KR20040099860A - Ion implanter - Google Patents

Abstract

PURPOSE: An ion implantation apparatus is provided to monitor whether suppression voltage is normally supplied or not by installing a suppression voltage monitoring contactor in a deceleration bar in addition to a suppression voltage output contactor. CONSTITUTION: An ion implantation apparatus includes a source part(300), an ion beam line part(400), a deceleration suppression supply contactor(140), and a deceleration suppression monitor contactor(150). The source part generates ions to be doped into the wafer. The ion beam line part includes an acceleration column(200) for accelerating or decelerating the generated ions. The deceleration suppression supply contactor supplies a deceleration suppression voltage to the acceleration column. The deceleration suppression monitor contactor monitors the deceleration suppression voltage. The deceleration suppression supply contactor and the deceleration suppression monitor contactor simultaneously come into contact with the acceleration columns and electrically connected to a deceleration suppression power supply part(600).

Description

Ion implanter {ION IMPLANTER}

The present invention relates to an ion implantation apparatus, and more particularly, to an ion implantation apparatus having a suppression voltage monitoring system capable of monitoring whether the suppression voltage is supplied.

Ion implantation has been developed as a standard technique for implanting dopants into semiconductor wafers. Ion implantation utilizes an ion implantation device that ionizes a desired dopant in an ion source, accelerates these ions to form an ion beam of a given ion energy, and directs the ion beam toward the surface of the wafer.

The ion implantation apparatus includes a source part, an ion beam line part, an acceleration column, and an end station part. The source portion generates ions of the impurity element to be doped. The ion beamline portion selects ions to be implanted into the wafer, and accelerates or decelerates the selected ions to give energy to the wafer to be doped to a desired depth. The end station is where the wafer to be implanted is placed. The ion beamline portion includes an acceleration column for accelerating or decelerating selected ions between the end station portion. The acceleration column is provided with an acceleration ring for applying an acceleration voltage or a deceleration voltage. By this ion implantation device, ions containing energy in the ion beam are stored in the crystal lattice of the semiconductor material to penetrate the wafer, i.e., the bulk of the semiconductor material, to form the desired conductive layer.

In the ion implantation process required for semiconductor device manufacturing, it is considered that ion implantation energy, dose and ion should be most importantly managed. The ion implantation energy is determined by the sum of the extraction of the source part and the acceleration or deceleration of the ion beam line part. Acceleration of the ion implantation energy in the ion beam line part is called an acceleration mode, and conversely, in the case of decelerating the ion implantation energy, it is called a deceleration mode.

The ion implantation process extracts the ion beam by accelerating to an extraction voltage of 40 kV, for example, to extract the ion beam. After the ion beam is extracted, the ion implanter is typically used in an acceleration mode for a high energy process of 40 kV or more and in a deceleration mode for a low energy process of 30 kV or less. The transition from the acceleration mode to the deceleration mode in the ion implantation process using the ion implantation apparatus uses a device called a swing arm assembly.

Switching from the acceleration mode to the deceleration mode, as shown in FIG. 1, connects the deceleration bar 10 of the swing arm assembly to the acceleration ring 22 of the acceleration column 20. Let's do it. Then, the deceleration mode is implemented by supplying the deceleration voltage to the acceleration ring 22 through the deceleration voltage output contactor 16 of the deceleration bar 10. Here, a deceleration suppression contactor 14 for applying a suppression voltage to the acceleration column 20 to the deceleration bar 10 to prevent focusing of the ion beam and generation of secondary electrons. contactor) is provided. Reference numeral 12 denotes a terminal ground contactor 12.

However, the following problems exist in the related art. The ion implantation process was performed by checking the switch to the deceleration mode as a signal for operating the deceleration bar of the conventional swing arm assembly. However, when the ion implantation device is used alternately between the acceleration mode and the deceleration mode, the frequency of the forward and retract operation of the deceleration bar is increased, thereby causing misalignment between the deceleration bar and the acceleration ring.

However, even when the suppression voltage is not actually supplied to the acceleration column due to a misalignment between the deceleration bar and the acceleration ring, the suppression voltage is determined to be supplied even when the suppression voltage is actually supplied. This is because it was not possible to monitor and feed back the suppression voltage to the deceleration bar applying the suppression voltage. In other words, the deceleration bar was not provided with a sensing device, and was designed to supply power to the acceleration column unilaterally through only one deceleration suppression contactor.

As described above, when the ion implantation process is performed in the deceleration mode without the deceleration suppression voltage being applied, the focusing of the ion beam is out of the normal form. As a result, the density of the ion beam is biased toward either side of the wafer, and there is a problem that uniform ion injection into the wafer is not achieved.

Accordingly, the present invention has been made to solve the above-mentioned problems in the prior art, an object of the present invention is to provide an ion implantation device having a suppression voltage monitoring system that can be monitored by feeding back the suppression voltage during the deceleration mode ion implantation process In providing.

1 is a view schematically showing an ion implantation apparatus according to the prior art.

2 is a view showing an ion implantation apparatus according to the present invention.

3 is a cross-sectional view showing a contactor in the ion implantation apparatus according to the present invention.

Explanation of symbols on major parts of drawings

100; Deceleration bar

120; Terminal ground contactor

140; Deceleration suppression supply contactor

150; Deceleration suppression monitor contactor

160; Deceleration voltage output contactor

200; Acceleration column

220,220a; Acceleration ring

300; Source part

400; Ion beamline part

500; Endstation part

600; Deceleration suppression power supply part

610; Supply means

620; Feedback means

The ion implantation apparatus according to the present invention for achieving the above object is characterized in that the deceleration suppression voltage monitor contactor is further installed on the deceleration bar to monitor and feed back the suppression voltage.

An ion implantation apparatus according to a preferred embodiment of the present invention, an end retention portion on which the wafer to be doped is placed; A source unit generating ions of elements to be doped into the wafer; An ion beam line unit including an acceleration column for accelerating or decelerating the generated ions; And a deceleration bar including a deceleration suppression supply contactor for supplying a deceleration suppression voltage to the acceleration column, and a deceleration suppression monitor contactor capable of monitoring the deceleration suppression voltage.

The deceleration suppression supply contactor and the deceleration suppression monitor contactor are simultaneously contacted with the acceleration column, and are electrically connected to the deceleration suppression power supply unit.

The deceleration suppression supply contactor is electrically connected to the deceleration suppression power supply unit by a supply means, and the deceleration suppression monitor contactor is electrically connected to the deceleration suppression power supply unit by a feedback means.

Each one of the supply means and the feedback means is characterized in that each one of a wired means and a wireless means.

The deceleration bar further comprises a terminal ground contactor and a deceleration voltage supply contactor.

According to the present invention, since the suppression voltage monitoring contactor is additionally installed in the deceleration bar in addition to the suppression voltage supply contactor, monitoring and feedback of whether the suppression voltage is normally supplied can be performed.

Hereinafter, with reference to the accompanying drawings an ion implantation apparatus according to a preferred embodiment of the present invention will be described in detail.

The invention is not limited to the embodiments described herein but may be embodied in other forms. The embodiments introduced herein are provided to make the disclosed contents thorough and complete, and to fully convey the spirit and features of the present invention to those skilled in the art. In the drawings, each device is shown exaggeratedly and schematically, for clarity of the invention. Each device may also be equipped with a variety of additional devices not described in detail herein. Like reference numerals denote like elements throughout the specification.

(Example)

2 is a view showing an ion implantation apparatus according to the present invention, Figure 3 is a cross-sectional view showing a contactor in the ion implantation apparatus according to the present invention.

In the ion implantation apparatus according to the preferred embodiment of the present invention, as shown in FIG. 2, the source part 300, the ion beam line part 400, and the end station part 500 are provided. part). The ion implantation ionizes a desired dopant in an ion source using the above-described ion implantation device, and accelerates these ions to form an ion beam of a given ion energy so that the ion beam is directed toward the surface of the wafer. At this time, ions containing energy in the ion beam are stored in the crystal lattice of the semiconductor material so as to penetrate through the bulk of the wafer to form a desired conductive layer.

The source unit 300 generates ions of an impurity element to be doped, for example, boron (B) or phosphorus (P). The ion beam line unit 400 selects ions to be injected into the wafer, and accelerates or decelerates the selected ions to give energy to the wafer to be doped to a desired depth. The end station part 500 is where the wafer to be ion implanted is placed. The ion beam line unit 400 includes an acceleration column 200 for accelerating or decelerating ions selected from the end station unit 500. The acceleration column 200 is provided with an acceleration ring 220 for applying an acceleration voltage or a deceleration voltage.

Meanwhile, the ion implantation energy is determined by the sum of the extraction of the source part 300 and the acceleration or deceleration of the ion beam line part 400. Acceleration of the ion implantation energy in the ion beam line unit 400 is called an acceleration mode, and conversely, in the case of decelerating the ion implantation energy, it is called a deceleration mode.

The ion implantation process extracts the ion beam by accelerating to an extraction voltage of 40 kV, for example, to extract the ion beam. After the ion beam is extracted, the ion implanter is typically used in an acceleration mode for a high energy process of 40 kV or more and in a deceleration mode for a low energy process of 30 kV or less. The transition from the acceleration mode to the deceleration mode in the ion implantation process using the ion implantation apparatus uses a device called a swing arm assembly.

In the transition from the acceleration mode to the deceleration mode, as shown in FIG. 2, the deceleration bar 100 of the swing arm assembly contacts the acceleration ring 220 of the acceleration column 200. Let's do it. Then, the deceleration mode is implemented by supplying the deceleration voltage to the acceleration ring 220 through the deceleration voltage output contactor 160 of the deceleration bar 100.

As described above, the deceleration mode uses the principle that the ion beam is decelerated at the portion to which the deceleration voltage from the deceleration bar 100 to the acceleration column 200 is applied. However, when the ion beam is decelerated, ion beam focusing is turned off. If the ion beam is focused and is out of the normal ion beam shape, the ion beam density is biased to either side when ion implantation into the wafer does not result in uniform ion implantation.

Accordingly, a deceleration suppression supply contactor 140 for applying a deceleration suppression voltage to the acceleration column 200 is provided in the deceleration bar 100 so that ion beam focusing may be performed by absorbing scattered ion beams. It is provided. In addition, when the deceleration suppression voltage is applied, the generation of secondary electrons generated by the ion beam colliding with the electrode is suppressed. Here, reference numeral 120 denotes a terminal ground contactor 120. In the deceleration bar 100, the deceleration suppression supply contactor 140 and the deceleration voltage supply contactor 160, including the terminal ground contactor 120, are positioned in the longitudinal direction of the deceleration bar 100. The contactors 120, 140, and 160 are spaced apart from each other to align with the acceleration ring 220 of the acceleration column 200.

On the other hand, the deceleration bar 100 is provided with a deceleration suppression monitor contactor 150 to monitor the deceleration suppression voltage. The deceleration suppression monitor contactor 150 may be simultaneously contacted with a suitable position on the acceleration bar 100, for example, any acceleration ring 220a of the acceleration column 200 contacted with the deceleration suppression supply contactor 140. It is preferable that it is formed in a position adjacent to the deceleration suppression supply contactor 140.

Referring to FIG. 3, the deceleration suppression monitor contactor 150 has, for example, a wire terminal 158 that is an end of the wire 157 at the lower end of the cylindrical body 154 and a contact terminal 152 at the upper end. . The wire terminal 158 is electrically connected to the acceleration column as needed, for example, in the deceleration mode through the contact terminal 152. In addition, a shock absorber 156 such as a spring is installed inside the cylindrical body 154. Other contactors 120, 140, 160 also have the same or similar structure.

2, the deceleration suppression supply contactor 140 and the deceleration suppression monitor contactor 150 provided in the deceleration bar 100 are connected to a deceleration suppression power supply 600. The deceleration suppression voltage contactor 140 is electrically connected to the deceleration suppression power supply unit 600 by a predetermined connection means 610 for supplying the deceleration suppression voltage. Here, the connecting means 610, that is, the supply means 610 (supply menas) includes all means that can be electrically connected, such as wired or wireless. In addition, the deceleration suppression monitor contactor 150 is also electrically connected to the deceleration suppression power supply unit 600 by a predetermined connection means 620 capable of monitoring whether the deceleration suppression voltage is supplied. The connecting means 620, ie the feedback means 62, also includes all means which can be electrically connected, such as wired or wireless.

The ion implantation device configured as described above operates as follows.

Referring back to FIG. 2, when the deceleration voltage is applied to the acceleration ring 220 of the acceleration column 200 via the deceleration voltage supply contactor 160 of the deceleration bar 100, the ion implantation process proceeds in the deceleration mode. The deceleration suppression voltage is also transmitted to the acceleration column 200 via the deceleration suppression supply contactor 140. Then, the phenomenon that the ion beam focusing is distorted and the generation of the secondary electrons are suppressed, so that a uniform ion implantation process is performed on the wafer.

In this case, the deceleration suppression monitor contactor 150 is also preferably contacted simultaneously with the deceleration suppression supply contactor 150 and the acceleration ring 220a that has been contacted. As such, when both the deceleration suppression supply contactor 140 and the deceleration suppression monitor contactor 150 are in contact with the same acceleration ring 220a, the deceleration suppression voltage is correctly applied to the current acceleration column 200 through the feedback means 620. It is easily judged whether or not there is. In detail, when the deceleration suppression voltage is applied to the acceleration column 200 through the supply means 610, it can be seen that the deceleration suppression voltage is normally applied by the feedback means 620.

However, when the deceleration suppression supply contactor 140 has poor contact with a specific acceleration ring 220a and the deceleration suppression monitor contactor 150 has a good contact, the deceleration suppression voltage required for the acceleration column 200 may not be applied smoothly. . However, since the deceleration suppression monitor contactor 150 makes good contact with the specific acceleration ring 220a, it is easy to determine that the deceleration suppression voltage required for the acceleration column 200 is not applied.

On the contrary, when the deceleration suppression supply contactor 140 has good contact with the specific acceleration ring 220a and the deceleration suppression monitor contactor 150 has poor contact, the deceleration suppression voltage required for the acceleration column 200 is continuously stable. It will not be able to read whether it is authorized by. Therefore, the deceleration suppression supply contactor 140 and the deceleration suppression monitor contactor 150 are both already contacted with the same acceleration ring 220a at the same time.

As described above, according to the ion implantation apparatus according to the present invention, since the suppression voltage monitoring contactor is additionally installed in the deceleration bar in addition to the suppression voltage supply contactor, monitoring and feedback of the normal supply of the suppression voltage are possible. It works.

Claims (6)

An end retention portion on which the wafer to be doped is placed; A source unit generating ions of elements to be doped into the wafer; An ion beam line unit including an acceleration column for accelerating or decelerating the generated ions; And And a deceleration bar including a deceleration suppression supply contactor for supplying a deceleration suppression voltage to the acceleration column, and a deceleration suppression monitor contactor capable of monitoring the deceleration suppression voltage. The method of claim 1, And the deceleration suppression supply contactor and the deceleration suppression monitor contactor are simultaneously in contact with the acceleration column. The method of claim 1, And the deceleration suppression supply contactor and the deceleration suppression monitor contactor are electrically connected to the deceleration suppression power supply unit. The method of claim 3, The deceleration suppression supply contactor is electrically connected to the deceleration suppression power supply unit by a supply means, and the deceleration suppression monitor contactor is electrically connected to the deceleration suppression power supply unit by a feedback means. . The method of claim 4, wherein And each one of the supply means and the feedback means is one of a wired means and a wireless means. The method of claim 1, The deceleration bar further includes a terminal ground contactor and a deceleration voltage supply contactor.