JP3395265B2 - Neutral particle removal method and ion implanter in ion implanter - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing neutral particles in an ion implanter and an ion implanter. INDUSTRIAL APPLICABILITY The present invention can be used, for example, as an ion implantation technique used when manufacturing electronic materials (semiconductor devices and the like).

[0002]

2. Description of the Related Art As shown in FIGS. 4 and 5, an ion implantation apparatus conventionally used for manufacturing a semiconductor device or the like has an ion source section 1 for generating ions and a desired ion selection section. The analyzer magnet unit 2, an accelerating unit (accelerating tube 7) for accelerating desired ions, and an end station 84 for injecting ions into the substrate are composed of four main parts.

Conventional ion implanters include a high current ion implanter as shown in FIG. 5 and a medium current ion implanter as shown in FIG. The former high-current ion implanter has low energy (about 10 KeV or less).
In the case of high current injection (beam current is in the order of mA) in (3), a neutral beam is likely to be formed in the slit portion shown in FIG. Unlike the medium current ion implanter, the high current ion implanter generally does not have an electrode such as a beam filter or a 7 ° deflection mechanism, so that the neutral beam tends to be implanted on the substrate to cause overdose. In the case of the medium current device, the neutral particles are rarely directly driven into the substrate, but the neutral particles are suspended in the accelerating tube beyond the electrodes such as the beam filter and enter the ionizing beam, which is desired. It becomes a factor that ions of external energy are injected.

Further, when the ion beam passes through the analyzer magnet section 2, sputtered particles generated by beam sputtering the apparatus member or secondary ions due to the sputter may be implanted into the substrate as heavy metal contamination. . Secondary ions generated by sputtering at this time are considered to be electrically removable by a beam filter or an Einzel lens because they are charged particles, but neutral particles generated by sputtering cannot be removed by these electrodes.
Therefore, it is considered that there is a tendency that it is taken into the beam, converted into a charge, and is implanted into the substrate to cause heavy metal contamination.

[0005]

It is an object of the present invention to solve the above-mentioned problems of the prior art, to efficiently remove neutral particles, and to prevent adverse effects on the object to be treated. It is an object to provide an injection device.

[0006]

According to the invention of claim 1 of the present application, when the ions extracted from the ion source part are guided to the ion implantation irradiation port through the analyzer magnet, they are placed between the analyzer magnet and the ion implantation irradiation port. A method for removing neutral particles in an ion implantation apparatus configured to ionize neutral particles by the ionizing means and remove the ionized neutral particles, which achieves the above object Is.

According to a second aspect of the present invention, in an ion implantation apparatus configured to guide ions extracted from an ion source section to an ion implantation irradiation port through an analyzer magnet, ionization is performed between the analyzer magnet and the ion implantation irradiation port. An ion implantation apparatus comprising means and means for removing ionized neutral particles, by which the above object is achieved.

According to the present invention, in the ion implantation technique, after the variable slit between the analyzer magnet section and the acceleration tube, an ionization means such as a microwave generation section made of quartz tube is installed at the positions shown in FIGS. 4 and 5. However, by passing the ion beam through the microwave, neutral particle components (including sputtered particles from equipment members) that could not be removed by electrodes such as beam filters and Einzel lenses so far.
Can be ionized at that portion, and neutral particles in the beam can be electrically efficiently removed by a removing means such as a beam filter or an Einzel lens.

[0009]

According to the present invention, since the neutral beam is ionized by the ionizing means, neutral particles which could not be removed by the conventional method can be efficiently removed by the removing means such as electrical means.
As a result, it is possible to prevent the neutral beam from reaching the object to be processed and adversely affecting it.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. However, as a matter of course, the present invention is not limited to the following examples.

The system configuration of the ion implantation apparatus of this embodiment is shown in FIG. As shown in FIG. 1, the ion implantation technique in the present embodiment is designed so that when the ions extracted from the ion source part 1 are guided to the ion implantation irradiation port 3 through the analyzer magnet 2, the analyzer magnet 2 and the ion implantation irradiation port 3 are connected to each other. An ionizing means 4 is provided between the ionizing means 4 and the neutralizing particles are ionized by the ionizing means 4 to remove the ionized neutral particles. In addition, in the ion implantation apparatus configured to guide the ions extracted from the ion source unit 1 to the ion implantation irradiation port 3 through the analyzer magnet 2, the ionization means 4 is ionized between the analyzer magnet 2 and the ion implantation irradiation port 3. The neutral particle removing means 5 is provided.

In an ordinary plasma ion implantation apparatus, as shown in FIG. 2, a high frequency is applied between both electrodes by a high frequency generating means 90, and a gas between them is excited to create a plasma state to form a plasma region II. And Code III
Indicates gas filling.

In the present embodiment, as shown in FIG. 3, a quartz tube IV through which the beam V is passed is provided with a microwave generator which is the ionization means 4. Since the ion beam contains neutral beams and ions with different energies, these are ionized, and the beam filter and E-lens after this do not allow undesired ions to jump into the accelerating tube side. To do so. Ionization is set to such an extent that the required ion beam can be selectively removed.

In the present embodiment, as shown in FIG. 1, in particular, by incorporating the microwave generating portion which is the ionizing means 4 in front of the Einzel lens which is the removing means 5 and the like,
Neutral particles contained in the beam (including sputtered particles)
Is ionized, and a state in which it is easily cut by the electrode of the Einzel lens which is the removing means 5 is created. The ionization means 4 and the removal means 5 enable the neutral particle removal system I.
Make up. Ions of different energies do not tune to the microwave frequency (set to a frequency synchronized with the extraction voltage), and become ions of energy different from the extraction voltage, and the removal means 5 such as the Einzel lens And efficiently removed.

In this embodiment, the ionization means 4 is arranged at the rear stage of the analysis slit 61 and the variable slit 62. In FIG. 4 and FIG. 5, it is arranged at the position of.

In the present embodiment, as described above, after the variable slit 62 between the analyzer magnet section 2 and the accelerating tube 7, the quartz tube made of microwave is used as the ionizing means 4 at the position of the reference numeral in FIGS. By installing a generator (see Fig. 3) and allowing the ion beam to pass through the microwave, neutral particle components (apparatus that could not be conventionally removed by an electrical method using electrodes such as a beam filter or an Einzel lens) It is possible to ionize (including sputtered particles from a member) and electrically and efficiently remove unnecessary neutral particles in the beam by means of the beam filter or Einzel lens, which is the removing means 5. .

According to this embodiment, the following effects are brought about. (1) A microwave quartz tube as the ionization means 4 is shown in FIG.
By providing after the analysis slit in the part of FIG. 5, the particles neutralized up to that part are ionized by microwaves,
After that, it can be electrically and efficiently removed by the removing means 5 such as electrodes. It can be said that this is particularly effective for low energy high current injection in which the defect of the neutral beam was large. (2) When the sputtered particles from the device member reach the substrate through the electrodes (beam filter, etc.), the sputtered particles are intentionally ionized by the microwave by the ionization means 4, and the beam filter, the Einzel lens, etc. are removed. It can be removed by means 5 so as not to go toward the substrate. (3) In divalent ion implantation, in addition to electrodes such as a beam filter, it is possible to prevent unwanted mixing of energetic ions by microwaves. (4) Since unnecessary mixing of ions is eliminated, it is possible to implant the required impurity ions with high purity.

[0018]

As described above, according to the present invention, neutral particles in the implantation beam of ion implantation can be efficiently removed,
It was possible to provide a method for removing neutral particles in an ion implantation apparatus and an ion implantation apparatus that do not adversely affect the object to be processed.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of an ion implantation apparatus according to a first embodiment.

FIG. 2 is a diagram illustrating the principle of plasma generation.

FIG. 3 is a diagram showing a configuration for removing neutral particles in Example 1.

FIG. 4 is a schematic diagram showing a configuration of an ion implantation device (medium current device).

FIG. 5 is a schematic diagram showing a configuration of an ion implantation device (high current device).

[Explanation of symbols]

1 Ion source part 2 Analyzer magnet 3 Ion injection irradiation port 4 Ionization means (microwave generation part) 5 Ionized neutral particle removal means (Einzel lens, beam filter)

Claims (2)

(57) [Claims] 1. An ionization means is provided between an analyzer magnet and an ion injection irradiation opening when the ions extracted from the ion source are guided to the ion injection irradiation opening through the analyzer magnet, and the neutral particles are ionized by this ionization means. Then, the method for removing neutral particles in an ion implantation apparatus configured to remove the ionized neutral particles. 2. An ion implantation apparatus configured to guide ions extracted from an ion source section to an ion implantation irradiation port through an analyzer magnet, wherein an ionization means and an ionized neutral are provided between the analyzer magnet and the ion implantation irradiation port. An ion implantation apparatus comprising a particle removing means.