JPH03257849A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To perform an application of an SOG film with a good uniformity by applying the SOG film from both the directions of a normal and reverse rotation. CONSTITUTION:An irregular surface 3 of an insulating film 2 on a semiconductor substrate 1 is coated with an SOG film 4, rotating the substrate 1. Then, the surface 3 is coated with an SOG film 41, rotating the substrate 1 in the reverse direction. Thereafter, the heating of the substrate is performed. Making the SOG film 4 and the SOG film 41 cure, a film 42 is obtained, and an upper layer film 5 is deposited thereon. Thereby, the characteristic of coating a refined pattern with the SOG film, which is a difficult thing to perform by usual methods, is improved. Consequently, a remarkable effect can be shown in the manufacture of refined semiconductor devices, particularly the ones using multilayer metallic wirings.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of manufacturing a semiconductor device having fine multilayer metal wiring.

Conventional technology Semiconductor devices are evolving endlessly towards higher integration.

Particularly recently, highly integrated semiconductor devices having a multilayer metal wiring structure have been increasing. Generally, in metal wiring using an aluminum alloy, the film thickness of the aluminum alloy is formed to be thick in order to improve reliability, such as disconnection of the wiring. Therefore, the steps tend to be thick, and planarization technology is particularly important when forming multilayer metal wiring.Generally, planarization technology is used when forming multilayer metal wiring for fine semiconductor devices. Among these, the most popular technology is spin-on-glass (hereinafter abbreviated as SOG).This method is
SOG applied to uneven parts of semiconductor substrate surface during multilayer metal wiring process
A film (a glass film in a liquid phase) is spin-coated and then heated and cured to reduce irregularities on the surface of a semiconductor substrate.

FIGS. 2(a) and 2(b) are cross-sectional views in the order of steps of forming an SOG film using a conventional method. As shown in FIG. 2(a), an SOG film 4 is formed on the insulating film 22 having the stepped portion 3, and then an upper layer film 5 is provided as shown in FIG. 2(b). .

Problems to be Solved by the Invention However, although this SOG method is simple, in recent ultrafine processing, the d-cloth characteristics of the SOG film 4 tend to be pattern dependent, resulting in a decrease in yield at the stage of semiconductor device fabrication. was a contributing factor. - In the boat fishing SOG method, the substrate is rotated in one direction and the SOG film is dropped from the center arrow part, or the substrate is dropped and then rotated in one direction, but this method inevitably affects the state of the SOG film coating. is easy to appear. Although some improvement can be achieved by optimizing the viscosity of the SOG film to be dropped, it is actually difficult to select the appropriate viscosity depending on the product.

Means for Solving the Problems In the present invention, in order to solve the above-mentioned problems in the SOG film coating process, the direction of rotation of the substrate is reversed so that the coating characteristics of the SOG film are not directional.

Function: With this configuration, by applying SOG@ from two directions, forward and reverse, the SOG film can be applied more uniformly than in the conventional method.

Embodiment An embodiment of the present invention will be described with reference to the drawings. FIGS. 1A to 1C are cross-sectional views showing steps in the method for manufacturing a semiconductor device of the present invention. First, the SOG film 4 is spin-coated on the uneven surface 3 of the insulating film 2 on the semiconductor substrate 1 (first
Figure (a)). Next, the semiconductor substrate 1 is rotated in the opposite direction and the SO
A G film 41 is spin-coated (FIG. 1(b)). Thereafter, heating is performed to harden the SOG film 4 and the SOG film 41, and the upper layer film 42 is deposited (FIG. 1(C)).

Effects of the Invention By using the present invention, the SOG film coating characteristics in fine patterns, which were difficult to achieve using conventional methods, have been improved, and great effects can be exhibited in the manufacture of fine semiconductor devices, especially semiconductor devices that use multilayer metal wiring. It is something.

[Brief explanation of drawings]

FIG. 1 is a step-by-step sectional view of a method for manufacturing a semiconductor device according to an embodiment of the present invention, and FIG. 2 is a step-by-step sectional view of a conventional method for manufacturing a semiconductor device. l... Semiconductor substrate, 2... Uneven surface, 3
...Insulating film, 4...SOG film, 41.
...SOG film, 42...SOG film, 5.
...upper layer membrane.

Claims (2)

[Claims] (1) Dropping a liquid phase substance on the uneven surface of the semiconductor substrate without rotating it in a certain direction, applying the liquid phase substance to the uneven surface of the semiconductor substrate, and rotating the uneven surface of the semiconductor substrate in the opposite direction. A method for manufacturing a semiconductor device, comprising the steps of: dropping the liquid phase substance while rotating the semiconductor substrate; and applying the liquid phase substance again to the uneven surface of the semiconductor substrate. 2. The method of manufacturing a semiconductor device according to claim 1, further comprising: (2) reversing the rotational direction of the semiconductor substrate two or more times.