KR100340854B1 - Method for fabricating contact hole for forming capacitor of semiconductor device - Google Patents

Abstract

PURPOSE: A method for fabricating a contact hole for forming a capacitor of a semiconductor device is provided to increase a design margin by the width of a sidewall spacer by forming a sidewall spacer made of polysilicon on the sidewall of a portion where the contact hole for forming the capacitor is to be formed while using a process for forming the contact hole for fabricating a bitline and a process for forming the bitline. CONSTITUTION: The first interlayer dielectric(3) is deposited on a semiconductor substrate(1) having a filed oxide layer(2) and a MOS(Metal Oxide Semiconductor) transistor. A contact hole for forming the bitline and a temporary contact hole for forming the capacitor are formed. Polysilicon for the bitline is deposited and an ion implantation process is performed. A silicide layer and a nitride layer are sequentially deposited. The first photoresist pattern for forming the bitline is formed. The nitride layer, the silicide layer and the polysilicon for the bitline are etched to form the bitline by using the first photoresist pattern as an etch barrier while the sidewall spacer made of polysilicon is formed in a capacitor formation region. Residual photoresist is removed and the second interlayer dielectric(9) is formed. The second photoresist pattern for defining the contact hole for the capacitor is formed. The second interlayer dielectric is etched to form the contact hole for forming the capacitor by using the second photoresist pattern as an etch barrier. Residual photoresist is eliminated.

Description

Contact hole formation method for capacitor formation of semiconductor device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a method of manufacturing a semiconductor device, and more particularly to a method of forming a contact hole for forming a capacitor more easily using a contact hole forming process for forming a bit line and a process for manufacturing a bit line. will be.

As semiconductor devices are highly integrated, the size of the cell region is reduced, and the size of the contact hole is also reduced. As a method of forming a contact hole for forming a charge storage electrode of a conventional capacitor, since the interlayer insulating layer to be etched when forming the contact hole is thick, a contact hole can be formed with an accurate difference between the upper and lower portions of the contact hole after etching. Had the problem.

Accordingly, the present invention devised to solve the above-described problems is to provide a process for forming a single contact for forming a bit line and a portion for forming a contact hole for forming a capacitor using a process for manufacturing a bit line. An object of the present invention is to provide a method of forming a contact hole for increasing a design margin by the width of the sidewall spacer and forming a capacitor more easily by forming a sidewall spacer made of polysilicon on the sidewall.

The method of forming a contact hole for forming a capacitor of the present invention comprises the steps of depositing a first interlayer insulating film on a structure in which a field oxide film and a MOS transistor are formed on a semiconductor substrate, and a temporary hole for forming a contact hole and a capacitor for forming a bit line. Forming a contact hole, depositing polysilicon for a bit line and performing ion implantation, depositing a silicide layer and a nitride layer in order, forming a first photoresist pattern for forming a bit line, and forming the first photo Forming a bit line by etching the nitride film, the silicide film and the polysilicon for the bit line using a resist pattern as an etching barrier, and simultaneously forming a sidewall spacer made of polysilicon in a region where the capacitor is to be formed; Removing the photoresist and forming a second interlayer dielectric film and caching After forming a second photoresist pattern defining a contact hole for forming a capacitor, the second interlayer insulating layer is etched using the second photoresist pattern as an etch barrier to form a contact hole for forming a capacitor and remaining. And removing the photoresist.

An embodiment of a method for forming a contact hole for forming a capacitor of the present invention will now be described in detail with reference to the accompanying drawings. First, as shown in FIG. 1A, a first interlayer insulating film 3 is deposited on a structure in which a field oxide film 2 and a MOS transistor are formed on a semiconductor substrate 1. Next, as shown in FIG. 1B, a contact hole for forming a bit line and a temporary contact hole for forming a capacitor are formed. Next, as shown in FIG. 1C, the bit line polysilicon 4 is deposited and ion implanted, and then the silicide film 5 and the nitride film 6 are sequentially deposited. Next, as shown in FIG. 1D, a first photoresist pattern 7 for forming a bit line is formed, and the nitride film 6 and the silicide layer are formed using the first photoresist pattern 7 as an etch barrier. (5) and the bit line polysilicon 4 are etched to form bit lines, and at the same time, sidewall spacers 8 made of polysilicon are formed in the region where the capacitor is to be formed. Next, as shown in FIG. 1E, the residual photoresist is removed and the second interlayer insulating film 9 is formed. After forming a second photoresist pattern defining a contact hole for forming a capacitor, the second interlayer insulating layer 9 is etched using the second photoresist pattern as an etch barrier to form a contact hole for forming a capacitor. Form and remove residual photoresist.

In manufacturing a semiconductor device, according to the present invention as described above, by forming a sidewall spacer made of polysilicon, a contact hole for increasing the design margin as much as the width of the sidewall spacer and forming a capacitor more easily is provided. Can be formed.

1A to 1E are process diagrams according to a contact hole forming method for forming a capacitor of the present invention.

※ Explanation of code about main part of drawing ※

1: semiconductor substrate 2: field oxide film

3: first interlayer insulating film 4: polysilicon for bit line

5: silicide film 6: nitride film

7: first photoresist pattern

8 side wall spacer 9 second interlayer insulating film

Claims (1)

In the method of forming a contact hole for forming a capacitor, Depositing a first interlayer insulating film on a structure in which a field oxide film and a MOS transistor are formed on a semiconductor substrate; Forming a contact hole for forming a bit line and a temporary contact hole for forming a capacitor; Depositing polysilicon for bit lines and ion implantation, and then depositing a silicide film and a nitride film in sequence; A bit line is formed by forming a first photoresist pattern for forming a bit line and etching the nitride film, the silicide layer, and the polysilicon for the bit line using the first photoresist pattern as an etch barrier. Forming sidewall spacers made of polysilicon in the region to be formed; Removing residual photoresist and forming a second interlayer dielectric film; After forming a second photoresist pattern defining a contact hole for forming a capacitor, the second interlayer insulating layer is etched using the second photoresist pattern as an etch barrier to form a contact hole for forming a capacitor, and to form a residual photo. A method of forming a contact hole for forming a capacitor comprising the step of removing the resist.