JPH0668286U - Ion implanter - Google Patents

Abstract

(57) [Summary] [Objective] To provide an ion implantation apparatus for a Barnass type ion source capable of achieving a long life of the ion source. [Structure] Two filaments 2 are mounted facing each other in an arc chamber 1 of a Barnus-type ion source. By connecting a negative electrode to the unused filament, the unused filament and the filament shield 7
The role of the filament reflector 8 in the conventional structure.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an ion implantation device for generating plasma.

[0002]

[Prior art]

 3 and 4 briefly show the structure of a plasma generation chamber (arc chamber) of a Barnus-type ion source in a conventional ion implantation apparatus. This Barnus-type ion source generates ions in the arc chamber 1, a slit is provided in one wall of the arc chamber 1, and positive charge ions are extracted from the slit by an extraction voltage of several tens keV.

Here, the ion generation will be briefly described. In FIGS. 3 and 4, first, a current of about 200 A is applied to the filament 2 to emit thermoelectrons, and in the case of a gaseous source material or a solid source, the solid is heated by a heater to be evaporated. The substance is introduced into the arc chamber 1 through the source gas inlet 3 or the metal vapor inlet 4. As a result, the thermoelectrons accelerated by the voltage between the filament 2 and the arc chamber 1 collide with the introduced source gas and are ionized into free electrons and ions having a positive charge. At this time, since a thermoelectron makes a spiral motion by applying a magnetic field from the outside, it is possible to increase the probability of collision between the thermoelectron and the gas molecule.

[0004]

[Problems to be solved by the device]

 By the way, one of the performance improvements required for the above-mentioned Varnas type ion source is extension of the life of the source. The source lifetime is the time that the beam can be emitted without exposing the source to the atmosphere.

There are two main factors that determine the life of the source. One is the exchange of the filament due to the consumption of the filament 2, and the other is the source of the filament insulator 5 and the reflector insulator 6. It is that gas or metal vapor adheres and deteriorates their insulation.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to provide an ion implantation apparatus of a Barnass type ion source capable of achieving a long life of the ion source.

[0007]

[Means for Solving the Problems]

 According to the present invention, two filaments are mounted facing each other in the arc chamber of the Barnass type ion source in the ion implantation device, and the negative electrode is connected to the filament on the unused side. It is possible to obtain an ion injecting device characterized in that the filament and the filament shield on the side also serve as the filament reflector.

[0008]

【Example】

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

The ion implanter according to the present invention, as shown in the schematic configuration of FIGS. 1 and 2, has two filaments 2 mounted facing each other in an arc chamber 1 of a Varnas type ion source. . Like the conventional filaments, these filaments 2 and the filament shield 7 via the filament insulator 5 are respectively configured so as to be insulated from the arc chamber 1.

In addition, in FIG. 1 and FIG. 2, when the filament in use is consumed and needs to be replaced, the + side of the filament power supply 9 is changed to another filament without breaking the vacuum. Reconnect.

Further, here, a negative electrode is connected to the unused filament, and the unused filament and the filament shield 7 serve as the filament reflector 8 in the conventional structure.

[0012]

[Effect of device]

 As described above, according to the present invention, the life of the filament of the arc chamber can be doubled, so that the life of the ion source can be extended.

[Brief description of drawings]

FIG. 1 is a schematic front sectional view of an arc chamber according to an embodiment of the present invention.

FIG. 2 is a schematic side sectional view of an arc chamber according to an embodiment of the present invention.

FIG. 3 is a schematic front sectional view of a conventional arc chamber.

FIG. 4 is a schematic side sectional view of a conventional arc chamber.

[Explanation of symbols]

 1 Arc Chamber 2 Filament 3 Source Gas Inlet 4 Metal Vapor Inlet 5 Filament Insulator 6 Reflector Insulator 7 Filament Shield 8 Filament Reflector 9 Filament Power Supply

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H01L 21/265

Claims (1)

[Scope of utility model registration request] 1. In an arc chamber of a Barnass type ion source in an ion implantation apparatus, two filaments are mounted so as to face each other, and a negative electrode is connected to a filament on the unused side, and the filament on the unused side is connected. An ion implanter characterized in that the filament and the filament shield also serve as the filament reflector.