Patent Application
20120280137
1. Field of the Invention
The present invention relates to an ion implanting system, and more particularly to an ion implanting system which is able to obtain relevant parameters of an ion beam during ion implantation.
2. Description of the Prior Art
In a fabrication process for integrated circuits, an ion implanting system is configured for implanting an impurity into a semiconductor material. An ion implanting process includes ionizing required impurity elements, selecting the ions with a desired mass/charge ratio, targeting the selected ions toward a substrate, such as a semiconductor wafer, and implanting the impurity elements into the substrate.
In the ion implanting process, the implanted amount of impurity elements must be precisely controlled. The ion implanting process involves first detecting relevant parameters of an ion beam (such as ion beam density) by a detector, and then based on the parameters measured by the detector adjusting fabrication parameters of the system to make the relevant parameters of ion beam meet a desired setting value, and then after substrates are placed on the projection region of ion beam, implanting ions. Relevant parameters of ion beam can not be obtained during ion implantation; consequently, the ion implanting system of the prior art can not justify the fabrication parameters of the system to control implant process without holding the implant first.
According to the foregoing descriptions, it is highly desirable to obtain relevant parameters of the ion beam as a basis for adjusting the fabrication parameters during ion implantation.
The present invention is directed to an ion implanting system including a detector which can pass across a projection region of an ion beam to obtain relevant parameters of the ion beam during ion implantation.
Therefore, according to the relevant parameters of the ion beam obtained by the detector, the system of the present invention may immediately adjust fabrication parameters to obtain a better effect of ion implantation.
In one embodiment, the proposed ion implanting system includes an ion beam generator, a mass separation device, a holder device and a first detector. The ion beam generator is configured for generating a first ion beam. The mass separation device is arranged at the downstream side of the first ion beam and configured for isolating a second ion beam comprising required ions from the first ion beam. The holder device is arranged at the downstream side of the second ion beam and configured for holding a least one substrate, wherein the holder device and the second ion beam reciprocate relative to each other along a first direction to make the substrate pass across a projection region of the second ion beam. The first detector reciprocates relative to the second ion beam and passes across the projection region of the second ion beam to obtain relevant parameters of the second ion beam.
The objective, technologies, features and advantages of the present invention will become apparent from the following description in conjunction with the accompanying drawings wherein certain embodiments of the present invention are set forth by way of illustration and example.
The foregoing conceptions and their accompanying advantages of this invention will become more readily appreciated after being better understood by referring to the following detailed description, in conjunction with the accompanying drawings, wherein:
a,
The detailed explanation of the present invention is described as follows. The described preferred embodiments are presented for purposes of illustrations and description, and they are not intended to limit the scope of the present invention.
Referring to
The holder device 13 is arranged on the downstream side of the second ion beam 112, and configured for holding a least one substrate 100. According to an embodiment, the substrate 100 may be a semiconductor wafer. The holder device 13 and the second ion beam 112 reciprocate relative to each other along a first direction, making the substrate 100 pass across the projection region of the second ion beam 112 in a reciprocating manner. In other words, the second ion bean 112 can scan across the entire substrate 100. According to an embodiment, the holder device 13 is connected with a driving device 15. The driving device 15 drives the holder device 13 to reciprocate relative to the second ion beam 112 along the first direction, making the substrate 100 pass across the projection region of the second ion beam 112 in a reciprocating manner. Preferably, the driving device 15 also drives the holder device 13 to move along a second direction, making the second ion beam 112 scan across the entire substrate 100. According to an embodiment, the first direction and the second direction are substantially perpendicular to each other, making the second ion beam 112 to comprehensively scan the substrate 100 along the left-right direction and the up-down direction. It should be noted that the moving path of the substrate 100 along the first direction may be in straight line or arc. In addition, the second direction may be parallel, for the isocentric scan case, to the plane where the substrate lies, or at an angle to the plane for the non-isocentric scan case.
The first detector 14a reciprocates relative to the second ion beam 112 and passes across the projection region of the second ion beam 112. According to an embodiment, the first detector 14a and the substrate 100 move together, and therefore, the first detector 14a can obtain relevant parameters of the second ion beam 112. For example, the relevant parameter of the second ion beam 112 may be the beam current, parallelism, incident angle, ion beam density, charging sensor response, ion beam profile shape of the second ion beam, or the combination thereof. Since the first detector 14a passes across the projection region of the second ion beam 112, the complete relevant parameters of the second ion beam 112 can be obtained even though the shorter axis of the detection zone of the first detector 14a is smaller than the projection region of the second ion beam 112. In other words, the dimension of the first detector 14a in the first direction can be significantly reduced while not affecting the ability of acquiring the relevant parameter of the second ion beam 112. According to an embodiment, the first detector 14a may be a Faraday cup.
Referring to
Referring to
According to an embodiment, the first detector 14a is connected with the holder device 13 in a fixed manner, as illustrated in
Referring to
Referring to
To summarize the foregoing descriptions, ion implanting system of the prevent invention includes a first detector which can pass across a projection region of an ion beam to obtain relevant parameters of the ion beam during ion implantation. Therefore, the system of the present invention may immediately adjust fabrication parameters or holding the implant process upon detecting out-of control cases based on the relevant parameters of the ion beam obtained by the detector to obtain a better effect of ion implantation.
While the invention is susceptible to various modifications and alternative forms, a specific example thereof has been shown in the drawings and is herein described in detail. It should be understood, however, that the invention is not to be limited to the particular form disclosed, but to the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the appended claims.
