JPS62294167A - Copper film manufacturing method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] 3. Detailed description of the invention [Industrial application fields] The present invention relates to a method for manufacturing a copper film.

[Prior Art] Generally, when a metal element is vacuum-deposited on a glass substrate, the adhesive force is small for metals that are difficult to oxidize, such as Au and Ag.
It is large for metals that are easily oxidized such as Cr, N1-CrXT1, and N1n. Copper has an adhesive strength intermediate between these elements. For this reason, when it is desired to bond copper to a glass substrate with high strength, a base layer such as a C vapor deposition layer with a strong adhesive force is formed on the surface of the glass substrate, and copper is vapor-deposited thereon. However, this method has the disadvantage of poor productivity and economy because an extra underlayer is formed.

Therefore, as a means of increasing the adhesion strength of the copper vapor deposited layer without forming an extra underlayer, the substrate temperature is increased and copper is vacuum vapor deposited using resistance heating or an electron gun.

[Problems to be Solved by the Invention] However, when vacuum deposition is performed by evaporating copper using resistance heating or an electron gun, the degree of vacuum fluctuates due to changes in the flow rate of exhaust gas, making it difficult to form a copper film with a uniform thickness. difficult to form stably. Also, those that perform vapor deposition at a high substrate temperature have a substrate structure.

It cannot be used if the acid substance does not have sufficient heat resistance.

Furthermore, from the viewpoint of the vacuum evaporation process, it is preferable that the temperature during evaporation be lower.

The present invention has been made in view of these points, and allows copper to be easily vapor-deposited at low temperatures with sufficiently high adhesion strength without forming any base layer on the glass substrate. A method for manufacturing a copper film is provided.

[Means for Solving the Problems] The present invention provides that 1% by weight or more of AI is applied to a glass substrate as an object to be deposited.
This is a method for producing a copper film, characterized in that the copper film is formed by sputter deposition using a target made of copper containing .

Here, the present invention can be applied to the formation of various electrodes, conductor wiring, printed circuits, flexible printed circuits, and the like.

In addition, the amount of Al in the steel constituting the target is 1 to 1
It is preferable to set it in the range of 0% by weight.

The reason for setting the amount of Al to be 1% by weight or more is that the amount of Al exceeds 1% by weight, as is clear from the characteristic line I of the relationship between the adhesive strength of the copper film and the amount of Al in Cu shown in the figure. This is because it has been experimentally confirmed that sufficient adhesive strength can be obtained from contact. The reason why the amount of AI is less than 10% by weight is to take into consideration the fact that if this value is exceeded, the properties of the copper film (eg, surface reflectance, solubility in etching solution) are lost. Of course, the value may be 10% by weight or more as long as such changes in the properties of the copper film are sufficiently taken into account.

[Function] According to the method for manufacturing a copper film according to the present invention, a copper film is formed on a glass substrate by sputter deposition using a target made of copper containing 1% by weight or more of AI. It is possible to form a film with a dense structure and high adhesive strength. Furthermore, since the film is dense, defects such as adsorption of water or nitrogen do not occur, which helps improve adhesive strength. As a result, copper can be easily vapor-deposited at low temperatures and with sufficiently high adhesive strength without forming any underlayer on the glass substrate.

[Example] Examples of the present invention will be described below.

A glass substrate made of 3 inch Φ x 1.6 M high glass transition point glass (Corning's product name, Soder Lime 705B) was immersed in a chromic acid mixture, then rinsed with pure water and cleaned by rubbing with a sponge while pouring pure water. and dried automatically. The glass substrate pretreated in this way was placed in a sputtering device equipped with a rotating dome-shaped substrate holder (CNC Co., Ltd. product name: AST-601, DC flat plate bipolar sputtering device), and an 8×10 Sputtering was performed under the following conditions under a reduced pressure of -6 Torr to form a copper film with a thickness of 1 μm.

In order to investigate the adhesive strength of the copper film formed in this way, we performed a peel test using cellophane tape and found that the substrate temperature was 1.
It was found that the film did not peel off at both temperatures of 00°C and 200°C and had sufficiently high adhesive strength.

In addition, when a weight test was conducted using the aforementioned copper film as a 580-meter fine pattern, as shown in Fig.
It was found that the value was greater than or equal to CKg/d, which was an extremely good result.

Vacuum level during work: 4xlO' Torr times
Rotation speed 20/min RPM setting Temperature 90℃ 1
0 minute sputtering time 30-35 minutes
Target: 8 inches x 8 mm Target material: Cu+AI (1 to 10%) [Effects of the invention] As explained above, according to the method for producing a copper film according to the present invention, no base layer is formed on the glass substrate. Furthermore, copper can be easily deposited at low temperatures with sufficiently high adhesion.

[Brief explanation of the drawing]

FIG. 1 is a characteristic diagram showing the relationship between the adhesive strength of a copper film and the amount of AI in Cu.

Claims (2)

[Claims] (1) A method for producing a copper film, which comprises forming a copper film on a glass substrate as a deposition target by sputter deposition using a target made of copper containing 1% by weight or more of Al. (2) 1 to 10% by weight of A in the copper constituting the target
Claim 1 characterized in that l contains
The method for producing a copper film described in Section 1.