JPS62118524A - Manufacture of semiconductor element - Google Patents

Abstract

PURPOSE:To enable the lift-off processing with excellent workability and reliability to be performed while forming thick deposit metallic layer together with thin resist film by a method wherein deposit metallic layer comprising metallic material for interconnection is formed on a resist mask formed on a substrate and then the unnecessary part of deposit metallic layer is removed by lifting off an adhesive film. CONSTITUTION:A resist mask 2 1mum thick with overhang ends is formed on a substrate 1 and then a deposit metallic layer 3 comprising metallic material for wiring around 0.6mum thick is deposited. Next a bonding film 5 is pressure- fixed on the substrate 1. Then the substrate 1 is fixed by vacuumizing or using a fixture and then the bonding film 5 is lifted off in the arrow direction. Through these procedures, the connecting part 4 between the first and the second deposit metallic films 3a, 3b is completely cut of and the second deposit metallic layer 3b is lifted off together with the bonding film 5. Later the residual resist mask 2 is removed by melted cleaning or plasma processing to form a wiring pattern by the first deposit metallic layer 3a.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a semiconductor device, and particularly in a process for manufacturing a device using a compound semiconductor such as GaAa.
The present invention relates to a method for forming a pattern of a metal film on a substrate.

[Conventional technology]

Conventionally, the method of patterning a metal film on a substrate is as follows:
There is a so-called lift-off method in which the resist coat and the metal film other than the wiring portion are removed at the same time.

As is well known, this lift-off method is often used to form fine patterns or metal patterns that are difficult to chemically etch.

This conventional example will be explained below based on FIG. 2. First, the same figure (
As shown in a), a resist film 2 is formed on a substrate 1 to a predetermined thickness. Next, as shown in FIG. 2B, the resist film 2 is patterned to form a resist mask 2a. Next, when metal is laminated to a predetermined thickness on this sample, the first deposited metal layer 3 is formed on the substrate 1, as shown in the same figure (c>).
Further, second deposited metal layers 3a are respectively formed on the resist masks 2a.

Thereafter, when the sample is immersed in a lift-off solvent, the resist mask 2a is dissolved and the second deposited metal layer 3a is peeled off, resulting in a predetermined wiring pattern as shown in FIG. 3(d).

[Problem that the invention seeks to solve]

However, in the above-mentioned conventional example, a deposited metal layer is required to facilitate and ensure the lift-off process, and the thickness of the resist that can be uniformly coated is limited to approximately 1 μm.

For this reason, when the thickness of the deposited metal layer exceeds 5000, the first deposited metal layer 3 on the substrate 1 will be removed as shown in FIG.
A connection portion 4 is formed between the resist mask 2a and the second deposited metal layer 3a on the resist mask 2a. Therefore, during lift-on, there is a problem in that the infiltration of the solvent into the resist mask 2a becomes poor, and even if a process such as ultrasonic cleaning is applied, a long time is required for patterning, resulting in a decrease in workability.

Further, when applying mechanical shock such as ultrasonic waves, if the substrate is made of QaAs, which has poor impact resistance, there is a high probability of breakage, which is unfavorable from the viewpoint of reliability in the process.

Therefore, the present invention solves the above-mentioned problems, makes it possible to make the resist film thickness within the range of 1 μm that can be formed uniformly, and makes it possible to form a deposited metal layer thicker than before, with excellent workability and reliability. It is an object of the present invention to provide a method for manufacturing a semiconductor device that undergoes a lift-off process.

[Means for solving problems]

The method for manufacturing a semiconductor device according to the present invention includes the steps of (a) forming a resist mask having a predetermined shape of a no-e turn on a substrate, and then forming a deposited metal layer consisting of a metal layer for wiring; ) Thereafter, the process includes the steps of: (c) peeling off the adhesive film; and (c) peeling off the adhesive film.

[For production]

As described above, according to the present invention, a desired resist mask is formed on a substrate, and then a deposited metal layer made of a metal material for wiring is formed. The metal layer! , and a second deposited metal layer is formed on the resist mask, respectively, and is removed by a lift-off method.

Further, since the adhesive film is pressed and adhered to the substrate, the adhesive film is brought into close contact only with the second deposited metal layer, and at this time, the resist mask acts to relieve mechanical stress on the substrate.

Further, when the adhesive film is peeled off, only the second deposited metal layer is peeled off at the same time.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail based on FIG. ′-! First, as shown in FIG. 5A, a resist mask 2 with a thickness of 1 μm is formed on a substrate 1 by patterning so that the end portion has an overhang shape, and then a deposited metal layer 3 made of a metal material for wiring is formed. 0.611m thick. In this case, on the substrate 1 is a first deposited metal layer 3a for a wiring pattern (pattern width is about 1 μm), and on the resist mask 2 is a second deposited metal layer 3b to be removed in a later process. The numeral 4 indicates the first and second deposited metal layers 3a.

This is the connection part of 3b.

Next, as shown in the same figure (b), using an adhesive film (Nitto's Danpronchi I, [)iaco's Electronte, -pu, etc.) 5, a roller 7 made of rubber or the like is placed with the adhesive layer 6 on the substrate 1 side. is moved in the direction of arrow A while applying pressure in the direction perpendicular to arrow B, and the adhesive film 5 is pressed tightly onto the substrate 1. At this time, the mechanical stress applied to the substrate 1 from the vertical if direction is alleviated by the interposition of the resist mask 2. Then, as shown in FIG. 3(c), the substrate 1 is fixed by vacuuming or using a fixing jig (not shown),
Peel off the adhesive film 5 in the direction of the arrow. Through this treatment, the connection 4 between the first and second deposited metal layers 3a and 3b is completely severed, and the second deposited metal layer 3b is peeled off together with the adhesive film 5. In the figure, the dotted line above the break line and the solid line following it schematically represent the adhesive film 5 after peeling.

Furthermore, the resist mask 2 and the second deposited metal layer 3b are
The resist mask 2 is peeled off from the boundary ih+ as shown in the 0 part, or the resist mask 2 is removed from the second deposited metal layer 3 as shown in the 0 part.
It adheres closely to b and peels off as if the layer is torn apart. Further, since the adhesive layer 6 and the first deposited metal layer 3a do not come into close contact with each other due to the thickness of the resist mask 2 (1 melting phase degree), in the peeling process, the second deposited metal layer 3a) What happens is that only f13b is peeled off.

Here, the pressure adhesion treatment and the peeling treatment of the adhesive film 5 can be performed continuously by using a roller-type adhesive film as shown in FIG. 4(d). In other words, the adhesive film 5 is pressed and brought into close contact with the substrate portion 1a on which the deposited metal layer 3 has been formed in the direction of the arrow via the roller 7 in the direction of the arrow, while the winding film 5 rotates in conjunction with these in the same direction. By rolling up the adhesive film 5 after being pressed into close contact with the roller 5b, the peeling process is continuously performed without generating air bubbles between the adhesive film 5 and the substrate 1.

Thereafter, the remaining resist mask 2 is removed by dissolving and cleaning or plasma processing, and an ffM pattern formed by the first deposited metal layer 3a is obtained.

As described above, according to the present invention, the second deposited gold F4 layer 3b to be lifted off is peeled off in close contact with the adhesive film 5, so that re-adhesion of metal is avoided and it can be easily recovered. can.

In addition to a single crystal substrate of a compound semiconductor such as QaAs, the substrate 1 may also be a substrate on which an insulating film such as a Si0g film, Sl, N4 film, etc. is laminated. can be widely applied.

〔Effect of the invention〕

As explained above in detail in #Ij1, and as shown in 1j, according to the present invention, in order to remove the deposited metal layer formation and unnecessary portions (second deposited metal layer) by pressing the adhesive film into close contact with each other and peeling it off, This deposited metal layer is within the range of (film thickness of deposited metal layer) (film thickness of nost mask), in other words, maximum 1
μ? It can be formed as thick as approximately n.

Therefore, there is an effect that a low-resistance wiring layer having a root resistance hi: of 50 inΩΔ1 or less can be obtained.

In addition, even if the deposited metal layer is formed thickly, there is no need for long-time immersion or ultrasonic treatment to improve the N-moisture properties of the lift bath agent, which is required in the conventional method. It has the effect of suppressing stress and improving L2 and work (11).

Furthermore, in order to effectively utilize the lift-off method, it is possible to easily form even a coarse fine pattern of 10M, making it highly valuable for industrial use1.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a cross-sectional view of a process for explaining one embodiment of the present invention;
The figure is a process cross-sectional view explaining the conventional example, and FIG. 3 is a main part cross-sectional view explaining the drawbacks of the conventional example. DESCRIPTION OF SYMBOLS 1... Substrate, 2... Resist mask, 3... Deposited metal layer, 3a... First deposited metal layer, 3b... Second
Deposited metal layer, 5...adhesive film, 6...adhesive layer, 7...roller. Procedural amendment

Claims (1)

[Claims] (1) In a method of manufacturing a semiconductor device in which a wiring pattern of a metal film is formed on a substrate, (a) a resist mask having a pattern of a predetermined shape is formed on the substrate, and then a deposited metal made of a metal material for wiring is formed. A method for manufacturing a semiconductor device, comprising the steps of: forming a layer; (b) then press-fitting an adhesive film onto the sample; and (c) peeling off the adhesive film.