JPH0472730A - Wiring formation process - Google Patents

Abstract

PURPOSE:To cut down the job numbers and manhours for enabling the wiring to be formed in high throughput thereby cutting down the manufacturing processes and the cost of the wiring to be used for integrated circuit etc. CONSTITUTION:A region whereon a wiring is to be formed is irradiated and swept with energy lines for evapotranspirating the atoms on the surface of a silicon oxide film 2 to form an activated layer 3. When aluminum is deposited by vapor deposition process, an aluminum wiring 5 is selectively formed on the activated layer 3 and the time required for the wiring formation equals to the sweeping time of the energy lines 4 and the formation time of the wiring thin film while the sweeping time of the energy lines 4 can be cut down shorter than that when the laser vapor deposition process is adopted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of forming wiring constituting an integrated circuit or the like.

[Conventional technology]

Conventionally, methods for forming wiring include methods using photolithography and direct drawing of wiring using laser vapor phase epitaxy (37th Applied Physics Association Lecture Preliminary).
E 496 pages 29a-ZE8).

[Problems that Hatsuho is trying to solve]

The conventional method using photolithography described above requires six steps: film formation, resist coating, exposure, development, etching, and resist removal, in addition to photomask production, which is time-consuming and costly. There is. Furthermore, the method of directly drawing wiring using laser vapor deposition has the disadvantage that the drawing speed is limited in order to form wiring having a desired thickness, and the throughput is low.

[Means to solve the problem]

The wiring forming method of the present invention involves irradiating a line of energy to a wiring region of an inactive substrate for depositing a thin film for wiring using selective vapor deposition to coat the surface of the substrate.
This method is characterized in that wiring is then selectively formed in the region irradiated with a single line of energy by vapor phase growth.

[Effect]

For example, when an aluminum film is formed using dimethylaluminum hydride by selective vapor phase chemical growth, the aluminum film is deposited on silicon but not on the silicon oxide film, providing selectivity ( Proceedings of the 50th Japan Society of Applied Physics Academic Conference 631 pages
29p-D-1). When this dimethylaluminum hydride is used, when a silicon oxide film is irradiated with a single energy beam, atoms on the surface of the silicon oxide film are removed, and silicon dangling occurs even on the surface of the inert silicon oxide film due to the selective deposition described above. It was newly discovered that bond is generated. At this time, the area irradiated with the single energy line becomes activated for film deposition, and an aluminum film can be selectively formed in the area irradiated with the single energy line by vapor phase chemical growth.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a sectional view of a substrate formed by main steps in an embodiment of the present invention. This embodiment exemplifies a case where the present invention is applied to the formation of wiring in a silicon integrated circuit.

Using a standard integrated circuit manufacturing method, the structure shown in FIG. 1(a) before wiring is formed (the element region formed on the substrate is not shown). In the figure, 1 is a silicon substrate and 2 is a silicon oxide film. Next, as shown in FIG. 1(b), apply energy I to the area where wiring is to be formed.
14 is swept while irradiating the silicon oxide film 2, atoms on the surface of the silicon oxide film 2 are evaporated, and an activation layer 3 is formed. Here, the energy line is 193 nm in wavelength and 20 nm in pulse width.
s, energy density per pulseless 2MW/pulse
- Use one ArF excimer laser. Next, Figure 1 (c
), when aluminum is deposited by the vapor phase growth method, the aluminum wiring 5 is selectively formed on the activation layer 3. By a growth method, the aluminum wiring 5 is selectively formed at a substrate temperature of 250° C., a carrier hydrogen flow rate of 60 SCCM, and a vacuum chamber pressure of 2 Torr. The time required to form the wiring is the sum of the time to sweep the energy line 4 and the time to form the wiring thin film. The time to sweep the energy line 4 is sufficiently shorter than the method of directly drawing thick wiring using laser vapor phase epitaxy, and the selective deposition rate of the wiring thin film is approximately 500 OA/mi.
Since the method is as fast as n, the time required for wiring formation can be shortened compared to a method of directly drawing wiring using laser vapor phase epitaxy. Further, according to the wiring forming method of the present invention, the process can be shortened to two steps: patterning and film formation.

Note that even when a single energy line 4 is irradiated onto the silicon substrate 1, which is originally active for selective deposition of this wiring thin film,
It goes without saying that the silicon substrate 1 remains active in the deposition of thin films for wiring, and that selectivity is maintained. It goes without saying that it can also be simultaneously deposited on areas that are naturally active for the deposition of interconnect thin films, such as silicon, polysilicon, metals, etc., and that this can be used to provide advantages in device manufacturing processes.

In this example, dimethylaluminum hydride was used as the raw material gas for wiring, but triisobutylaluminum or the like may also be used. In addition, although aluminum is used as the wiring material, tungsten or the like which can be formed using WF6 etc. may also be used.Furthermore, the irradiated energy line has an intensity that can activate the irradiation area and is less than or equal to the desired wiring width. Light, within the range where the irradiation area can be narrowed down to
The substrate may be selected from atoms, molecules, radicals, ions, etc., and the substrate may be a compound integrated circuit or the like other than a silicon integrated circuit.

In this embodiment, a method of directly drawing wiring has been described, but it goes without saying that the present invention can also be practiced by a method of forming wiring by projection using a mask.

〔Effect of the invention〕

As described above, the present invention can reduce the number of operations and processes and form wiring with a high throughput, so it has the effect of reducing the manufacturing process and cost of wiring used in integrated circuits and the like.

[Brief explanation of drawings]

FIGS. 1(a) to 1(c) are sectional views showing the main steps of an embodiment of the present invention. 1... Silicon substrate, 2... Silicon oxide film, 3.
...Activation layer, 4... Energy line, 5... Aluminum wiring. (α)

Claims (1)

[Claims] The surface of the substrate is activated for the deposition by irradiating a line of energy onto the wiring area of a substrate which is inactive for the deposition of a thin film for wiring using a vapor deposition method, and then the wiring is deposited on the substrate by a vapor deposition method. 1. A method for forming wiring, characterized by depositing a thin film for use in wiring.