JPS5996267A - Magnetron sputtering device - Google Patents

Abstract

PURPOSE:To make uniform a distribution of the thickness of a thin film formed on a substrate over a wide area by providing positive electrodes for adjusting the region where plasma is generated by glow discharge along the short side of a target near the surface thereof. CONSTITUTION:Gas is introduced into a vacuum vessel 1 after the inside thereof is evacuated to vacuum and the gas is maintained under a prescribed pressure by adjusting the rate of evacuation. Positive potential is impressed by a power source 17 on electrodes 11, 11' provided along the short side of a target 6 near the surface thereof and a negative high voltage is impressed on a cathode 7 by a power source 14. A substrate 5 is moved over the target plate 6 by a transfer device 4 while sputtering is executed, so that a sputtered film is formed on the substrate 5. Then, the sputtering speed near the short edge of the plate 6 is increased by the electrodes 11, 11' and the film thickness of the substrate corresponding to said part is increased, whereby the uniform distribution of the film thickness is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flat plate type magnetron sputtering apparatus, and particularly to a flat plate type magnetron sputtering apparatus suitable for forming a thin film of uniform thickness on the surface of a substrate.

Conventionally, a flat plate type magnetron sputtering apparatus includes a vacuum vessel, an evacuation means for evacuating the vacuum vessel to a predetermined pressure, a rectangular flat target provided in the vacuum vessel, and a device that approaches the back surface of the target and surrounds it. A magnetic device consisting of a frame-shaped outer peripheral magnet provided along the long side, and a central magnet provided along the long side in the center thereof, and a direction that faces the surface of the target and crosses the long side of the target. The apparatus is comprised of a transfer device for transferring a substrate to a substrate, a means for supplying gas into the vacuum container, and a power source for applying a voltage between the vacuum container and the cuget. Such a flat plate type magnetron sputtering device reduces the pressure of a vacuum container to a predetermined degree of vacuum using an exhaust means, and then injects an inert gas such as argon or a reactive gas such as a mixture of argon gas and oxygen gas into the vacuum container. It is introduced at a constant flow rate and evacuated with a constant exhaust H1 to maintain the vacuum in the vacuum chamber at 0-2 to -70-3 Torr. A voltage is applied to generate a discharge, and a magnetic device focuses the plasma of the glow discharge on the surface of the target by the lens action of the magnetic field, thereby sputtering the target material, and transporting it facing the surface of the target by a transfer device. It was used to form a thin film on the surface of a substrate.

Thin film formation by magnetron sputtering allows sputtering of a target at high speed and continuous thin film formation, resulting in high productivity in thin film formation, and is therefore used for the formation of various thin films, especially indium oxide, etc. Metal oxide film whose main component is tin oxide, chromium,
It is useful for forming metal films such as aluminum and molybdenum.

However, when forming a thin film using the above-mentioned flat plate sputtering apparatus iT, the thickness of the thin film is almost uniform in the substrate transport direction, but is uneven in the direction perpendicular to the substrate transport direction (hereinafter referred to as the width direction of the substrate). There was a drawback that it was uniform.

The present invention has been made to solve fW problems of the above-mentioned flat plate type sputtering apparatus, and the present invention includes a vacuum vessel, an exhaust means for evacuating the vacuum vessel to a predetermined pressure, and a vacuum vessel provided in the vacuum vessel. a magnetic device consisting of a rectangular flat plate target, a frame-shaped outer peripheral magnet provided close to the back surface of the target and along its periphery, and a central magnet provided in the direction of the long side of the center; a transfer device for transferring a substrate onto the surface of the target in a direction transverse to a long side of the target; a means for supplying gas into the vacuum container; and between the vacuum container and the target. In a magnetron sputtering apparatus consisting of a power supply for applying a voltage to the
The magnetron sputtering device EL is characterized in that at least one electrode maintained at a positive potential for adjusting a plasma source region due to glow discharge is provided near the surface of the target.

In the present invention, the electrode held at a positive potential is placed between the target and the substrate, preferably on the substrate side separated from the surface of the target by 7 mm to JQm'm,
Further, it is provided within 3 Q m 61, preferably within /On+ 711 outward from the short side of the target.

Further, in the present invention, the electrode held at a positive potential is 10 to
Preferably, a voltage of V is applied.

Furthermore, in the present invention, Ti held at the positive potential
Jdzt is usually made of metal such as stainless steel, copper, or aluminum, and its shape can be round, pipe, plate, or
or a letter of intent.

According to the present invention, at least one electrode is provided along both short edges of the target and near the surface of the target, and is held at a positive potential to adjust the plasma generation area due to glow discharge. It is possible to uniformly generate plasma in the width direction of the substrate, increase the spunter speed near the short edge of the target, increase the coating formed on the part of the substrate corresponding to that part, and increase the thickness of the substrate. It is possible to prevent the formed film from deteriorating at the edges in the width direction, and to enlarge the window region of the film thickness in the width direction of the substrate.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. A substrate transfer device l capable of supporting and transferring both edges of a glass substrate is provided in a vacuum container, and a gas that is continuously photographed by this transfer device l is provided. Length 2127 in the transport direction towards the path of the substrate
A rectangular alloy target plate A of 90% by weight indium and 10% by weight tin with a length of mm and a direction perpendicular to the transport direction is provided on the cathode 7, and a target plate O is provided near the back surface of the target plate O and around it. A magnetic device 10 is provided which includes a frame-shaped outer peripheral magnet g provided along the frame and a central magnet w provided in the long side direction at the center thereof.

As shown in Fig. 2, the magnetic device 10 has a magnet groove on the outer periphery of the length in the long side direction x length in the short side direction x width lg Omm x 101 mm.
The size is X mm, the target plate 6 side is the N pole, the opposite side is the S pole, and the strength of the magnetic field near the N pole of the magnet is 73
00 Gauss magnet, and the central magnet 9 has a length in the long side direction x width of 370 Tnm x /2 mm, and the target plate O side is the S pole.

The opposite side is the N pole, and the strength of the magnetic field near the S pole of the magnet is 7 g.
00 Gauss, and the S pole of the outer peripheral magnet and the central magnet 9
It is connected to the ON pole by a yoke/λ.

In addition, cooling water is introduced into the cathode 7 where these magnetic devices 10 are provided through the water guiding lower 1 υ1, and is drained from the drainage lower and circulated to cool the cathode, the magnetic device 10, and the target plate B. Cool. 10 minutes from the surface of the Talget board Otsu
Electrodes //, /// consisting of a pair of stainless steel bars with a length of 30 mm and a diameter of 2' mmφ are installed at a position 2.2 mm from the center in the longitudinal direction of the target plate and μ.

Further, a vacuum preliminary chamber 3 is connected to the uppermost side of the vacuum container for supplying glass substrates, and a vacuum preliminary chamber 3 is connected to the lowermost side to take out the glass substrate on which a thin film has been formed. Substrate transfer devices lI, t, 1ltt are provided in the vacuum preparatory chambers 2 and 3, respectively, and movable gate valves/311. /3111 is installed, and valve /J''' is installed.

The vacuum vessel/and the vacuum preparatory chambers 2 and 3 are equipped with exhaust systems connected to exhaust ports/l, 'rt, and 3t provided at the bottom of each.
(Figure omitted) allows for exhaust. Open the gate valve /3/, place the glass substrate S on the substrate transfer device 4Z/ in the vacuum preliminary chamber 2, close the gate valve /3/, and open the vacuum container / and the vacuum preliminary chambers 2 and 3. Reduce the pressure, open Kate Valve/311, and enter the vacuum preliminary chamber! Move the glass substrate j inside and close gate valve/3〃.

The evacuation system of the vacuum container is a combination of a Talio bomb and a rotary pump (not shown), and once the inside of the vacuum container is 10-
Evacuate to a vacuum level of 6 Torr, and then flow a mixed gas of argon gas of 10% by volume and oxygen gas of 10% by volume from the gas pipe/S that supplies gas into the vacuum container/.
10o SCCM (stand cubic centimeter 7 minutes) is supplied into the vacuum container/inside, and the degree of vacuum in the vacuum container/in is adjusted to approximately 3 x 10-3 Torr in balance with the evacuation speed with the exhaust thread.
A voltage of /lO■ is applied to the electrodes //, /// with respect to the vacuum vessel / by the power supply /7, and the voltage is maintained at a constant pressure of 0. IOA
When electricity is applied and the power supply is turned on, the cathode 7 insulated with the insulator from the vacuum vessel has a voltage of -110 with respect to the vacuum vessel.
While sputtering was performed by applying a voltage of 0.0 cm, the glass substrate was moved over the target plate by the transfer device 1, and an indium oxide thin film containing tin oxide was formed on the surface of the glass substrate. The glass substrate S with the thin film attached in this way is further transferred by the transfer device DA, and the gate valve/
3//l opens the substrate transfer device l1l in the vacuum preliminary chamber 3
The gate valve /31 was closed, the gel valve /J ///l was opened, and the sample of the glass substrate j on which the thin film was deposited was taken out to the outside.

The relationship between the film thickness distribution in the width direction of the sample thus obtained and the target plate A and the magnetic device 10 is shown in FIG.

The variation in the thickness of the thin film formed on the surface of the glass substrate S is 5%.
The effective width of sump/l within was 32Cjtn.

Next, sputtering was performed under exactly the same conditions as in the example except that the electrodes were removed to obtain a comparative sample.

The relationship between the film thickness distribution in the width direction of this comparison sample and the target plate O and the magnetic device 10 is shown in FIG. The effective width of the specific axis sample in which the thickness of the thin film formed on the surface of the glass substrate was within 5% was 2110 m, which was also smaller than the effective width of the sample according to the present invention.

As is clear from the above, the electrodes // and //l of the magnetron sputtering apparatus according to the present invention increase the sputtering speed near the short edge of the substrate and increase the film formed on the part of the substrate corresponding to that part. However, since it can be changed to obtain a uniform film thickness distribution, the film thickness distribution of the thin film formed on the substrate surface can be made uniform over a wide area, making it possible to increase the production amount of the product. .

[Brief explanation of drawings]

The drawings show the implementation of the present invention, and FIG. 7 is a longitudinal cross-sectional view of the sputtering device, and FIG. A diagram showing the relationship between the target plate and the magnetic device. FIG. 3 is a diagram showing the relationship between the target plate and the magnetic device and the film thickness distribution in the width direction of a sample manufactured by a conventional magnetron sputtering device. /: Vacuum container, 21,3': Exhaust port, gear, transfer device. S Niglass substrate, Otsu: Flat plate targetft. g=outer magnet, 9: center magnet, /Huffll: electrode. /l: Power supply, /7: Power supply Figure 2 Surinachi Ebe LL CC-n-) Figure 3 Board 1st f4 (cryc) 355

Claims (1)

[Claims] A magnetic device consisting of a plate target, a frame-shaped outer peripheral magnet provided close to the back surface of the target along its periphery, and a central magnet provided in the direction of the long side of the medium heat; a transfer device for transferring a substrate in a direction across a long side of the target, facing a surface; means for supplying a gas into the vacuum vessel; and a voltage between the vacuum vessel and the target. a magnetron sputtering apparatus comprising: a power supply for applying power; at least one electrode held at a positive potential along a short side of the target and near the surface of the target for adjusting a plasma generation region by glow discharge; A magnetron sputtering device characterized by being provided with.