatus for 
forming a thin film on a substrate. 
2. Description of the Related Art 
A magnetron type sputtering apparatus has been widely used as a method of 
forming a thin film such as a transparent conductive film a metal film or 
an insulating film on a substrate such as a glass substrate. A 
conventional magnetron type sputtering apparatus is constructed as shown 
in FIG. 1 and FIG. 2. More specifically, in a pressure resistant vessel 1, 
a substrate S to be covered with a desired film, a target T opposed to the 
substrate S under the substrate S, a magnet M disposed under the target T, 
and an anode A between the target T and the substrate S are disposed. The 
magnet M is provided to seal a plasma by a magnetic field, and provided 
with an S pole around an N pole which is laterally long. The anode A is 
formed in a loop shape of a conductive wire material and disposed to 
surround the outer periphery of the substrate S. 
This sputtering apparatus generates a plasma by supplying a discharge 
current between a cathode electrode of the target T and the anode A and 
sputters with the plasma. The plasma is confined in the surface of the 
target by a magnetic field indicated by lines f of magnetic force of the 
magnet M. The target T is sputtered by the plasma confined in the magnetic 
field of the magnet M, and the sputter particles thus sputtered are flown 
toward the substrate S, and deposited on the surface of the substrate S. 
As a result, the target T is cut more on the surface in the portion having 
higher density of the plasma to form an erosion Ta. Since the erosion Ta 
becomes high in the density of the plasma on the surface of the target 
corresponding to an intermediate point between the S pole and the N pole 
of the magnet M, the erosion Ta is formed in a ring shape on the surface 
of the target T corresponding to the intermediate point between the S pole 
and the N pole of the magnet M, and deepened as the sputtering time is 
elapsed. When the sputtering time becomes long so that the depth of the 
erosion Ta becomes deep to arrive at the lower surface of the target, the 
target is replaced. 
There is also known an in-line type sputtering apparatus for continuously 
depositing films on a number of substrates to enhance the efficiency of 
depositing the films as a sputtering apparatus. The in-line type 
sputtering apparatus is constructed schematically as shown in FIG. 3. More 
particularly, in a sputtering chamber 10, an inlet chamber 12 is bonded to 
the front side of the sputtering chamber 10, and an outlet chamber 13 is 
bonded to the rear side of the sputtering chamber 10 through airtight 
doors (not shown). A substrate 1S to be formed with a film is mounted on a 
substrate carrier (not shown), and introduced into the inlet chamber 12. 
The inlet chamber 12 is reduced under pressure, the airtight door (not 
shown) is then opened, and the substrate 1S is carried into the sputtering 
chamber 10, and formed with a film by sputtering while the substrate 1S is 
moved in the sputtering chamber 10. Then, the airtight door (not shown) is 
opened, the substrate 1S is carried into a pressure-reduced outlet chamber 
13, the outlet chamber 13 is returned to the atmospheric pressure, and the 
substrate carrier is then delivered. 
A heater 14 for heating the substrate 1S carried into the sputtering 
chamber 10 is provided in the sputtering chamber 10, and a film forming 
portion 17 is provided at the rear of the heater 14 (at the front of the 
substrate 1S in the moving direction). The film forming portion 17 is 
composed of a target 1T opposed to the film forming surface of the 
substrate 1S moving in the sputtering chamber 10, a magnet (permanent 
magnet) 1M disposed behind the target 1T for generating a magnetic field 
for confining a plasma, and an anode 1A made of a conductive metal wire 
material disposed opposed to the target 1T. 
When a metal oxide film such as, for example, an ITO is formed by this 
sputtering apparatus, argon gas (Ar) and oxygen gas (O.sub.2) are 
introduced as sputtering gases into the sputtering chamber 10, a 
sputtering is conducted by the target 1T made of ITO in the sputtering gas 
atmosphere to form an IT0 on the film forming surface of the substrate 1S. 
The substrate 1S carried into the sputtering chamber 10 is heated to a 
predetermined temperature (a temperature capable of forming a film by 
sputtering) in the step of passing the heater 14 while moving the 
substrate 1S by a substrate carrier, and formed with a film by sputtering 
while passing a film forming portion. The sputtering is conducted by 
supplying a discharge current between a cathode electrode of the target 1T 
and an anode 1A. A plasma generated by supplying the discharge current is 
confined in the vicinity of the surface of the target 1T by a magnetic 
field of the magnet 1M. Sputtering particles sputtered from the target 1T 
by the plasma are flown toward the substrate 1S, and deposited on the 
substrate 1S. In the in-line type sputtering apparatus, the target 1T is 
also cut more, similarly to the above-mentioned sputtering apparatus of 
FIGS. 1 and 2, on the surface in the higher density of the plasma as the 
sputtering time is elapsed to form a ring-shaped erosion 1Ta on the 
surface of the target 1T corresponding to the intermediate point between 
the S-pole and the N-pole of the magnet 1M. The erosion 1Ta becomes deep 
as the sputtering time becomes long. When the depth of the erosion 1Ta 
reaches the lower surface of the target, the target is replaced. 
In order to replaced the target, as shown in FIG. 4, an opening 10a is 
formed at the sidewall of the sputtering chamber 10. The target 1T is 
attached to the inner surface of an openable door 11 made of a copper 
plate for sealing the opening, and the door 11 is opened when the target 
1T is consumed to its available limit to replace the target 1T. 
The magnet 1M is attached to the outer surface of the door 11, and the 
anode 1A is attached to an anode supporting member 15 provided in the 
sputtering chamber though an insulating member 16. 
The sputtering rates (film depositing efficiency on the substrate S, 1S) of 
the sputtering apparatuses described above are determined by the discharge 
current supplied between the target T, 1T and the anode A, 1A. The larger 
the discharge current is supplied, the higher the sputtering rate becomes. 
However, in the conventional sputtering apparatuses described above, there 
arises a problem that if the discharge current is increased, a discharging 
state becomes unstable. Therefore, it was difficult to raise the 
sputtering rate by increasing the discharge current value. 
In the conventional sputtering apparatuses described above, the linear 
anodes A, 1A are disposed to surround the substrates S, 1S. Since a 
difference in the discharging states occurs above and below the anodes A, 
1A and/or at the right and left sides of the peripheries of the anodes A, 
1A, the degrees of the progresses of the erosions Ta, 1Ta of the targets 
T, 1T become irregular as shown in FIG. 1 when the sputtering is repeated. 
If the erosions Ta, 1Ta of the targets T, 1T are proceeded to the depth 
arriving at the lower surfaces of the target T, 1T even only at the 
portions of the targets T, 1T, though the target material having a 
thickness sufficiently available for use remains under the erosions Ta, 
1Ta of the other portion, the targets T, 1T become impossible to be used 
at this time. Therefore, the above-described conventional sputtering 
apparatus has a problem in which the utility efficiency of the target A is 
deteriorated. 
In the conventional sputtering apparatuses described above, the target 1T 
is attached to the inner surface of the openable door 11, and the anode 1A 
is mounted in the sputtering chamber 10. Therefore, it has a problem that 
regulation of the position of the anode 1A to the target 1T is very 
difficult. In other words, in order to regulate the position of the anode 
1A to the target 1T, the steps of closing the openable door 11, opposing 
the target 1T on the inner surface of the openable door 11 to the anode 1A 
in the sputtering chamber 10, opening the openable door of the sidewall of 
opposite side to the sputtering chamber 10, checking the position of the 
anode 1A from the opening of the opposite side, then opening the openable 
door 11, correcting the position of the anode 1A, again closing the 
openable door 11, and checking the position of the anode 1A after 
correction from the opening of the opposite side must be repeated. 
Accordingly, the above-mentioned conventional sputtering apparatus has a 
problem that the position regulating work of the anode 1A is very 
complicated in a low efficiency. 
It is an object of the present invention to provide a sputtering apparatus 
which can solve the above-described problems and produce a stable and 
uniform discharge state with a large discharge current, thereby enhancing 
a sputtering rate and forming a film in high efficiency. 
SUMMARY OF THE INVENTION 
In order to achieve the above-described object, there is provided according 
to the present invention a sputtering apparatus comprising a pressure 
resistant vessel; means connected to the pressure resistant vessel for 
discharging gas in the pressure resistant vessel; means connected to the 
pressure resistant vessel for supplying gas for sputtering into the 
pressure resistant vessel; a substrate disposed in the pressure resistant 
vessel to be formed with a film at least on one surface thereof; a target 
disposed oppositely to one surface of the substrate in the pressure 
resistant vessel to be formed of a substance to become a material of the 
film to be coated on the surface of the substrate; a magnet provided on 
the surface of said target oppositely to the substrate for generating a 
magnetic field for confining a plasma in the vicinity of the surface of 
the target opposed to the substrate; a plate-shaped anode disposed between 
the substrate and the target to be formed with an opening of the shape in 
which at least one side is larger than the profile of the substrate at a 
position opposed to the substrate; and means for supplying a sputtering 
current between the anode and the target. 
According to the sputtering apparatus of the present invention, the anode 
is formed of the flat plate made of the conductive material having the 
opening larger at least one side than the profile of the substrate to be 
formed with the film. Therefore, even if a discharge current is large, a 
stable discharge state is obtained, thereby enhancing the sputtering rate. 
Since the anode has the opening equal to the plane which is perpendicular 
to the target and passes through the intermediate point between the N-pole 
and the S-pole of the magnet or at the outside therefrom and/or having 
inner edges at equal distance from the plane, the discharge states of the 
portions of the target become substantially equal and hence the degrees of 
progress of the erosions of the target as the sputtering time is elapsed 
is made uniform, thereby improving the utility efficiency of the target. 
Additional objects and advantages of the invention will be set forth in the 
description which follows, and in part will be obvious from the 
description, or may be learned by practice of the invention. The objects 
and advantages of the invention may be realized and obtained by means of 
the instrumentalities and combinations particularly pointed out in the 
appended claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
A first embodiment of the present invention will now be described in detail 
with reference to FIGS. 5 and 6. 
In FIGS. 5 and 6, a magnet (permanent magnet) 102 for generating a magnetic 
field to seal a plasma is disposed in the bottom of a pressure resistant 
vacuum vessel 101. A loop-shaped S-pole surrounding an N-pole having a 
laterally long length is formed around the N-pole in the magnet 102 in 
such a manner that the interval between the N-pole and the S-pole is equal 
in the entire region. A target 103 is disposed on the magnet 102. A 
substrate 104 is made of glass or the like, and a film is formed on the 
substrate 104. The substrate 104 is disposed oppositely to the target 103 
above the target 103 in the upper section in the vacuum vessel 101. A 
discharge current is supplied to an anode 105, which is formed in a flat 
plate having an opening 105a for passing sputtering particles. The anode 
105 is disposed horizontally between the substrate 104 and the target 103. 
The opening 105a of the anode 105 is larger than the profile of the 
substrate 104 and has an inner edge coincident with or at an equal 
distance from a plane x perpendicular to the target 103 through the 
intermediate point between the N-pole and the S-pole of the magnet 102 
(hereinafter referred to as "an intermediate point of the magnet"). In 
this embodiment, the area of the opening 105a is formed to be slightly 
larger than that of the region surrounded by the plane x, and the anode 
105 is disposed in a state that the distance between the opening edge of 
the opening 105a and the plane x is equal over the entire periphery of the 
opening 105a. In other words, a distance d.sub.1 between the opening edge 
of one side of the opening 105a of the anode 105 and the plane 1 and a 
distance d.sub.2 between the opening edge of the other side of the opening 
105a and the plane x satisfies d.sub.1 =d.sub.2. In this embodiment, the 
opening 105a of the anode 105 is formed in a rectangular shape of 
laterally long state, while the profile of the magnet 102 is formed in 
arcuate shapes at the corners, and the distances between the four corners 
of the opening 105a and the plane x may be formed to be slightly larger 
than the distances d.sub.1, d.sub.2 between the opening edges of the other 
portions and the plane x. 
The sputtering apparatus holds a predetermined low pressure state in the 
vacuum vessel by evacuating the vessel from a discharge valve 107 while 
supplying sputtering gas from a supply valve 106 and by supplying a 
discharge current from a power source 108 between the cathode electrode of 
the target 103 and the anode 105 with the target 103 as a cathode 
electrode, thereby sputtering. A plasma generated by supplying the 
discharge current is confined on the surface of the target 103 by the 
magnetic field of the magnet 102. In FIG. 5, the magnet 102 generates 
lines f of magnetic force. Sputtering particles sputtered by the plasma 
confined by the magnetic field of the magnet 102 are flown toward the 
substrate 104, and deposited on the substrate 104 through the opening 105a 
of the anode 105. 
In the sputtering apparatus as described above, the anode 105 is formed in 
a flat plate shape having the opening 105a for passing the sputtering 
particles. Therefore, even if the discharge current is increased, the 
discharge state is stably held. Accordingly, according to the sputtering 
apparatus, the sputtering rate can be raised by increasing the discharge 
current value. Since the opening 105a of the anode 105 is formed in the 
area larger than that of the region surrounded by the perpendicular plane 
x passing the intermediate point of the magnet and the distances d.sub.1, 
d.sub.2 between the opening edges and the plane x are equal over the 
entire periphery of the opening 105a as described above, the discharge 
states of the portions of the target 103 become substantially equal. 
Therefore, according to the sputtering apparatus described above, the 
degree of the progress of the erosion 103a of the target 103 becomes 
uniform as the sputtering time is elapsed, thereby improving the utility 
efficiency of the target 103. In the embodiment described above, since the 
distances between the four corners of the opening 150a of the anode 105 
and the perpendicular plane x are slightly larger than the distances 
d.sub.1, d.sub.2 between the opening edges of the other portions and the 
plane x, the degree of the progress of the erosion 103a of the target 
portion corresponding to the portion is slightly different from the other 
portion, but the progress of the erosion 103a of this target portion is 
delayed from that of the erosion 103a of the other portion due to the 
large distance between the opening edge of the anode 105 and the plane x 
passing the intermediate point of the magnet, there arises no problem. 
In the first embodiment described above, the S-pole of the loop shape 
surrounding the N-pole is formed around the one N-pole in the magnet 102. 
However, the present invention is not limited to the particular 
embodiment. For example, when the numbers of the N-poles and S-poles are 
increased and a plurality of openings 105a are formed correspondingly at 
the anode 105, the sputtering rate can be raised with the same discharge 
current value. 
FIGS. 7 and 8 show a second embodiment of the present invention. In this 
embodiment, a magnet 112 for confining a plasma is formed with two 
parallel rows of N-poles each having a laterally long length and with 
8-shaped S-poles of loop shape surrounding the respective N-poles around 
the respective N-poles in such a manner that the intervals between the 
N-poles and the S-poles are equal in all region. A flat plate-shaped anode 
115 disposed horizontally between a substrate 114 and a target 113 is 
formed with two openings 115a and 115b corresponding to regions surrounded 
by a plane x2 perpendicular to the target 113 through a region surrounded 
by a plane x.sub.1 perpendicular to the target 113 through the 
intermediate point (of the magnet) between the one N-pole and the S-pole 
around the N-pole of the magnet 112 and through a region surrounded by a 
plane x.sub.2 perpendicular to the target 113 through the intermediate 
point (of the magnet) between the other N-pole and the S-pole around the 
N-pole of the magnet 112. The two openings 115a and 115b respectively 
coincide with the planes x.sub.1 and x.sub.2, or have inner edges at the 
positions of equal distance from the planes x.sub.1 and x.sub.2 toward the 
outside. These two openings 115a and 115b form a substantially larger one 
opening than the profile of the substrate 114. In this embodiment, the 
sizes of the openings 115a and 115b are formed to be slightly larger than 
those of the regions surrounded by the planes x.sub.1 and x.sub.2. The 
anode 115 is disposed in a state that the distances between the opening 
edges of the openings 115a and 115b and the planes x.sub.1, x.sub.2 are 
equal over the entire peripheries of the openings 115a and 115b. In other 
words, distances d.sub.1, d.sub.3 between the opening edges of one sides 
of the openings 115a and 115b of the anode 115 and the planes x.sub.1, 
x.sub.2 as well as distances d2, d4 between the opening edges of the other 
sides and the planes x.sub.1, x.sub.2 satisfy d.sub.1 =d.sub.2 =d.sub.3 
=d.sub.4. As in this embodiment, the openings 115a, 115b of the anode 115 
are formed in rectangular shapes each having a laterally long length, the 
magnet 112 is formed in an arcuate shape at the corners so that distances 
between the four corners of the openings 115a and 115b and the planes 
x.sub.1, x.sub.2 may be formed to be slightly larger than the distances 
d.sub.1, d.sub.2, d.sub.3, d.sub.4 between the opening edges of the other 
portion and the planes x.sub.1, x.sub.2. In FIGS. 7 and 8, the members 
corresponding to those in FIGS. 5 and 6 are denoted by the same reference 
numerals, and the description thereof will be omitted. 
As in this embodiment, when the magnet 112 for confining the plasma is 
formed with two rows of N-poles and with S-poles around the respective 
N-poles and the anode 115 is formed with two openings 115a and 115b 
corresponding to two regions surrounded by the planes x.sub.1, x.sub.2 
perpendicular to the target through the two intermediate point of the 
magnets 112, the sputtering rate can be increased by about three times as 
large as that of the sputtering apparatus shown in FIGS. 5 and 6 by the 
same discharge current value. 
Even in this embodiment, since the openings 115a and 115b of the anode 115 
are formed in an area larger than that of the respective regions 
surrounded by the planes x.sub.1, x.sub.2 passing the two intermediate 
points of the magnet 112 and the distances between the opening edges of 
the openings 115a, 115b and the planes x.sub.1, x.sub.2 are equal over the 
entire peripheries of the openings 115a and 115b, the discharge state can 
be stably held even if the discharge current is increased, and hence the 
sputtering rate can be raised by increasing the discharge current value 
similarly to the embodiment described above. Further, the degree of 
progress of the erosion 113a of the target 113 can be made uniform even in 
the two erosions corresponding to the two poles as the sputtering time is 
elapsed, thereby improving the utility efficiency of the target 113. 
As in the first and second embodiments described above, the areas of the 
openings 105a, 115a, 115b of the anodes 105, 115 may be formed to be the 
same as those of the regions surrounded by the planes x.sub.1, x.sub.2. In 
summary, the openings 105a, 115a, 115b of the anodes 105, 115 may be 
formed in area larger than those of the regions surrounded by the planes 
x.sub.1, x.sub.2 and the distances between the opening edges and the 
planes x, x.sub.1, x.sub.2 may be formed to be substantially equal over 
the entire peripheries of the openings 105a, 115a, 115b. When the areas of 
the openings 105a, 115a, 115b are formed to be the same as those of the 
regions surrounded by the planes x, x.sub.1, x.sub.2, the distances 
d1,d.sub.2, d.sub.3, d.sub.4 between the opening edges and the planes x, 
x.sub.1, x.sub.2 satisfy d.sub.1 =d.sub.2 =d.sub.3 =d.sub.4 =. 
In the first and second embodiments described above, the openings 105a, 
115a, 115b of the anode 115 are formed in rectangular shapes each having a 
laterally long length. However, the invention is not limited to the 
particular embodiments. For example, the openings 105a, 115a, 115b may be 
formed to be similar to the regions surrounded by the planes x, x.sub.1, 
x.sub.2 through the intermediate point of the magnets. Thus, the distances 
between the opening edges of the openings 105a, 115a, 115b and the planes 
x, x.sub.1, x.sub.2 may be formed to be equal over the entire peripheries 
of the openings, and the degree of progress of the erosion 103a of the 
target 103 may be uniform in the entire region. 
A third embodiment of the present invention applied to an in-line type 
sputtering apparatus will be described with reference to FIGS. 9 to 16. 
FIG. 9 shows an in-line type transparent conductive film forming apparatus. 
In FIG. 9, a pressure resistant vessel 300 of a gastight structure is 
partitioned into a substrate inlet chamber 201a, a sputtering chamber 
201b, and a substrate outlet chamber 201c. Door valves 202a, 202b, 202c 
and 202d of gastight structures are respectively provided in the substrate 
inlet of the inlet chamber 201a, the boundaries of the chambers 201a, 201b 
and 201c and the substrate outlet of the outlet chamber 201c. Substrate 
conveyors 203a, 203b, 203c are respectively provided in the chambers 201a, 
201b and 201d. Discharge units 204 are respectively connected to the 
chambers 201a, 201b and 201c. The discharge unit 204 has a main discharge 
pump 205 such as a turbo pump, a cryo-pump, an oil diffusion pump, etc. 
and an auxiliary pump 206 such as an oil rotary pump, etc. Nitrogen gas 
supply tubes 207 and 208 for supplying nitrogen gas N.sub.2 into the inlet 
chamber 201a and the outlet chamber 201c are respectively connected to the 
chambers 201a and 201c. An argon gas supply tube 209 for supplying gas in 
vIII group elements of the periodic table such as argon gas Ar into the 
sputtering chamber 201b and an oxygen gas supply tube 210 for supplying 
oxygen gas are connected to the sputtering chamber 201b. In addition to 
the argon gas, xenon gas, neon gas, etc. may be used as for sputtering a 
transparent conductive material. A flow rate controller 211 for 
controlling the supplying flow rate of the argon gas to the sputtering 
chamber 201b to a predetermined value is provided in the argon gas supply 
tube 209. The supplying flow rate of the argon gas Ar to be supplied from 
the argon gas supply tube 209 to the sputtering chamber 201b is always 
held at a predetermined flow rate by the flow rate controller 211. A flow 
rate control valve 212 is provided in the oxygen gas supply tube 210, and 
the supplying flow rate of the oxygen gas O.sub.2 to be supplied from the 
oxygen gas supply tube 210 to the sputtering chamber 201b is controlled by 
the flow rate control valve 212. 
On the other hand, a sampling tube 213 for intaking atmospheric gas 
(mixture gas of argon gas and oxygen gas) in the sputtering chamber 201b 
is connected to the sputtering chamber 201b, and an analyzer 214 for 
analyzing the state of sputtering gas such as oxygen partial pressure, 
etc., in the sputtering chamber 201b is connected to the sampling tube 
213. The output of the analyzer 214 is input to a controller 215, thereby 
controlling a flow rate control valve 212 provided in the oxygen gas 
supply tube 210 to supply predetermined amount of oxygen gas. 
In FIG. 9, substrate heaters 216a, 216b and a heater 217 shown in FIGS. 15 
and 16 are provided in the inlet chamber 201a and the sputtering chamber 
201b. A target 218 formed of a transparent conductive material such as 
ITO, etc., made of oxide and an anode 219 disposed at a position opposed 
to the target 218 are arranged in the sputtering chamber 201b, and a power 
source 220 for supplying a sputtering current is connected to the target 
218 and the anode 219. 
A method of forming a transparent conductive film by the above-described 
in-line type transparent conductive film forming apparatus will be 
described in the case where an ITO film is formed on the surface of a 
glass substrate for a liquid crystal display device. Before a process for 
forming the ITO film, a target 218 made of ITO is first set in the 
sputtering chamber 201b, all the door valves 202a, 202b, 202c and 202d are 
then closed, the air in the chambers 201a, 201b and 201c are discharged by 
the discharge units 204 to evacuate in high vacuum the respective chambers 
201a, 201b, and 210c. Then, nitrogen gas N.sub.2 is supplied from the 
nitrogen gas supply tube 207 into the inlet chamber 201a, the internal 
pressure in the inlet chamber 201a is set to the same pressure as the 
atmospheric pressure, the door valve 202a of the inlet of the chamber 201a 
is then opened, and the glass substrate 222 secured to a carrier 221 is 
set on the substrate conveyor 203a in the inlet chamber 201a. In order to 
maintain the nitrogen gas atmosphere in the inlet chamber 201a during the 
conveying work of the substrate 222 into the inlet chamber 201a, nitrogen 
gas supply from the nitrogen gas supply tube 207 is continued. Then, after 
the door valve 202a is closed, the inlet chamber 201a is evacuated in high 
vacuum state by the discharge unit 204. While the inlet chamber 201a is 
evacuated in high vacuum, the substrate 222 is heated by the heater 216a. 
When the chamber 201a becomes a predetermined pressure (to approx. 
5.times.10.sup.-6 Torr), the door valve 202b between the inlet chamber 
201a and the sputtering chamber 201b is opened, the substrate 222 in the 
chamber 201a is fed onto the substrate conveyor 203 in the sputtering 
chamber 201b, and the door valve 202b is then closed. When the door valve 
201b is closed, next substrate is inserted into the inlet chamber 201a 
similarly to the above. 
On the other hand, when the substrate 222 is fed into the sputtering 
chamber 201b and the door valve 202b is closed, the argon gas Ar and the 
oxygen gas O.sub.2 are supplied from the argon gas supply tube 209 and the 
oxygen gas supply tube 210 into the sputtering chamber 201b, and 
sputtering atmospheric gas of the mixture gas of the argon gas Ar and the 
oxygen gas O.sub.2 is filled in the sputtering chamber 201b. The gas 
pressure of the sputtering atmospheric gas is controlled so that the 
entire pressure becomes 1 to 20 mTorr by continuing the gas supply from 
the argon gas supply tube 209 and the oxygen gas supply tube 210 and 
continuously discharging the atmospheric gas in the sputtering chamber 
201b by the discharge unit 204. In the meantime, the substrate 222 is 
heated by the heater 216b . When the atmospheric gas pressure is 
stabilized, the substrate 222 is conveyed at a predetermined speed by the 
substrate conveyor 203b, a sputtering current is simultaneously supplied 
to the target 218, thereby starting a sputter discharge. 
When the target 218 is sputter discharged by supplying electric energy 
thereto, the ITO sputtered from the target 218 is sequentially deposited 
on the surface of the substrate 222 passing at a predetermined speed under 
the target 218 to form an ITO film having a predetermined thickness on the 
substrate 222. When the substrate 222 completely passes under the target 
218, the sputter discharge is stopped, and the supplies of the argon gas 
Ar and the oxygen gas O2 are stopped as well. Thereafter, the door valve 
202c between the sputtering chamber 201b and the outlet chamber 202c is 
opened, the ITO film forming substrate 222 in the sputtering chamber 201c 
is fed on the substrate conveyor 203c in the chamber 201c, and the door 
valve 202c is closed. On the other hand, the substrate 222 in the inlet 
chamber 201a is fed into the sputtering chamber 201b by opening the door 
valve 202b between the inlet chamber 201a and the sputtering chamber 201b, 
and the door vale 202b is then closed. When the door valves 202b, 202c are 
closed, the sputtering chamber 201b is processed to form an ITO film 
similarly to the above, the ITO film forming substrate 222 fed to the 
outlet chamber 201c is conveyed out by supplying the nitrogen gas N.sub.2 
from the nitrogen gas supply tube 208 into the outlet chamber 201c, 
setting the internal pressure in the outlet chamber 201c to the same as 
the atmospheric pressure, and then opening the door valve 202d. The door 
valve 202d is closed after the substrate 222 is removed, and then the 
outlet chamber 201c is again evacuated in high vacuum. 
In the sputtering apparatus of FIG. 9 described above, the target, the 
anode, etc. to be disposed in the sputtering chamber 201b are attached as 
below. 
In FIGS. 10 and 14, an opening 223 is formed at the sidewall of the 
sputtering chamber 201b, and an openable door 224 made of a copper plate 
for sealing the opening 223 is provided at the sidewall. The target 218 is 
attached to the inner surface of the openable door 224, and a magnet 
(permanent magnet) 225 for generating a magnetic field for confining a 
plasma is attached to the outer surface of the door 224. An anode 219 of a 
frame plate shape made of a conductive metal plate is disposed oppositely 
to the target 218. This anode 219 is supported to the door 224 to be 
adjustably at the position to the target 218 of the inner surface of the 
door 224. 
The supporting structure of the anode 219 to the door 224 will be 
described. A pair of upper and lower hinge members 225 are attached to the 
inner surface of the door 224 so as to be capable of rotatably attaching 
the anode 219, the hinge members 226 are disposed so that its hinge shaft 
sides are directed toward the sputtering chamber 201b, and the stationary 
side hinge pieces 226a are clamped at the door 224. An anode supporting 
member made of an L-shaped steel plate (hereinafter referred to as "a 
hinge side anode supporting member") 227 is attached movably in upward and 
downward directions (longitudinal directions of the target 218) Y and in 
rightward and leftward directions (lateral directions of the target 215) X 
to the outer surface of the movable side hinge piece 226b of the hinge 
member 226. In other words, the hinge side anode supporting member 227 is 
clamped at the vertical plate portion to the movable side hinge piece 226n 
of the hinge member 226 with a bolt 228, and attached to the movable side 
hinge piece 226b. A bolt insertion hole 229 opened at the vertical plate 
portion of the hinge side anode supporting member 227 is formed, as shown 
in FIGS. 11 and 12, in a circular hole having a diameter sufficiently 
larger than that of the shaft portion of the bolt 228, and the hinge side 
anode supporting member 227 is regulated movably in the upward and 
downward directions Y and the rightward and leftward directions X at a gap 
between the bolt insertion hole 229 and the bolt shaft portion by 
loosening the bolt 228. 
On the other hand, horizontally bent pieces 219a and 219b bent 
perpendicularly to the surface of the anode 219 are formed at the upper 
and lower edges of one side of the anode 219 and at the upper and lower 
edges of the other side of the anode 219. Bent pieces 230a formed at the 
upper and lower edges of one side of the anode 219 are supported, as shown 
in FIG. 11, to the horizontal plate portion of the hinge side anode 
supporting member 227 through an insulation porcelain 231, and clamped 
fixedly by bolts 232a, 232b. In other words, the insulation porcelains 231 
are buried with nuts 231a, 231b in a state insulated from each other at 
both ends. One end side of the porcelain 231 is clamped fixedly at the 
horizontal plate portion of the hinge side anode supporting member 227 
with a bolt 232a, and the bent piece 219a of the anode 219 is clamped 
fixedly at the other end side of the porcelain 231 with a bolt 232b. A 
bolt insertion hole 230 opened at the bent piece 219a is formed in a long 
hole as shown in FIGS. 11 and 13, and the anode 219 is regulated movably 
in the forward and reverse directions (in a direction separate from or 
contact with the target 218) by loosening the bolt 232b. In this 
embodiment described above, a bolt insertion hole 233 opened at the 
horizontal plate portion of the hinge side anode supporting member 227 is 
also formed in a long hole as shown in FIG. 11. Thus, the anode 219 can be 
regulated movably in forward and reverse directions by loosening the bolt 
232a clamped at the porcelain 231 to the hinge side anode supporting 
member 227. 
Stationary side anode supporting members 235 made of L-shaped steel plates 
are attached movably in forward and reverse directions to the bent pieces 
219b formed at the upper and lower edges of the other side of the anode 
219 through insulation porcelains 234. The porcelains 234 are buried 
similarly to the porcelains 231 described above in a state insulated from 
each other at both ends. The one end side of the porcelain 234 is clamped 
at the horizontal plate portion of the stationary side anode supporting 
member 235 with a bolt 236a, and the bent piece 219b of the anode 219 is 
clamped at the other end side of the porcelain 234 with a bolt 236b. The 
stationary side anode supporting member 235 is clamped at the openable 
door 224 at the vertical plate portion with a bolt 237 to be detachably 
attached to the openable door 224, and the anode 219 is supported to the 
door 224 by the stationary side anode supporting member 235, the hinge 
side anode supporting member 227 and a hinge member 226. In FIG. 14, an 
engaging hole 238 of the bolt 237 for clamping the vertical plate portion 
of the stationary side anode supporting member 235, is provided at the 
door 224 is formed at the door 224. Bolt insertion holes (not shown) 
opened at the horizontal plate portions of the bent piece 219b and the 
stationary side anode supporting member 227 are both formed in long holes, 
and the stationary side anode supporting member 235 is regulated movably 
in forward and reverse directions Z to the anode 219 by loosening any of 
the bolts 236a, 237a. A bolt insertion hole 239 (FIG. 5) opened at the 
vertical plate portion of the stationary side anode supporting member 235 
is formed in a circular shape having a diameter sufficiently larger than 
that of the shaft portion of the bolt 237, and the stationary side anode 
supporting member 235 is regulated movably in upward and downward 
directions Y and rightward and leftward directions X by loosening the bolt 
237. 
More specifically, the anode 219 is attached movably in upward and downward 
directions Y and rightward and leftward directions X to the movable side 
hinge piece 226b of the hinge member 226 for securing the hinge side anode 
supporting member 227 to the openable door 224, and attached movably in 
the upward and down10 ward directions Y and rightward and leftward 
directions X at the stationary side anode supporting member 235 to the 
door 224 to regulate the target 218 longitudinally and laterally. Further, 
the gap to the target 218 can be regulated by relatively movably 
regulating the hinge side anode supporting member 227 and the stationary 
side anode supporting member 235 relative to the anode 219 in forward and 
reverse directions Z. The anode 219 can be rotated separately from or 
contact with the door 224 as shown in FIG. 14 by removing the bolt 237 for 
clamping the stationary side anode supporting member 235 at the door 224 
since the hinge side anode supporting member 235 for supporting one side 
of the anode 219 is attached to the door 224 through the hinge member 226. 
In the sputtering apparatus of the embodiment described above, the anode 
219 is supported to be regulated at the position to the door 224 for 
attaching the target 218. Accordingly, the position of the anode 219 can 
be regulated in longitudinal directions (Y directions) and lateral 
directions (X directions) of the target 218 in directions (Z directions) 
for separating from or contact with the target 218 in the state that the 
door 224 is opened as shown in FIG. 10 while directly checking the 
position of the anode 219 to the target 218. Therefore, the position of 
the anode 219 can be readily regulated with satisfactory operability. 
In the sputtering apparatus, the anode 219 is rotated to be separated from 
or contact with the door 224. Accordingly, when the target 218 is 
replaced, the anode 219 can be retracted to the position not for 
disturbing the replacement of the target as shown in FIG. 14, and hence 
the anode 219 is supported to the door 224 attached with the target 218, 
but the replacement of the target 218 can be also facilitated. 
In the embodiment described above, the anode 219 can be regulated not only 
in the longitudinal directions (Y directions) and the lateral directions 
(X directions) of the target 218 but in the direction for separating from 
or contact with the target 218 (Z directions). However, the factors for 
affecting influences largely to the discharge state are the positional 
relationship between the erosion 239 generated particularly at the target 
218 and the opening edges of the anode 219, and the change of the 
discharge state due to the interval between the target 218 and the anode 
219 can be regulated by controlling the discharge current flowing between 
the target 218 to become the cathode electrode and the anode 219. 
Therefore, the anode 219 may not be regulated at the position in the 
directions (Z directions) for separating from or contacting with the 
target 218. 
In the embodiment described above, the anode 219 is supported to the door 
224 through the hinge side anode supporting member 227 and the hinge 
member 226, the stationary side anode supporting member 235. However, the 
structure in which the anode 219 is supported to be regulated at the 
position to the door 224 is not limited to the particular embodiment, but 
an arbitrary mechanism may also be employed. 
A substrate heater is provided in addition to the heater in the sputtering 
chamber 201b shown in FIG. 9 described above. In other words, as shown in 
FIGS. 16 and 16, the sputtering apparatus has means for heating the 
substrate 222 during film forming to a predetermined temperature. More 
specifically, a substrate heater 241 for heating a substrate 222 to be 
formed with a film while passing a film forming portion 240 is provided in 
the vicinity of the anode 218 of the film forming portion 240 in the 
sputtering chamber 201b. The substrate heater 241 is provided around an 
opening for passing sputtering particles of the anode 218 at the surface 
of the anode 218 opposed to the substrate 222. The substrate heater 241 
may be, for example, an infrared ray heater, and is connected to a heater 
controller (not shown). 
The sputtering apparatus is provided to heat the substrate 222 conveyed in 
the sputtering chamber 201a by the substrate carrier 221 to a 
predetermined temperature in the step of passing the heater 216a and to 
heat the substrate 222 to the predetermined temperature in case of passing 
the film forming portion 240. Accordingly, the substrate 222 passing the 
film forming portion 240 is formed with a film by sputtering while heating 
by the radiation heat from the substrate heater 241 provided at the anode 
219 of the film forming portion 240. 
Therefore, according to the sputtering apparatus described above, even if 
the substrate 222 heated by the heater 216b is lowered at its temperature 
by the radiation of the heat during moving to the film forming portion 
240, the substrate 222 can be heated to be raised at its temperature by 
heating it by the substrate heater 241 at the film forming portion 240. 
Accordingly, the substrate temperature during film forming while passing 
the film forming portion 240 can be maintained at the temperature for 
preferably depositing sputtering particles to form a film of high quality 
on the substrate by controlling the temperature of the substrate heater 
241. 
In the embodiment described above, the substrate heater 241 of the film 
forming portion 240 is provided on the surface of the anode 219 opposed to 
the substrate 222. However, the invention is not limited to the particular 
embodiment. For example, the substrate heater 241 may be provided between 
the anode 219 and the substrate 222. 
In the embodiment described above, the substrate heater 241 for heating the 
substrate 222 during film forming is provided in the film forming portion 
240. However, the substrate heater 241 may also be provided to be moved 
together with the substrate 222, and the structure will be shown in FIG. 
17. 
This substrate heating means has a substrate heater 242 provided on a 
substrate carrier 221 for conveying a substrate 222 for heating a 
substrate 222 during film forming. The substrate carrier 221 is formed 
with a substrate holding recess 245 for holding to contain the substrate 
222 in a carrier body 244 having wheels 243 running on rails (not shown), 
and the two substrate 242 is provided in the deep bottom of the recess 
245. In this embodiment, two film forming substrates A are held 
back-to-back on the substrate carrier 221 and films are simultaneously 
formed on the two substrates 222 in a sputtering apparatus. The substrate 
carrier 221 is formed with the substrate holding recesses 345 on both side 
surfaces of the carrier body 224, and the substrate heaters 242 are 
respectively provided in the deep bottoms of both the recesses 245, or 
buried in the bottom walls of both the recesses 245 (in the partition 
walls for partitioning the recesses 245) to be held in the recesses 245 to 
commonly heat the two substrate 222 held in the recesses 245. The 
substrate heater 242 is connected, for example, to a heater controller 
through a reel-wound cable (not shown) fed out or wound as the substrate 
carrier 221 is moved. 
More specifically, in the embodiment described above, the substrate heater 
242 is provided in the substrate carrier 221 for conveying the substrate 
222 to heat the substrate 221 during film forming. According to the 
embodiment, since the substrate 222 conveyed by the substrate carrier 221 
can be always heated to a predetermined temperature during conveying, the 
substrate temperature can be maintained at the temperature for preferably 
depositing the sputtering particles on the substrate during film forming 
to form a film of high quality. According to the substrate heating means 
of FIG. 17, the heater 216b provided in the sputtering chamber 201b of the 
sputtering apparatus shown in FIG. 15 can be eliminated. 
Additional advantages and modifications will readily occur to those skilled 
in the art. Therefore, the invention in its broader aspects is not limited 
to the specific details, and representative devices, shown and described 
herein. Accordingly, various modifications may be without departing from 
the spirit or scope of the general inventive concept as defined by the 
appended claims and their equivalents.