JPH10261360A - Manufacture of vacuum micro element and vacuum micro element through the manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vacuum micro element using diamond on its emitter and a manufacturing method of the micro element. SOLUTION: A vacuum micro element is manufactured by the processes of growing diamond cores 101 on a silicon board 102 as the body emitter, etching the board 102 to a desired depth with the cores 101 used as the mask, forming a gate insulating oxide film layer 103, a gate electrode Mo layer 104 successively and applying a resist, etching the resist until the cores 101 are exposed outside, and etching the electrode layer 104 and the insulating layer 103 with the resist used as the mask to remove the resist.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a vacuum micro device having a field emission cold cathode and its structure.

[0002]

2. Description of the Related Art In recent years, field-emission vacuum microdevices have been active due to the possibility of high-speed response, the possibility of improving radiation resistance and high temperature resistance, and the possibility of high-definition, self-luminous display. R & D is ongoing. A material having a small electron affinity is used as an emitter material of the vacuum micro device. For example, in recent years, it has been found that the affinity of diamond is close to 0 (reference: J. Van).
J. et al. VacSci. Technol. B, 10, 4,
(1992)), a number of methods for forming a vacuum micro device using diamond as an emitter material have been proposed.

[0003] For example, V. V. Proposal by Zhiron et al. (Literature: J. Vac. Sci. Technology. B13)
In (2), Mar / Apr 1995), a pillar structure having a height of 100 μm and a diameter of several μm is formed by processing Si serving as a base of the emitter, and then a Si-Au alloy is formed several μm ahead of the structure. Then, sharpen the tip using etching or oxidation technology. The sharpened Si emitter is coated with diamond. However, the diamond-coated emitter formed by this method lacks stability and reliability because diamond is not uniformly formed on individual Si chips.

[0004]

SUMMARY OF THE INVENTION In the present invention, in consideration of the current state of the prior art vacuum micro-elements in which diamond is used as the emitter material as described above, an emitter having diamond only at each end of the base emitter material is formed. And
We propose a new vacuum micro-element that can fully utilize the original characteristics of diamond and its structure.

[0005]

According to the gist of the present invention, a diamond nucleus is grown on a material serving as a base material of an emitter, and the base material emitter is processed using the diamond nucleus as a mask.
The object is to form an emitter having diamond only at the tip of the matrix emitter.

[0006]

According to the present invention, it is possible to realize a vacuum micro device capable of obtaining stable characteristics without the diamond coated on the emitter being present uniformly as in the prior art.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 to 9 are process sectional views showing a method for manufacturing a vacuum micro device according to an embodiment of the present invention.

First, as shown in FIG. 1, a diamond nucleus 101 is formed on a first substrate serving as a base emitter, for example, a Si substrate 102. The diamond nuclei used in this embodiment are generated at an early stage of diamond growth.
The probability that diamonds will form on the substrate is 10 ⁸ / cm
1μm in example of 1 cm ² area region because of its ²
Will occur at intervals. In this embodiment, a hot filament method was used to form diamond nuclei. The diamond nucleus has a hydrogen flow rate of 100 sccm and an acetone flow rate of 0.5 sc
cm of mixed gas was introduced into the reaction chamber, and the reaction pressure was 10
0 Torr and a substrate temperature of 800 ° C. Nuclear growth time is 1
It was time and the grown nuclei were on average about 1 μm in diameter. Next, as shown in FIG. 2, using the diamond nuclei 101 as a mask, the Si substrate, which is the base emitter, is etched. The etching is performed to a predetermined depth by, for example, a reactive ion etching (RIE) method. In the present invention, etching was performed to a depth of 500 nm. This step completes the emitter shape. As shown in FIG. 3, a material to be the gate insulating layer 103, for example, an oxide film is formed on the entire surface of the substrate by sputtering so as to cover the emitter shape. Here, it was formed with a thickness of 400 nm. Next, a gate electrode 104 is formed on the oxide film 103 as shown in FIG. In this example, molybdenum (Mo) was formed to a thickness of 500 nm by a sputtering method. Further, a resist 105 is applied to the entire surface of the substrate by a spinner. In the present embodiment, coating is performed with a film thickness of about 1 μm,
Thereafter, a heat treatment was performed at 150 ° C. for 30 minutes.

Next, as shown in FIG. 6, the resist 105 is etched by an etch bag method until a part of Mo serving as the gate electrode 104 on the diamond nucleus 101 is exposed. Etchback can be performed by a chemical dry etching method (CDE method) or the like.

Here, for example, the etch back conditions include a CF4 gas flow rate of 140 sccm and an O2 gas of 90 sccm.
And a pressure of 0.5 Torr and a microwave power of 600 W.

Further, as shown in FIG. 7, the resist 105a etched back in FIG.
04 is etched. The CDE method used for etching the resist was used for the etching. The etching conditions were the same as for the resist. In this CDE method, the gate electrode 104
Since the selectivity between the material Mo and the oxide film serving as the gate insulating layer 103 can be made large, it is easy to stop the etching when the oxide film is exposed. Then, FIG.
As shown in FIG. 7, the oxide film 103 was etched by wet etching using a chemical, and a part of the diamond nucleus 101 was exposed. The chemical was an ammonium fluoride solution, and the diamond nucleus 101 was exposed by etching for 5 minutes, and then additional etching was performed for 30 seconds. Finally, the resist 105a is removed as shown in FIG. As for the removing method, the stripping solution (Hakuri-10 manufactured by Tokyo Ohka) was heated to 80 ° C., and the substrate was immersed for 10 minutes to remove. After the removal, the substrate is washed with water and finally dried to complete the vacuum micro device according to the embodiment of the present invention. In this embodiment, the diamond nuclei 101 need not be arranged in an array in which the individual nuclei 101 are evenly spaced. Basically, it functions as a micro element if it exists within a predetermined area with a predetermined probability. However, if it is necessary to arrange them in an array for higher accuracy, it is possible to irradiate a beam to a predetermined location on the Si substrate 102 with a focused ion beam or the like and grow the nucleus 109 there. is there. According to the present embodiment, it is possible to form an emitter having diamond only at the tip of the base emitter, and it is possible to obtain a vacuum micro device having stable characteristics.

The present invention is not limited to the above embodiment, but can be implemented with various modifications without departing from the spirit of the present invention. Next, an embodiment of the flat panel display using the vacuum micro element according to the above embodiment will be described. As shown in FIG. 10, a parallel plate type image display device according to this embodiment has a Si substrate 102 (hereinafter, referred to as a vacuum micro device portion 100) on which a large number of vacuum micro device emitters are formed.
) And a glass face plate 201 in which a phosphor layer 203 and a transparent electrode (anode electrode) layer 202 made of ITO are sequentially formed, are arranged at a predetermined interval, and they constitute a vacuum housing. Have been. That is, the vacuum micro element unit 100 is used as a part of a vacuum housing.

Although the diamond nucleus is used as an emitter in the embodiment of the present invention, it can be used only as a mask. That is, this is a very effective means for sharpening the emitter. For example, in the above embodiment, after the Si substrate 102 is etched using the diamond nucleus 101 as a mask, thermal oxidation is formed. In this process, the Si substrate forms a very sharpened emitter. Finally, by removing the oxide film, the diamond nuclei are also removed (lift-off), and the very sharpened S
The i-emitter is exposed. Using this method, sharpened S can be achieved without the processes of exposure, development, and patterning.
An i-emitter can be realized.

[0014]

As described above, the use of the present invention improves the stability and reproducibility of the diamond emitter shape.
Further, it is possible to provide a vacuum micro device capable of significantly reducing the production cost.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a manufacturing process of a vacuum micro device according to one embodiment of the present invention.

FIG. 2 is a sectional view showing a manufacturing process of the vacuum micro device according to one embodiment of the present invention.

FIG. 3 is a sectional view showing a manufacturing process of the vacuum micro device according to one embodiment of the present invention.

FIG. 4 is a sectional view showing a manufacturing process of the vacuum micro device according to one embodiment of the present invention.

FIG. 5 is a sectional view showing a manufacturing process of the vacuum micro device according to one embodiment of the present invention.

FIG. 6 is a sectional view showing a manufacturing process of the vacuum micro device according to one embodiment of the present invention.

FIG. 7 is a sectional view showing a manufacturing process of the vacuum micro device according to one embodiment of the present invention.

FIG. 8 is a sectional view showing a manufacturing process of the vacuum micro device according to one embodiment of the present invention.

FIG. 9 is a sectional view showing a manufacturing process of the vacuum micro device according to one embodiment of the present invention.

FIG. 10 is a sectional view showing a flat panel display according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 100 ... Vacuum micro element part 101 ... Diamond nucleus 102 ... Si substrate 103 ... Gate insulating oxide film layer 104 ... Gate electrode Mo layer 105 ... Resist 201 ... Face plate 202 ... Transparent electrode (anode electrode) 203 ... Phosphor layer

Claims (2)

[Claims] A step of forming a diamond nucleus on a substrate; a step of forming an emitter by etching the substrate using the nucleus as a mask; a step of sequentially stacking an insulating film and a gate electrode on the emitter; Opening a part of the gate electrode and the insulating film to expose the diamond nucleus. 2. A vacuum micro device comprising a diamond at only a tip of an emitter manufactured by the method according to claim 1.