KR19980055732A - Capacitor Manufacturing Method of Semiconductor Device - Google Patents

Abstract

The present invention relates to a method of manufacturing a capacitor of a semiconductor device, and a contact hole is formed on one side of each T-shaped cell on a silicon substrate on which a bit line is formed through a predetermined process, a capacitor is formed, and then an insulating film is formed. Forming a capacitor after forming a contact hole on the other side has the effect of increasing the capacitance of the capacitor and reducing the step.

Description

Capacitor Manufacturing Method of Semiconductor Device

The present invention relates to a method of manufacturing a capacitor, and more particularly, to a method of manufacturing a capacitor of a semiconductor device capable of increasing the capacitance of the capacitor and alleviating the step.

In general, as the integration of semiconductor devices proceeds, the size of a unit cell becomes smaller, and the capacitance required for device operation tends to increase slightly.

The capacitance of the capacitor can be represented by the following formula.

[expression]

Q: Capacitanceε ₀ : Dielectric constant (air)

ε ₁ : Dielectric constant A of dielectric material 1: capacitor area

d: film thickness

Referring to the capacitance of the capacitor as shown in the above [formula] is as follows.

First, the use of materials having a high dielectric constant, which has the disadvantage of having a large leakage current (leakage current) and difficult to control the production of the material. In general, the dielectric material used in the semiconductor device uses an ONO structure formed of a silicon oxide film (SiO ₂ ) and a silicon nitride film (Si ₃ N ₄ ).

Second, to reduce the thickness of the dielectric material. However, in the ONO structure currently used, Tox (oxide conversion thickness) has a large leakage current at about 40 mA or less, and is easily broken down, which makes it difficult to maintain stable capacitance.

Finally, there is a way to increase the surface area of the capacitor.

FIG. 1 shows a plan view for forming a charge storage electrode in each cell 1A, 1B and 1C having a T shape. First contact holes 2A, 2B, and 2C are formed at one side of each of the T-shaped cells 1A, 1B, and 1C, and second contact holes 3A, 3B, and 3C are formed at the other side thereof. The first and second contact holes 2A, 2B, 2C and 3A, 3B, 3C are formed at the same time. The first charge storage electrodes 4A, 4B, and 4C are formed on the first contact holes 2A, 2B, and 2C, and the first charge storage electrodes are formed on the second contact holes 3A, 3B, and 3C. 5A, 5B and 5C) are formed. The first and second charge storage electrodes 4A, 4B, 4C and 5A, 5B, 5C are formed at the same time.

Since the charge storage electrodes 4A, 4B, 4C, and 5A, 5B, and 5C formed as described above should be formed so as not to contact each other in size, the area is limited and a small margin is generated as shown by arrow A. do.

Therefore, according to the present invention, a contact hole is formed on one side of each cell on the silicon substrate on which the bit line is formed through a predetermined process, a capacitor is formed correspondingly, an insulating film is formed, and a contact hole is formed on the other side, and then a capacitor is formed. It is an object of the present invention to provide a method for manufacturing a capacitor of a semiconductor device which can be formed so that each capacitor overlaps each other.

A capacitor manufacturing method according to the present invention for realizing the above object comprises the steps of forming a first contact hole on one side of each cell on a silicon substrate on which a bit line is formed through a predetermined process, and corresponding to each of the first contact holes. Forming first insulating films so that the first capacitors do not come into contact with each other, and then forming an insulating layer, forming a second contact hole on the other side of each cell, and preventing each other from contacting each other in correspondence with the second contact holes. Comprising a step of forming a second capacitor and the size of the first capacitor and the second capacitor is formed the same, each of the second capacitor and the first capacitor is formed to overlap each other.

1 is a cross-sectional view of a device for explaining a charge storage electrode method of a conventional semiconductor device.

2 is a cross-sectional view of a device for explaining a capacitor manufacturing method of a semiconductor device according to the present invention.

Explanation of symbols on the main parts of the drawings

1A, 1B, 1C and 11A, 11B, 11C: Cell

2A, 2B, 2C and 12A, 12B, 12C: first contact hole

2nd contact hole: 3A, 3B, 3C and 13A, 13B, 13C

4A, 4B and 4C: first charge storage electrode

5A, 5B and 5C: second charge storage electrode

14A, 14B and 14C: first capacitor

15A, 15B and 15C: Second Capacitor

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

2 shows a plan view for forming a charge storage electrode in each of the cells 11A, 11B and 11C having a T shape.

First contact holes 12A, 12B, and 12C are formed at one side of each of the T-shaped cells 11A, 11B, and 11C on the silicon substrate on which the bit line is formed through a predetermined process, and then the first contact hole 12A, Corresponding to 12B and 12C, first capacitors 14A, 14B and 14C are formed.

Each of the first capacitors 14A, 14B and 14C is formed so as not to touch each other. Next, second contact holes 13A, 13B, and 13C are formed on the other side, and second capacitors 15A, 15B, and 15C are formed corresponding to the second contact holes 13A, 13B, and 13C. Each of the second capacitors 15A, 15B, and 15C is formed so as not to touch each other, and overlapped or not overlapped with the first capacitors 14A, 14B, and 14C.

The first capacitors 14A, 14B and 14C and the second capacitors 15A, 15B and 15C have the same size and are electrically separated by an insulating film.

In the present embodiment, the T-shaped cell has been described, but is not limited thereto. That is, of course, the present embodiment can be applied to a Z-shaped cell and of course any other cell.

As described above, according to the present invention, a contact hole is formed on one side of each T-shaped cell on the silicon substrate on which the bit line is formed through a predetermined process, a capacitor is formed corresponding thereto, and an insulating film is formed on the other side. After the formation of the capacitor, the capacitor is formed, thereby increasing the capacitance of the capacitor and reducing the step.

Claims (3)

In the method of manufacturing a capacitor of a semiconductor device, Forming a first contact hole on one side of each cell on the silicon substrate on which the bit line is formed through a predetermined process; Forming an insulating film after forming a first capacitor so as not to contact each other corresponding to each of the first contact holes; Forming a second contact hole on the other side of each cell, And forming a second capacitor so as not to be in contact with each other in correspondence with each of the second contact holes. The method of claim 1, The method of claim 1, wherein the first capacitor and the second capacitor have the same size. The method of claim 1, And each of the second capacitor and the first capacitor is formed to overlap each other.