JPS6280938A - Manufacture of titanium compound field emitter - Google Patents

Abstract

PURPOSE:To improve stability, by applying a strong electric field under ultra- high vacuum, after subjecting the surface of a carbon titanium nitride mono crystal emitter to treatment with a gas including H2S or S. CONSTITUTION:After the surface of a TiCN emitter is subject to treatment at 900-1,400 deg.C, with a gas including H2S or S, or treated through the above- mentioned treatment and a treatment with O2 gas and/or C2H4 or other hydro- carbon gases in parallel, a strong electric field of 10<7>V/cm or more is further applied to the emitter under ultra-high vacuum. After the H2S treatment, the emitter is further heated to 900-1,400 deg.C in O2, where the heating time is chosen to be 5L or more. It is also possible to perform the H2S gas treatment after carrying out the O2 treatment in the reverse way, or they can be performed simultaneously as well with adjustments of introduced gas amounts to: 5: or more for O2 and 2L or more for H2S. These treatments allow simple manufacture of a field emitter presenting excellent stability.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing a field emitter exhibiting highly stable electron emission characteristics.

The radiation current from the field emitter has a large brightness,
Since the energy width of emitted electrons is small and it has excellent properties such as being close to a point light source, it is possible to realize new functional electron microscopes such as low-acceleration scanning electron microscopes, analytical electron microscopes, and electron beam holography microscopes. It is indispensable for high-resolution, and is also indispensable in fields such as nanometer lithography.

Prior Art Conventionally, W has been put into practical use as a field emitter. However, there are problems with current stability, which precludes wide application.

The present inventors previously developed a field emitter made of a transition metal compound with an emitter axis orientation of <110
>By selecting the direction, we succeeded in making the direction of the emitted electron beam the emitter axis direction, which had not been achieved previously. (Patent Application No. 199605, 1982). Furthermore, by treating the surface of the titanium carbide single crystal chip with oxygen gas (Japanese Patent Application No. 59-275220) and with hydrocarbon gas such as C2H4 (Japanese Patent Application No. 59-275221), highly stable electron emissivity can be achieved. We were able to develop a field emitter that exhibits the characteristics.

OBJECT OF THE INVENTION The object of the invention is to prepare titanium carbonitride (Ti CxNy, 0.
5≦x + y≦1) single crystal emitter (hereinafter T1CN
The purpose of the present invention is to develop a surface treatment method for field emitters (abbreviated as "field emitters"), and to provide a method for manufacturing field emitters that exhibit even better stability.

Structure of the Invention In order to achieve the above object, the present inventors continued their research, and as a result, the surface of the T1CN emitter was made of glass glass containing H2S or S (for example, 5F) (hereinafter abbreviated as H2S).90
After treatment at 0-1400°C, or a combination of this treatment with 02 gas and/or C2H4 or other hydrocarbon gas (e.g. C2H6) (hereinafter abbreviated as C2H4), further ultra-high vacuum It has been found that when a strong electric field of 107 ■/■ or more is applied under the conditions, the emission pattern changes and a field emitter exhibiting stable characteristics can be obtained. The present invention was completed based on this knowledge.

The gist of the present invention is 1) The T1CN emitter surface is
A method for producing a highly stable field emitter, which comprises applying a strong electric field of io'V/cm or more under an ultra-high vacuum after surface treatment with H2S at .degree.

2) T1CN emitter surface at 900-1400℃
After performing surface treatment with a gas containing H2S or S and surface treatment with 02 separately or simultaneously under
A method for manufacturing a highly stable field emitter, which comprises applying a strong electric field of 107 V/cm or more under ultra-high vacuum.

3) T1CN emitter surface, 900-1400
A highly stable field emitter characterized in that a strong electric field of 107 V/cm or more is applied under an ultra-high vacuum after surface treatment with H2S and surface treatment with C2H4 are applied separately or simultaneously at ℃. manufacturing method.

4) The TiCN emitter surface was separately subjected to surface treatment with H2S, surface treatment with 02, and surface treatment with C2H4 at 900 to 1400 °C, e.g., H2S-02.
→C2H4, H2S→C2H4→02. C2H4→H
2S→021 C2H4→02→H2S rO2→C2
After applying H4-H2S, or 02→H2S→C2H, + in the order or simultaneously, under ultra-high vacuum, 107V/c
A method for manufacturing a highly stable field emitter, characterized by applying a strong electric field of m or more.

The T1CN emitter used in the present invention is 9, for example, 0.2X0 cut from titanium carbonitride single crystal Rondo.
．． The tip of a 2 x 3 mm rectangular parallelepiped was polished to about 0.0 mm by electrolytic polishing.
The tip diameter was 1 μm, and this emitter was heated under ultra-high vacuum for 1 μm.
A T1CN<110> emitter whose surface has been cleaned by flash heating at 500°C is used. The emission pattern is as shown in FIG. Note that the shaded area in the figure represents the d-light part of the electron beam.

TiCN < 110 with such a clean surface
>Heating the chip in H2S gas, e.g., at 900-1400<0>C under 10-'Torr. Heating time is 2L (
Langmuir) (L = 10-6TorrX1se
c) Select so that it is or more. When the heating temperature is below 900°C and above 1400°C, the emission pattern is the same as that from a clean surface, and the electron emission characteristics are not improved. Therefore, the heating temperature is 900-1
The temperature needs to be 400°C.

After this treatment, under ultra-high vacuum, the total current was increased to about 10
When the electron beam is radiated (a strong electric field is applied) at μA for 30 minutes or more, the emission pattern changes as shown in FIG. 2.

Note that the dotted line portion indicates the emission pattern from the clean surface before surface treatment.

The Ti CN field emitter treated in this way has a current noise of less than ±0.296 and a drift of ±0.
．． It exhibits excellent characteristics of 2%/hr or less, as shown in FIG. 3 (tal).

The gas treatment may be performed by combining the earlier H2S treatment, the 02 treatment, and/or the treatment with C2H4 gas.

Examples of these are as follows.

1) After the above H2S treatment, 900 to 140
Heat at 0°C. The heating time at that time should be selected to be 5L or more. Conversely, the H2S gas treatment may be performed after the 02 treatment or at the same time. If they are carried out at the same time, the amount of introduced 02 gas is adjusted to 02: 5 L or more and H2S: 2 L or more.

2) Instead of the 02 process in 1) above, a process using C2H4 gas (gas introduction amount of 50 L or more) can be performed in the same way.

3) H2S treatment + 02 treatment and C2H4 treatment may be performed simultaneously or separately.

In addition, when performing methods 1), 2), and 3) above,
Field emitters exhibiting excellent stability can be manufactured regardless of the orientation of the titanium carbonitride single crystal.

Example 1゜T1Co with tip diameter of 0.1 μm, vsNo, o+ < 1
10> The field emitter was set under ultra-high vacuum and flash heated to 1500°C to obtain a clean surface. H2S gas was introduced into this system to create a vacuum of 1 x 1 O-6 Torr, and then heated at 1100°C for 10 seconds. (lO
L exposure amount), and then radiated a total current of about 10 μA for 30 minutes under ultra-high vacuum (applying a strong electric field of 107 V/cm or more), changing the emission pattern from Fig. 1 to the pattern shown in Fig. 2. . The current noise of the field emitter obtained is less than ±0.296 under a vacuum degree of 5 x 10””’Torr c), and the drift is less than ±0.2%/hr.
Its electron emission characteristics were as shown in FIG. 3 1a).

Example 2゜Example 1. By the method of TiCoc+sNo, o+ < 1
10> After surface treating the feed emitter chip with H2S, C2H4 gas is introduced into this system, and IX1O
After setting the degree of vacuum to -6 Torr, it was heated at 1100° C. for 100 seconds. (100L exposure amount).

After that, Example 1. 10 under ultra-high vacuum as in
A strong electric field of 7 V/an or more was applied to change the emitter pattern from FIG. 1 to FIG. 2.

The current noise of the obtained field emitter was less than 10.296 at a vacuum level of 5 to 12 Torr, and the drift was less than ±0.2%/hr, and its characteristics are shown in Figure 3 (bl It was as shown in

Example 3゜Example 2. 02 was used in place of C 2 H4 in , and heated at 1100° C. for 20 seconds. (20L exposure amount Å
A field emitter was obtained in the same manner as in Example 2. The obtained field emitter is Example 2. It was similar to

Example 4゜Example 2. After C2H4 treatment in the same manner as above, evacuated to ultra-high vacuum again, 02 was introduced, and 1×10-εTor was applied.
After setting the vacuum degree to r, it was heated at 1100° C. for 20 seconds.

(Exposure amount: 20L) A field emitter was manufactured in the same manner as in Example 2. The characteristics of the obtained field emitter were similar to those in Example 2.

Effects of the Invention According to the method of the present invention, a field emitter exhibiting excellent stability can be easily manufactured from a titanium carbonitride single crystal.

[Brief explanation of drawings]

Figure 1 shows the emission pattern from the clean surface of a TiCogsNo, o+<110> field emitter after flash heating at 01500°C. Figure 2 shows the emission pattern from the field emitter after processing according to the method of the present invention. Figure 3 is a graph showing the relationship between the total current and time of the field emitter manufactured by the method of the present invention, and FIG.
FIG. 1bl shows the case where after the H2S treatment, the C2 mountain gas treatment was performed on the third layer. Patent applicant Goto, director of the Institute for Inorganic Materials, Science and Technology Agency
Excellent

Claims (1)

[Claims] 1) The surface of the titanium carbonitride single crystal emitter is 900 to 1
After surface treatment with gas containing H_2S or S at 400℃, under ultra-high vacuum, 10^7V/cm
A method for producing a titanium compound field emitter, characterized by applying a strong electric field of the above magnitude. 2) Titanium carbonitride single crystal emitter surface with 900~1
After performing surface treatment with a gas containing H_2S or S and surface treatment with O_2 separately or simultaneously at 400°C, applying a strong electric field of 10^7 V/cm or more under ultra-high vacuum. A method for producing a titanium compound field emitter characterized by: 3) Titanium carbonitride single crystal emitter surface with 900~1
After surface treatment with H_2S or S-containing gas and surface treatment with C_2H_4 or other hydrocarbon gas at 400°C, separately or simultaneously, the A method for producing a titanium compound field emitter, characterized by applying an electric field. 4) Titanium carbonitride single crystal emitter surface with 900~1
After surface treatment with a gas containing H_2S or S, a surface treatment with O_2, and a surface treatment with C_2H_4 or other hydrocarbon gas at 400°C, separately or simultaneously, under ultra-high vacuum at 10^7V. A method for manufacturing a titanium compound field emitter, which comprises applying a strong electric field of /cm or more.