KR100454075B1 - Method of manufacturing bipolar transistor in semiconductor device - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a bipolar transistor of a semiconductor device, and provides a technology capable of improving the performance of a transistor by increasing the base width of the bipolar transistor by manufacturing a buried bipolar transistor. A method of manufacturing a bipolar transistor of a semiconductor device according to the present invention may include etching the first oxide film and the nitride film formed on a silicon substrate by a photoresist pattern, and then etching the silicon substrate to a predetermined depth; Removing the nitride layer and removing the first oxide layer only at a portion where a first epitaxial layer is to be formed; After forming a first epitaxial layer having a type opposite to the silicon substrate on the structure, the remaining first oxide layer is removed, and a second epitaxial layer having a type opposite to the first epitaxial layer is continuously formed. Forming a technical layer as a base; A second oxide film is formed on the structure, and then a predetermined portion is etched, a polysilicon layer is formed to form an emitter, and then the planarized shape is buried by chemical mechanical polishing (CMP) process until the second oxide film is exposed. Forming an emitter of; Removing the second oxide film, and then forming a first photoresist film on the structure to form a diffusion layer of the same type as the base epitaxial layer through ion implantation under the base electrode; Removing the first photoresist film and forming a second photoresist film to form a shallow diffusion layer of a collector-like type under the collector electrode through ion implantation; Removing the second photoresist film and forming an interlayer insulating oxide film; Contacting the interlayer insulating oxide layer to bury a metal material, and thereafter separating the interlayer contact hole buried through a chemical mechanical polishing (CMP) process; And forming a first metal wire on the structure to connect the lower conductive layer, and etching the first metal wire to form a pattern.

Description

Bipolar transistor manufacturing method of a semiconductor device {METHOD OF MANUFACTURING BIPOLAR TRANSISTOR IN SEMICONDUCTOR DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a bipolar transistor of a semiconductor device, and more particularly, to a method of manufacturing a bipolar transistor of a semiconductor device in which a base width of a bipolar transistor is increased by manufacturing a buried bipolar transistor.

In general, a PN junction formed by contacting a P-type semiconductor and an N-type semiconductor region in a semiconductor substrate has rectifying characteristics and is the most basic component of a semiconductor device. It is a bipolar transistor in which such a PN junction consists of two layers. Such bipolar transistors apply forward bias to one PN junction and reverse bias to the other PN junction to induce the movement of electrons and holes.

On the other hand, when manufacturing a bipolar transistor, in order to minimize the series resistance of the collector, the N-type impurity is introduced to penetrate the epitaxial layer and contact the high concentration N-type impurity buried layer existing between the epitaxial layer and the substrate. A sink process is used to diffuse.

In the conventional semiconductor device, as the design rule of the semiconductor device becomes smaller, there are many difficulties in increasing the driving current of the bipolar transistor with the gain of the bipolar transistor. In addition, to increase the gain of the bipolar transistor, the base width must be reduced. To this end, there have been many difficulties in growing a thin epitaxial layer.

Accordingly, the present invention has been made to solve the above problems, and an object of the present invention is to increase the base width of the bipolar transistor by manufacturing a buried bipolar transistor to improve the performance of the transistor bipolar transistor manufacturing method of a semiconductor device. To provide.

1 to 8 are cross-sectional views illustrating a method of manufacturing a bipolar transistor according to the present invention.

(Explanation of symbols for the main parts of the drawing)

1: silicon substrate 2: oxide film

3: nitride film 4: first epitaxial layer

5: second epitaxial layer 6: diffusion layer

7: emitter 8: first photosensitive film

9 Diffusion Layer 10 Second Photosensitive Film

11: thin diffusion layer 12: interlayer insulating oxide film

13 contact hole 14 first metal wiring

Bipolar transistor manufacturing method of a semiconductor device of the present invention for achieving the above object,

Etching the first oxide film and the nitride film formed on the silicon substrate by a photoresist pattern, and then etching the silicon substrate to a predetermined depth;

Removing the nitride layer and removing the first oxide layer only at a portion where a first epitaxial layer is to be formed;

After forming a first epitaxial layer having a type opposite to the silicon substrate on the structure, the remaining first oxide layer is removed, and a second epitaxial layer having a type opposite to the first epitaxial layer is continuously formed. Forming a technical layer as a base;

A second oxide film is formed on the structure, and then a predetermined portion is etched, a polysilicon layer is formed to form an emitter, and then the planarized shape is buried by chemical mechanical polishing (CMP) process until the second oxide film is exposed. Forming an emitter of;

Removing the second oxide film, and then forming a first photoresist film on the structure to form a diffusion layer of the same type as the base epitaxial layer through ion implantation under the base electrode;

Removing the first photoresist film and forming a second photoresist film to form a shallow diffusion layer of a collector-like type under the collector electrode through ion implantation;

Removing the second photoresist film and forming an interlayer insulating oxide film;

Contacting the interlayer insulating oxide layer to bury a metal material and then separating the interlayer contact hole buried through a chemical mechanical polishing (CMP) process; And

And forming a first metal wire on the structure to connect the lower conductive layer, and etching the first metal wire to form a pattern.

The first and second epitaxial layers having different types in the collector portion may be of the same type by ion implantation.

When the collector contact hole is etched, the etching margin of the contact hole is secured by a diffusion layer of the same type as the epitaxial layer.

By forming a diffusion layer of the same type as the base epitaxial layer in a portion where the contact hole of the base portion is formed, the contact epitaxial layer is connected to diffusion even when the base epitaxial layer is excessively etched to secure an etching margin of the contact hole. It is done.

The area of the base is controlled by the etching target during the silicon substrate etching.

Bipolar transistor manufacturing method of another semiconductor device of the present invention for achieving the above object,

Etching the first oxide film and the nitride film formed on the silicon substrate by a photoresist pattern, and then etching the silicon substrate to a predetermined depth;

Removing the nitride layer and removing the first oxide layer only at a portion where a first epitaxial layer is to be formed;

After forming the first epitaxial layer having the same type as the silicon substrate on the structure, the remaining first oxide layer is removed, and the second epitaxial layer having the opposite type as the first epitaxial layer is continuously formed. Forming a technical layer as a base;

A second oxide film is formed on the structure, and then a predetermined portion is etched, a polysilicon layer is formed to form an emitter, and then the planarized shape is buried by chemical mechanical polishing (CMP) process until the second oxide film is exposed. Forming an emitter of;

Removing the second oxide film, and then forming a first photoresist film on the structure to form a diffusion layer of the same type as the base epitaxial layer through ion implantation under the base electrode;

Removing the first photoresist film and forming a second photoresist film to form a shallow diffusion layer of a collector-like type under the collector electrode through ion implantation;

Removing the second photoresist film and forming an interlayer insulating oxide film;

Contacting the interlayer insulating oxide layer to bury a metal material and then separating the interlayer contact hole buried through a chemical mechanical polishing (CMP) process; And

And forming a first metal wire on the structure to connect the lower conductive layer, and etching the first metal wire to form a pattern.

(Example)

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

1 to 8 are cross-sectional views illustrating a method of manufacturing a bipolar transistor according to the present invention.

First, as shown in FIG. 1, the oxide film 2 and the nitride film 3 are deposited on the silicon substrate 1, and then a photosensitive film (not shown) is applied to form a pattern. Then, the nitride film 3 and the oxide film 2 are etched completely so that the silicon substrate 1 is exposed by the photosensitive film pattern.

Next, as shown in FIG. 2, after the nitride film 3 is removed, an epitaxial layer is formed on the oxide film 2 for blocking growth of an epitaxial layer (4 in FIG. 3). Remove only part.

Next, as shown in FIG. 3, the epitaxial layer 4 having one type for the collector of the bipolar transistor is grown on the silicon substrate 1, and then the remaining oxide film 2 is removed. do. Subsequently, a thin epitaxial layer 5 of a type opposite to the epitaxial layer 4 is successively formed on the structure as the base of the bipolar transistor.

Next, an oxide film 6 is grown on the structure, and then a desired portion is etched. A polysilicon layer 7 is then formed over the structure to form an emitter.

4, the polysilicon layer 7 is then planarized by a chemical mechanical polishing (CMP) process until the oxide film 6 is exposed. Thus, the polysilicon layer 7 forms an emitter 7 of buried form.

Then, as shown in FIG. 5, the oxide film 6 is removed to complete the desired bipolar transistor.

Next, as shown in FIG. 6, a photosensitive film 8 is deposited on the structure to form a diffusion layer 9 of the same type as the base epitaxial layer 5 under the base electrode through ion implantation. .

Next, as shown in FIG. 7, the photosensitive film 8 is removed, the photosensitive film 10 is applied again, and a shallow diffusion layer 11 of a collector-like type is formed under the collector electrode through ion implantation. do. At this time, epitaxial layers 4 and 5 having different types in the collector portion (A region) are of the same type by ion implantation.

Then, after removing the photosensitive film 10, an interlayer insulating oxide film 12 is deposited on the structure. Next, a contact hole is formed in a desired portion using a contact hole mask, and then a metal material is embedded. Then, the buried interlayer contact hole 13 is separated through a chemical mechanical polishing (CMP) process.

Then, the first metal wiring 14 is deposited to be connected to the lower conductive layer (Base, Emitter, Collector), and the first metal wiring 14 is etched using a first metal wiring mask to form a pattern. To complete the bipolar transistor.

As described in detail above, according to the method of manufacturing a bipolar transistor of a semiconductor device according to the present invention, by manufacturing a buried bipolar transistor, it is possible to increase the base width of the bipolar transistor to improve the performance of the transistor. In addition, the process can be reduced and the compatibility with the CMOS process can reduce the cost.

In addition, this invention can be implemented in various changes within the range which does not deviate from the summary.

Claims (10)

Etching the first oxide film and the nitride film formed on the silicon substrate by a photoresist pattern, and then etching the silicon substrate to a predetermined depth; Removing the nitride layer and removing the first oxide layer only at a portion where a first epitaxial layer is to be formed; After forming a first epitaxial layer having a type opposite to the silicon substrate on the structure, the remaining first oxide layer is removed, and a second epitaxial layer having a type opposite to the first epitaxial layer is continuously formed. Forming a technical layer as a base; A second oxide film is formed on the structure, and then a predetermined portion is etched, a polysilicon layer is formed to form an emitter, and then the planarized shape is buried by chemical mechanical polishing (CMP) process until the second oxide film is exposed. Forming an emitter of; Removing the second oxide film, and then forming a first photoresist film on the structure to form a diffusion layer of the same type as the base epitaxial layer through ion implantation under the base electrode; Removing the first photoresist film and forming a second photoresist film to form a shallow diffusion layer of a collector-like type under the collector electrode through ion implantation; Removing the second photoresist film and forming an interlayer insulating oxide film; Contacting the interlayer insulating oxide layer to bury a metal material and then separating the interlayer contact hole buried through a chemical mechanical polishing (CMP) process; And Forming a first metal wire on the structure and connecting the lower conductive layer to the lower conductive layer, and etching the first metal wire to form a pattern. The method of claim 1, And a first and second epitaxial layers having different types in the collector portion are of the same type by ion implantation. The method of claim 2, The method of manufacturing a bipolar transistor of a semiconductor device, characterized in that to secure the etching margin of the contact hole by the diffusion layer of the same type as the epitaxial layer during the collector contact hole etching. The method of claim 1, By forming a diffusion layer of the same type as the base epitaxial layer in a portion where the contact hole of the base portion is formed, the contact epitaxial layer is connected to diffusion even when the base epitaxial layer is excessively etched to secure an etching margin of the contact hole. A bipolar transistor manufacturing method of a semiconductor device. The method of claim 1, The method of manufacturing a bipolar transistor of a semiconductor device, characterized in that for adjusting the width of the base by the etching target during the silicon substrate etching. Etching the first oxide film and the nitride film formed on the silicon substrate by a photoresist pattern, and then etching the silicon substrate to a predetermined depth; Removing the nitride layer and removing the first oxide layer only at a portion where a first epitaxial layer is to be formed; After forming the first epitaxial layer having the same type as the silicon substrate on the structure, the remaining first oxide layer is removed, and the second epitaxial layer having the opposite type as the first epitaxial layer is continuously formed. Forming a technical layer as a base; A second oxide film is formed on the structure, and then a predetermined portion is etched, a polysilicon layer is formed to form an emitter, and then the planarized shape is buried by chemical mechanical polishing (CMP) process until the second oxide film is exposed. Forming an emitter of; Removing the second oxide film, and then forming a first photoresist film on the structure to form a diffusion layer of the same type as the base epitaxial layer through ion implantation under the base electrode; Removing the first photoresist film and forming a second photoresist film to form a shallow diffusion layer of a collector-like type under the collector electrode through ion implantation; Removing the second photoresist film and forming an interlayer insulating oxide film; Contacting the interlayer insulating oxide layer to bury a metal material and then separating the interlayer contact hole buried through a chemical mechanical polishing (CMP) process; And Forming a first metal wire on the structure and connecting the lower conductive layer to the lower conductive layer, and etching the first metal wire to form a pattern. The method of claim 6, And a first and second epitaxial layers having different types in the collector portion are of the same type by ion implantation. The method of claim 7, wherein The method of manufacturing a bipolar transistor of a semiconductor device, characterized in that to secure the etching margin of the contact hole by the diffusion layer of the same type as the epitaxial layer during the collector contact hole etching. The method of claim 6, By forming a diffusion layer of the same type as the base epitaxial layer in a portion where the contact hole of the base portion is formed, it is connected to the diffusion even if the base epitaxial layer is excessively etched during the contact hole etching to secure the etching margin of the contact hole A bipolar transistor manufacturing method of a semiconductor device. The method of claim 6, The method of manufacturing a bipolar transistor of a semiconductor device, characterized in that for adjusting the width of the base by the etching target during the silicon substrate etching.