JP6120182B2 - Both ends sealed short arc flash lamp - Google Patents

Description

  The present invention relates to a double-end sealed short arc flash lamp, and more particularly to a double-end sealed short arc flash lamp in which one sealed tube portion has a double tube structure.

A discharge lamp that performs flash lighting is widely used in industrial applications such as flash annealing in a semiconductor manufacturing process, and the lamp of the present invention is particularly used in an exposure process using vacuum ultraviolet light.
In the above exposure process, it is required to use light close to parallel light, which can irradiate a small area with high-density light in a short time, has relatively little unevenness in the directionality and distribution of light.
Up to now, in the same exposure process, a vacuum lamp having a vacuum tube shape as disclosed in Japanese Patent Application Laid-Open No. 2012-43736 (Patent Document 1) has been mainly used. This lamp has a smaller distance between main electrodes than a general lamp that performs flash lighting, and can be handled as a light source close to a point light source.

  However, in order to have a vacuum tube structure, it is necessary to seal both the main electrode and the trigger electrode (starting auxiliary electrode) at one end, and the connection part (base) to the device and the power source has a cylindrical structure In particular, the outer diameter is increased. For this reason, when the same lamp is used inside an optical system having a reflector or the like, there is a problem that a light shielding region due to a base structure or the like becomes large, and as a result, light output from the optical system is lowered.

With respect to these problems, Japanese Patent Application Laid-Open No. 2012-94362 (Patent Document 2) uses the so-called double-end sealed structure in which sealing portions are arranged on both sides of the lamp bulb, thereby reducing the above-described light-shielding region. Technology is shown.
As shown in FIG. 5, in a both-end sealed short arc flash lamp, a first sealing tube 2 and a second sealing tube 3 are connected to both ends of the arc tube 1. And the opening end part of the glass tube 4 for sealing is inserted in the said 2nd sealing tube 3, and both are welded.
A pair of first main electrode 5 and second main electrode 6 are disposed opposite to each other in the arc tube 1. The first main electrode 5 has a core wire 7 supported and sealed by means such as a step glass in the first sealing tube 2 and led out to the outside, while the second main electrode 5 6, the core wire 8 is supported and sealed by the sealing glass tube 4 by means such as step glass, and is led out to the outside.
A pair of auxiliary starting electrodes 10 and 11 are arranged between the main electrodes 5 and 6 in the arc tube 1, and the internal leads 12 and 15 and the external leads 13 and 16 are connected to the first electrodes. 2 In the welding region between the sealing tube 3 and the sealing glass tube 4, they are electrically connected via metal foils 14 and 17.

  According to such a both-end-sealed short arc flash lamp, the above-described light-shielding region can be reduced by disposing sealing portions at both ends of the lamp bulb.

However, in such a lamp, gases such as nitrogen, oxygen, carbon dioxide, and water vapor (hereinafter also referred to as mixed gas) that are atmospheric components are easily mixed in the manufacturing process. Oxidizes, and the generated oxide evaporates and adheres to the inner surface of the valve, thereby reducing the transmittance.
Further, if mixed gas is present around the auxiliary electrode, there is a problem that even if a high frequency high voltage is applied from the lighting circuit to the auxiliary electrode, the ionization efficiency of the gas around the auxiliary electrode is lowered and the starting characteristics are deteriorated.

JP 2012-43736 A JP 2012-94362 A

  In view of the above-mentioned problems of the prior art, the problem to be solved by the present invention is that a glass arc tube has a pair of main electrodes and a starting auxiliary electrode, and a first seal is formed at both ends of the arc tube. A stop tube and a second sealing tube, wherein the core wire of the first main electrode is sealed in the first sealing tube and led out of the arc tube, and the second sealing tube includes An opening end of a glass tube for sealing is inserted inside and welded to the second sealing tube, and the core wire of the second main electrode is sealed outside the arc tube in the glass tube for sealing. In the both-end-sealed short arc flash lamp that has been derived, the mixed gas in the arc tube is effectively adsorbed by the getter, and the evaporated getter does not adhere to the inner surface of the light emitting part, and in the getter storage container and arc tube. Abnormal discharge may occur between the internal lead of the extended starting auxiliary electrode To provide a free structure.

In order to solve the above-mentioned problems, a both-end sealed short arc flash lamp according to the present invention has a getter container fixed to the core wire of the main electrode in the first sealed tube, and the getter container is opened at one end side. An annular member having an annular recess, a metal which is a transpiration getter material is carried in the tubular recess, and the opening is arranged facing the sealing end side of the first sealing tube, A metal thin film made of a transpiration getter material is formed on the inner surface of the first sealing tube.
The getter container may be welded to the core wire of the first main electrode with a metal foil interposed.
Further, the getter container is fixed to the core wire by a bridge member straddling the getter container in a direction in which the core wire of the first main electrode extends.

According to the both-end-sealed short arc flash lamp of the present invention, the getter material evaporates by providing the getter container carrying the evaporable getter material in the annular recess in the sealed tube. Since the metal thin film is formed, the metal thin film adsorbs the mixed gas in the arc tube, thereby preventing the electrode from being oxidized and preventing a decrease in the transmittance of the arc tube due to the oxide.
In addition, since the mixed gas does not exist around the auxiliary starting electrode, the starting characteristic is kept good.

In addition, since the getter container is fixed in the first sealing tube, unlike the second sealing tube in which the internal lead of the starting auxiliary electrode extends, there is no abnormal discharge between the getter container and the internal lead, Furthermore, there is no short circuit between the getter material deposited on the first sealing tube and the internal lead to cause abnormal discharge.
In addition, when fixing the getter container to the electrode core wire in the first sealing tube, the opening of the tubular recess is directed to the sealing end side, so that the evaporated getter material is sealed at the sealing end in the first sealing tube. Since the film is formed on the portion side and is not formed on the light emitting portion, the light transmission efficiency from the light emitting portion is not lowered.

Cross-sectional view of a double-side sealed short arc flash lamp of the present invention 1 is an enlarged cross-sectional view of the main part of FIG. An example of how to attach a getter storage container Other examples of installation Cross-sectional view of a conventional double-end sealed short arc flash lamp

FIG. 1 is an overall cross-sectional view of a both-end sealed short arc flash lamp according to the present invention, and FIG. 2 is an enlarged cross-sectional view of the main part thereof.
The overall structure of the lamp is the same as that of the prior art shown in FIG. However, in the present invention, the getter container 20 is fixed to the core wire 7 of the first main electrode 5 extending into the first sealing tube 2.
The details are shown in FIG. 2, and the getter container 20 is composed of an annular member 21 made of metal such as molybdenum having an annular recess 22, and one end of the annular recess 22 is opened as a tubular opening 22a.

A getter material 23 is stored and supported in the annular recess 22. In the case of the present lamp, the getter material 23 is optimally a transpiration getter whose main component is barium because of its operating temperature.
For example, the three-component mixed metal powder of aluminum, barium, and nickel is accommodated in the annular recess 22 of the getter container 20.
The getter container 20 is inserted and arranged in the lamp. When the container is heated to a temperature higher than a certain temperature after the lamp is manufactured, the contained aluminum and nickel are melted and alloyed to release reaction heat. In this process, the temperature of the mixed barium rises above its melting point. As a result, barium evaporates from the annular opening 22a of the getter vessel 20 and adheres to the inner surface of the surrounding lamp, and a metal thin film of getter material is formed to give a function as a getter.

FIG. 3 shows how the getter container 20 is attached to the core wire 7 of the first main electrode 5.
Examples of these numerical values are as follows.
<Luminescent tube>
Material: Quartz glass, Maximum outer diameter: φ20mm, Wall thickness: 1.2mm
<First sealing tube>
Outer diameter: φ12mm, wall thickness: 1.2mm
<First main electrode>
Material: Tungsten, Maximum outer diameter: φ4mm
<Core wire>
Material: Tungsten, outer diameter φ2mm
<Getter container>
Material: Molybdenum, outer diameter 6mm, inner diameter 4mm, thickness 0.1mm
<Getter material>
Three components of aluminum, nickel, and barium, total amount of mixture: 0.1 mg
After containing the mixture of three components in a getter container, press and mold <metal foil>
Material: Nickel, thickness 0.1mm

In advance, a metal foil 25 is wound around a predetermined position of the core wire 7 (inside the first sealing tube 2 as shown in FIG. 1) and fixed to the core wire 7 by spot welding.
Then, as shown in FIG. 3A, the getter container 20 in which the getter material 23 is supported on the portion of the metal foil 25 of the core wire 7, and the tubular opening 20 a of the sealed end of the first sealing portion 2. Fit so that it faces the part side.
Next, as shown in FIG. 3B, the getter container 20 is tilted and fixed on the metal foil 25 by spot welding or the like in that state.
Thereby, the getter container 20 is fixed to the core wire 7 in the first sealing portion 2.
In addition, in this example, although what was welded with the bottom part side of the getter container 20 with respect to the core wire 7 and the front end side was shown, if sufficient fixing force is obtained, either It doesn't matter.

  FIG. 4 shows another method for attaching the getter container 20 to the core wire. In this example, the first main electrode 5 is fixed by a bridge member 28 straddling the getter container 20 in the direction in which the core wire 7 extends. The bridge member 28 is preferably a metal foil such as nickel. The metal foil 28 is disposed so as to straddle the getter container 20 and is fixed to the core wire 7 by spot welding on both sides of the getter container 20. is there.

1 and 2, the getter container 20 with the getter material 23 carried therein is arranged so that the opening 20 a is directed to the sealed end portion side in the first sealing portion 2. Thus, the core wire 7 of the first main electrode 5 is fixed.
With such an arrangement, as shown in FIG. 1, the getter container 20 is arranged in a region X that is shadowed by the first main electrode 5, thereby preventing effective emitted light from the lamp. There is nothing. Further, when the getter container 20 becomes high temperature after the lamp is completed and the getter material evaporates, a metal thin film 30 of the getter material is formed on the inner surface of the lamp. This metal thin film 30 is also hidden behind the above-mentioned emitted light. Formed in the region X, and does not reach the arc tube 1.

As described above, in the both-end sealed short arc flash lamp according to the present invention, the getter container having the getter material supported on the core wire of the first main electrode in the first sealed tube is provided. Even if gases such as nitrogen, oxygen, carbon dioxide, and water vapor are mixed in the arc tube, these can be adsorbed accurately by the getter material, and a lamp excellent in startability and luminous efficiency can be provided.
And since this getter container is provided in the first sealing tube, the internal lead of the starting auxiliary electrode does not extend, and no abnormal discharge occurs between them, and the metal of the getter material Even if the thin film is formed on the inner surface of the sealing tube, there is no short circuit with the internal lead.
Furthermore, since the opening of the getter container is fixed toward the sealed end portion of the first sealing tube, the metal thin film of the getter material formed on the inner surface of the lamp does not reach the arc tube. There is no hindrance to the light.

DESCRIPTION OF SYMBOLS 1 Light-emitting tube 2 1st sealing tube 3 2nd sealing tube 4 Glass tube for sealing 5 1st main electrode 6 2nd main electrode 7 Core wire of 1st main electrode 8 Core wire of 2nd main electrode 10 First start auxiliary electrode 11 Second start auxiliary electrode 12 Internal lead of first start auxiliary electrode 13 External lead of first start auxiliary electrode 14 Metal foil 15 Internal lead of second start auxiliary electrode 16 Second lead External lead of start auxiliary electrode 17 Metal foil 20 Getter material container 21 Annular member 22 Tubular recess 22a Annular opening 23 Getter material 25 Metal foil 28 Bridge member 30 Getter material metal thin film X Area that is behind the emitted light

Claims (3)

The glass arc tube has a pair of main electrodes and a starting auxiliary electrode, and includes a first sealing tube and a second sealing tube at both ends of the arc tube,
In the first sealing tube, the core wire of the first main electrode is sealed and led out of the arc tube,
The second sealing tube is welded to the second sealing tube by inserting an opening end of a sealing glass tube into the second sealing tube,
In the sealing glass tube, in the both-end sealed short arc flash lamp in which the core wire of the second main electrode is sealed and led out of the arc tube,
An internal lead and an external lead of the starting auxiliary electrode are electrically connected via a metal foil in a welding region between the second sealing tube and the sealing glass tube,
A getter container is fixed to the core wire of the main electrode in the first sealing tube,
The getter container is an annular member having an annular recess that is open at one end.
A metal that is a transpiration type getter material is carried in the annular recess,
The opening is disposed facing the sealing end of the first sealing tube;
A both-end sealed short arc flash lamp, wherein a metal thin film made of a transpiration getter material is formed on the inner surface of the first sealing tube.
  2. The both-end sealed short arc flash lamp according to claim 1, wherein the getter container is welded to the core wire of the first main electrode with a metal foil interposed therebetween. 2. The both-end sealed short arc flash lamp according to claim 1, wherein the getter container is fixed to the core wire by a bridge member straddling the getter container in a direction in which the core wire of the first main electrode extends.