Ion implantation device

Details Ion implantation device Ion implantation device

1998-11-25

2001-06-05

Berman, Jack (Department: 2881)

Radiant energy

Irradiation of objects or material

Irradiation of semiconductor devices

C250S398000, C250S3960ML

Reexamination Certificate

active

06242750

ABSTRACT:

PRIORITY
This patent application claims priority under the Paris Convention of Japanese Patent Application, Heisei 9, Patent Application No. 328781, naming as inventors Yuhji Takahashi and Kohji Inada, filed Nov. 28, 1997 with the Japanese Patent Office in the name of Sumitomo Eaton Nova, on behalf of the inventors.
TECHNICAL FIELD OF THE INVENTION
The present invention pertains to ion implantation equipment. It relates to ion implantation equipment in which a high beam current can be obtained even in a lower energy region.
BACKGROUND
In recent years, the semiconductor industry came to realize the necessity for ion implantation equipment in which a high beam current can be obtained even in the lower energy region, so that a shallow junction can be fabricated using boron ions and so forth.
An example is disclosed in Patent Application Publication No. Hei 4-6740. In this ion implantation equipment, a large current of an ion beam is implanted into a substrate through a beam transport system which contains mass analyzer tubes. A deceleration static electrode lens system is provided and consists of three electrodes, having a hole, to provide a large potential gradient and two electrodes, having a hole, for acceleration and deceleration. An ion source is kept at a positive potential at a few kV or higher, but below 20 kV, against the ground potential. The beam transport system between the ion source and the deceleration static electrode lens system is kept at a negative potential at a few or several tens of kV against the ground potential. The first electrode having a hole in the deceleration static lens system is kept at the same negative potential at a few or several tens of kV as the beam transport system. The third electrode having a hole in the deceleration static lens system is kept at the ground potential. The second electrode having a hole in the deceleration static lens system is kept at a middle potential between these of the first and third electrode having a hole. The fourth electrode having a hole in the deceleration static lens system is kept at a negative potential. The fifth electrode having a hole in the deceleration static lens system is kept at the ground potential. The deceleration static lens system is used as a convergent lens as well as for its deceleration function.
In such ion implantation equipment, a high voltage case needs to surround the ion source, an ion extractor system, the mass analyzer tubes, the beam transport system and so forth, so that all components within the high voltage case are insulated from the ground potential. In the above ion implantation equipment, this is achieved by floating the entire high voltage case from the remaining equipment. Hence, the equipment becomes large and manufacturing costs of such equipment becomes expensive. These are the issues.
The purpose of the present invention is to provide ion implantation equipment in which the beam current in a lower energy region can be increased without making such equipment very large and expensive to manufacture.
SUMMARY
The ion implantation equipment of the present invention has the characteristics in that its vacuum chamber contains an ion source and an extractor electrode system. In said vacuum chamber a liner which covers said ion source and extractor electrode system is provided across an insulator. Further in said vacuum chamber a beam guide, which guides the ion beam out of said extractor electrode system, is provided across an insulator. Around said ion beam guide, a mass analyzer magnet is arranged, while a disk chamber is provided across an insulator at one end of the ion beam guide, and an deceleration means, which converges and decelerates the ion beam, is arranged within said disk chamber.
Furthermore, said deceleration means has the characteristics in that it has an extension tube which extends out of the end of said beam guide and three electrode apertures are arranged at the exit end of said extension tube, wherein these three electrode apertures converge and decelerate an ion beam.
Further, it is preferred that the middle electrode aperture of said three electrode apertures is designed so that the aperture width can be switched according to what ions pass through it.
Moreover, it is preferred that a positive voltage is applied to said ion source, a negative voltage is applied to said extractor electrode system, a lower negative voltage than that for said extractor electrode system is applied to said liner and a lower negative voltage than that for said liner is applied to said beam guide.
In the present invention, the beam current in a lower energy region is increased by employing a simple external insulation method to accelerate and decelerate an ion beam within the design of the conventional mean line.


REFERENCES:
patent: 5747936 (1998-05-01), Harrison et al.
patent: 5780863 (1998-07-01), Benviste et al.
patent: 5883391 (1999-03-01), Adibi et al.
patent: 5932882 (1999-08-01), England et al.

Affiliated with

Also associated with

Rating

Ion implantation device does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Ion implantation device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ion implantation device will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2531915