KR100186253B1 - Method of manufacturing silicon fea by locos - Google Patents

Abstract

An object of the present invention is to be able to form a uniform silicon substrate in a large area substrate by using a silicon FEA manufacturing method by LOCOS and to reduce the driving voltage by forming a gate hole less than a photomask.

After nitriding the nitride film on the silicon substrate and locally oxidizing the silicon substrate by LOCOS to form a thermal oxide film, the thermal oxide film is etched. Thereafter, the silicon substrate is thermally oxidized to form a gate oxide film, and a metal is deposited on the gate oxide film to form a gate electrode. A lift-off process is performed to expose the conical tip emitter.

Description

Silicon FEA manufacturing method by LOCOS

1a to 1f are cross-sectional views showing a silicon FEA manufacturing process by a conventional method,

2a to 2f are cross-sectional views showing a silicon FEA manufacturing process according to the present invention.

* Explanation of symbols for main parts of the drawings

21 silicon substrate 22 nitride film

23: thermal oxide film 24: gate oxide film

25 gate electrode 26 tip emitter

The present invention relates to a method for manufacturing a field-emission array (FEA) of a flat panel display, and more particularly, it is possible to form a uniform tip emitter on a large-area substrate as well as to reduce a driving hole by reducing a gate hole. It is by the method of manufacturing silicon FEA by LOCOS (Local Oxidation of Silicon).

In recent years, with the rapid development of ultra-high density semiconductor manufacturing technology and ultra-high vacuum technology, research into a new type of three-pole vacuum tube device having a micron size has been vigorous. It is paying attention to the development of a new flat panel display having only the advantages of CRT and LCD by applying such a device to a display.

FED (Field-Emission Display) is a kind of flat panel display, which consists of micro tip-shaped cathode, gate electrode for electric field emission, and anode coated with phosphor, and is generated by inducing electron emission from many micro tips. By colliding the electrons with the phosphor of the anode, a desired image display is performed by using light generated when the outermost electron of the phosphor is excited and transitioned.

A conventional silicon FEA manufacturing method will be described with reference to FIGS. 1A to 1F.

First, the silicon substrate 11 is oxidized and then photo-etched to form an oxide film 12 in the shape of a disc (FIG. 1a).

Next, the silicon substrate 11 is etched by RIE (reactive ion etching) using the oxide film 12 as a mask (FIG. 1B), and the silicon substrate 11 is sharply oxidized to form a thermal oxide film 13. (Figure 1c).

Thereafter, an oxide film is deposited to form the insulating film 14 (FIG. 1D), and a metal is deposited on the insulating film 14 to form the gate electrode 15 (FIG. 1E).

Finally, the tip emitter 16 is formed by etching the thermal oxide film 13 using the gate electrode as a mask (FIG. 1f).

However, in the conventional FEA manufacturing method, using the RIE method to form a conical tip emitter, the formation of a uniform and intact conical tip emitter due to the nonuniformity of plasma density when producing a large area panel is avoided. It was difficult and there was a problem in that it was not possible to manufacture a submicro tip due to the limitation of equipment when using an aligner.

In view of the above problems, the object of the present invention is not only to form a uniform conical tip emitter on a large area substrate, but also to produce fewer gate holes than the photomask due to the Bird's beak effect by LOCOS. It is to provide a silicon FEA manufacturing method that can reduce the driving contact pressure by forming a.

In order to achieve the object of the present invention, the present invention comprises the steps of forming a nitride film on a silicon substrate as a tip mask on a silicon substrate, locally thermally oxidizing by a silicon substrate LOCOS to form a thermal oxide film, and etching the thermal oxide film. Forming a gate oxide by sharpening and oxidizing a silicon substrate; depositing a metal on the gate oxide to form a gate electrode; and lifting-off to expose the tip of the conical tip emitter. It provides a process for producing a silicon FEA by LOCOS, characterized in that it comprises a step of performing a).

Hereinafter, a method for manufacturing silicon FEA by LOCOS of the present invention will be described in detail with reference to FIGS. 2A to 2F.

First, the nitride film 22 is deposited on the silicon substrate 21, and then patterned into a disk by LPCVD (low pressure chemical vapor deposition). (FIG. 2A).

Next, the silicon substrate 21 is locally thermally oxidized by LOCOS to form a thermal oxide film 23 (FIG. 2B), and the thermal oxide film 23 is etched as 7: 1 (BHF) (FIG. 2C). ).

Thereafter, the silicon substrate 21 is sharply oxidized to form a gate oxide film 24 (FIG. 2D), and a metal is deposited on the gate oxide film 24 using an E-beam evaporation to deposit a gate electrode 25. ) (Fig. 2e).

Finally, the tip emitter 26 is exposed by etching the gate oxide film 24 as 7: 1 (BHF) using the gate electrode 25 as a mask (FIG. 2f).

As described above, the present invention can form a uniform silicon substrate on a large-area substrate, can produce a silicon FEA having a good yield, and the size of the photomask in the form of a bird's beak by LOCOS. The driving voltage can be reduced by forming the gate hole reduced to about 70%.

In addition, by using the thermal oxide film as the gate oxide film, it is possible to eliminate a film quality defect of the deposited oxide film of the device manufactured by the conventional method.

Claims (1)

Forming a nitride film on the silicon substrate as a tip mask, locally thermally oxidizing the silicon substrate by LOCOS, etching the thermal oxide film, and sharpening the silicon substrate. Oxidizing to form a gate oxide film; depositing a metal on the gate oxide film to form a gate electrode; and performing a lift-off process to expose the tip of the conical tip emitter. Method for producing a silicon FEA by LOCOS characterized in that.