TW202100324A - Scan robot for semiconductor wafer ion implantation - Google Patents

Abstract

The present invention relates to a scan robot for semiconductor wafer ion implantation, comprising: an L1 shaft vertically coupled to one side of the first link and driven by a first driving unit to drive the first link to rotate; an L2 shaft, wherein a second link having the same length as the first link is superimposed on the upper part of the first link, vertically coupled to the other side of the first link and to one side of the second link superimposed thereon and driven by a second driving unit to drive the second link to rotate; an R shaft, wherein a support frame for supporting the scan head is superimposed on the other side of the second link, vertically coupled to the other side of the second link and the center of the support frame and driven by a third driving unit to drive the support frame to rotate; and a Y shaft horizontally coupled to the support frame to support both sides of the scan head and driving the scan head to rotate by driving of a fourth driving unit. According to an embodiment of the present invention, a scalar motion capable of scanning in any designated direction in the horizontal direction through the motion of the L1 shaft and the L2 shaft is implemented, and the incident angle of the ion beam is maintained a constant in the left and right scan process through adjusting the motion of the R shaft. It can prevent the beam channeling phenomenon according to the wafer crystal direction through the motion of the S shaft and the shadow phenomenon is prevented, thereby improving the uniformity of ion beam implantation on the wafer. In addition, even when implanting low-energy ions with a high tilt angle, all places on the wafer are irradiated by an equidistant ion beam, which significantly improves the doping uniformity on the wafer, and has the effect of satisfying the doping uniformity requirements of the next generation semiconductor.

Description

Semiconductor wafer ion implantation scanning robot

Invention field

The present invention relates to a semiconductor wafer ion implantation scanning robot. More specifically, the semiconductor wafer ion implantation scanning robot can scan the wafer in any designated direction in the horizontal direction during the ion implantation process of the semiconductor wafer to be implanted on the wafer The ions are uniformly distributed.

Background of the invention

The semiconductor device manufacturing process usually repeats an oxidation process, a photo etching process, a diffusion process, an ion implantation process, and a metal process on the silicon wafer.

The ion implantation process in the manufacturing process refers to implanting impurities charged according to a predetermined energy into the wafer according to the required amount and the required depth. In the semiconductor manufacturing process, the ion implantation process usually refers to implanting dopant ions on the surface of the silicon wafer.

The ion implanter (Ion Implanter) used in the ion implantation process mainly includes the following three parts.

The main part can be divided into: the field of ion source (Ion Source) as the field of extracting ion beam (Ion Beam); including the mass analyzer (Mass Analyzer) that classifies the extracted ion beam according to the required quality and the field of ion beam The terminal area of the beamline of the path; the end-station area where the wafer is transferred and the ion beam is finally implanted.

In the End-Station field, the wafer is scanned and ion beams are injected into the process chamber in a high vacuum state.

Figure 1 is the most representative example of the previous wafer beam scanning method. An air bearing is installed at the lower end of a high-vacuum process chamber and the up and down movement in the mechanism is performed, so as to be relative to the horizontal belt. A parallel ion beam (Parallel Ribbon Beam) or a horizontal scanning ion beam (Parallel Scanned Beam) performs ion implantation in a vertical direction for mechanical scanning (Mechanical Scanning).

The following tilt (Tilt) method is adopted, that is, the process is performed within a certain time after the wafer is tilted to a certain angle with respect to the ion beam according to the types of components to be formed on the wafer. Therefore, the ion implantation process requires the ability to adjust the angle of the ion beam incident on the wafer, and the incident angle is called the tilt angle.

As shown in FIG. 2, in the prior art, the angle of the rotation axis of the wafer holder (Wafer Chuck) that holds the wafer is adjusted to adjust the inclination angle as the incident angle of the ion beam.

However, as shown in Figure 3, the previous tilt angle adjustment method uses High Tilt Angle to implant low-energy ion beams with severe beam bloat-up, and the ion beams reach the upper part of the wafer and the crystal. The distance between the lower part of the circle causes a difference in the ion beam density in the vertical direction of the wafer, which leads to a deterioration in the uniformity of ion beam implantation. This is the same as when the flash is turned on at night, the closer the distance is brighter, and the farther the distance is, the more serious the beam divergence and the darkening will be.

In particular, recently, semiconductor devices have become increasingly denser and their circuit widths have sharply reduced. Therefore, in order to make the doping depth thinner and thinner on the wafer surface, ion implantation using lower energy (Low Energy) is gradually required.

Therefore, it is necessary to develop an ion implantation device that can perform ion implantation with the same ion beam density even when a low-energy ion beam is used at a high tilt angle (Wafer) position. [Prior Technical Literature] (Patent Document 1) Republic of Korea Published Patent No. 10-2000-0024763 (Publication date 2000.05.06) (Patent Document 2) Republic of Korea Published Patent No. 10-2007-0047637 (Publication Date 2007.05.07)

Summary of the invention

The present invention aims to solve the problems of the prior art.

The purpose of the present invention is to provide a semiconductor wafer ion implantation scanning robot, which is installed in a high-vacuum process chamber (Process Chamber) in the field of a terminal station and can scan the wafer in any designated direction in the horizontal direction to make it come from the terminal (Terminal) The ion beam is uniformly injected into the wafer (Wafer).

Another object of the present invention is to provide a unique scanning method of semiconductor wafer ion implantation scanning robot, even during high-inclination low-energy ion implantation, it can improve the crystal by irradiating the entire area on the wafer with equidistant sub-beams. The doping uniformity on the circle, at the same time, can also meet the doping uniformity requirements of the new generation of semiconductors.

In order to achieve the objective, the semiconductor wafer ion implantation scanning robot according to an embodiment of the present invention includes: an L1 axis, which is vertically coupled to one side of the first link, and drives the first link by the driving of the first driving unit Rotation; L2 axis, stack a second link with the same length as the first link on the upper part of the first link, vertically combined on the other side of the first link and stacked on it On one side of the second link on the upper side and driven by the second drive unit to drive the second link to rotate; R axis, on the other side of the second link on the upper part of the support for supporting the scanning head Frame, vertically coupled to the other side of the second link and the center of the support frame and driven by the third drive unit to drive the support frame to rotate; and the Y axis is horizontally coupled to the support frame It supports both sides of the scanning head, and drives the scanning head to rotate by virtue of the driving of the fourth driving unit.

Here, the first drive unit is provided at the lower part of the first link so that the L1 axis is vertically coupled to the first link, and the second drive unit is provided on the other side of the first link. One side of the interior is used to allow the L2 shaft to be vertically coupled to the second link, and the third drive unit is provided inside the other side of the second link to allow the R-axis to be vertically coupled to the In the center of the support frame, the fourth drive unit is arranged on one side of the support frame so that the Y-axis is horizontally coupled to the upper end of the support frame.

Moreover, the first drive unit and the second drive unit are driven synchronously, the first link rotates to the left and right based on the L1 axis, and the second link rotates to the left based on the L2 axis. , Rotate right, so that the scanning head moves horizontally to the left and right.

Furthermore, the third driving unit and the first driving unit are driven synchronously, and the R axis drives the scan head to rotate at the same rotation angle as the L1 axis.

Furthermore, the L1 axis is driven to rotate to adjust the inclination angle, the driving of the first drive unit and the second drive unit are synchronized under the adjusted inclination angle, and the first link is moved on the basis of the L1 axis. Rotate left and right, and rotate the second link to the left and right based on the L2 axis, so that the scanning head moves horizontally to the left and right.

Moreover, the third driving unit drives in synchronization with the first driving unit under the adjusted inclination angle, and the R axis drives the scan head to rotate at the same rotation angle as the L1 axis.

The Y axis drives the wafer of the scan head to rotate to a wafer loading or unloading position or drives the wafer of the scan head to rotate to an ion implantation position or a beam profiling position.

Moreover, the scanning head includes a wafer holder for fixing the wafer, an S axis for driving the wafer holder to rotate, and a fifth drive unit for driving the S axis, the S axis is perpendicular to the Y axis, The wafer holder on which the wafer is placed is driven to rotate to adjust the twist angle (Twist Angle) or the orientation angle (Orientation Angle) of the wafer.

According to the embodiment of the present invention, the scalar motion that can be scanned in any specified direction in the horizontal direction is realized through the actions of the L1 axis and the L2 axis, and the R axis action is adjusted to keep the ion beam constant during the left and right scans. The incident angle of the S-axis can prevent the beam channel effect and prevent the shadow phenomenon according to the crystal direction of the wafer, thereby improving the uniformity of ion beam implantation on the wafer.

Moreover, during high-inclination low-energy ion implantation, the entire area on the wafer can be irradiated by equidistant sub-beams to greatly improve the uniformity of doping on the wafer. At the same time, it can also meet the doping of the new generation of semiconductors. Impurity uniformity requires conditions.

Detailed description of the preferred embodiment

The following detailed description of the present invention is a practical embodiment of the present invention, and reference is made to the drawing as an example of the embodiment in the description. In order to enable those skilled in the art of the present invention to implement the present invention, these embodiments will be described in great detail below. Although the various embodiments of the present invention are different from each other, they should be interpreted as not necessarily mutually exclusive. For example, the specific shape, structure, and characteristics of an embodiment described can be implemented in another embodiment without departing from the spirit and scope of the present invention. Moreover, the individual positions or configurations in the disclosed embodiments should be interpreted as being able to be modified without departing from the spirit and scope of the present invention.

Therefore, the following detailed description should not be regarded as restrictive. As long as it can be properly described, the scope of the present invention can only be given by all equivalent ranges equivalent to the requested content of its patent application and the attached patent application scope. limited. Similar symbols in the drawings indicate the same or similar functions in all aspects.

The terminology used in the present invention has considered its functions in the present invention and has chosen general terms that are currently widely used as much as possible, but may vary according to factors such as the intention or practice of those skilled in the art or the emergence of new technologies. Changed. Moreover, in certain circumstances, the term arbitrarily selected by the applicant is also used, and its meaning will be described in detail in the corresponding invention content. Therefore, the terms used in the present invention cannot be defined solely by the term name, but should be defined according to the meaning of the term and the overall content of the present invention.

Throughout this specification, when it is said that a certain part "includes" a certain component, it means that, unless the contrary content is specifically stated, it does not exclude other components but can also include other components.

Moreover, the terms "...unit" and "...module" described in the specification refer to a unit that processes at least one function or action, which can be implemented by hardware or software, or through a combination of hardware and software. achieve.

As shown in FIGS. 4 and 5, for a vertical ribbon beam (Vertical Ribbon Beam) or a vertical scanning ion beam (Vertical Scanning), the semiconductor wafer ion implantation scanning robot according to an embodiment of the present invention passes through the L1 axis and the L2 axis. The actions of the 5 drive shafts composed of, R-axis, Y-axis, and S-axis perform left and right mechanical scanning in all directions in the horizontal plane.

First, as shown in FIG. 5, a first drive unit 110 is provided at the lower part of one side of the first link 100. The L1 shaft 120, which is the drive shaft of the first drive unit 110, is vertically combined with one of the first link 100. side. The L1 axis 120 becomes the reference axis of the scanning robot, and the first link 100 is driven to rotate left and right by the driving of the first driving unit 110.

Furthermore, a second link 200 having the same length as the first link 100 is stacked on the upper part of the first link 100.

A second drive unit 210 is provided inside the other side of the first link 100, and an L2 shaft 220 as a drive shaft of the second drive unit protrudes from the upper portion and is vertically coupled to one side of the second link 200. The L2 shaft 220 drives the second link 200 to rotate left and right by the driving of the second driving unit 210.

Moreover, a support 300 supporting the scanning head 400 is stacked on the upper part of the other side of the second link 200.

A third driving unit 310 is provided inside the other side of the second link 200, and an R shaft 320 as a driving shaft of the third driving unit 310 protrudes from the upper part and is vertically combined in the center of the support frame 300. The R shaft 320 drives the support frame 300 to rotate left and right by the driving of the third driving unit 310.

Here, the first driving unit 110, the second driving unit 210, and the third driving unit 310 are synchronized and driven.

As shown in Figure 6 (a) and (b), if it is a 0° scan, in the initial state of Figure 6 (a), as shown in Figure 6 (b), the first link 100 is in the first drive unit When the 110 is driven, it rotates based on the L1 shaft 120, and the second link 200 having the same length as the first link rotates on the L2 shaft 220 when driven by the second drive unit 210 synchronized with the first drive unit. The scanning head 400 is driven to move horizontally to the left and right.

6(b), the first link 100 rotates to the left based on the L1 axis 120 due to the driving of the first drive unit 110. At the same time, the second link 200 is driven by the first drive unit 110. The synchronized driving of the second drive unit 210 rotates to the left based on the L2 shaft 220, and then the first link 100 rotates to the right based on the L1 shaft 120 due to the driving of the first drive unit 110, and at the same time, Due to the driving of the second driving unit 210 synchronized with the first driving unit, the second link 200 rotates to the right based on the L2 axis 220, so that the scanning head 400 moves horizontally to the left and right. At the same time, the scan head 400 rotates to the left and right based on the R axis 320 due to the driving of the third driving unit 310 synchronized with the first driving unit 110. At this time, the R-axis 320 performs an adjustment function during the left and right scanning processes so that the ion beam maintains a certain incident angle.

That is, the scanning head 400 realizes a scalar movement capable of scanning in any designated direction of the horizontal direction by rotating the L1 axis 120, the L2 axis 220, and the R axis 320 at the same time.

Furthermore, as shown in (a) and (b) of FIG. 7, in the 45° tilt scan, as shown in FIG. 7 (a), the reference L1 axis 120 is rotated by 45° in the initial state of 0°. At this time, if the L1 shaft 120 is rotated by 45° by the driving of the first driving unit 110, the first link 100, the second link 200, and the scanning head 400 are rotated by an angle of 45°. Furthermore, the scanning head 400 is moved horizontally to the left and right as shown in FIG. 7(b) with the scanning head 400 inclined at 45°. Here, the left and right horizontal movement of the scan head 400 is realized in the same manner as described in FIG. 6(b).

That is, the scanning head 400 realizes a scalar movement capable of scanning in any designated direction in the horizontal direction when it is inclined at 45°.

On the other hand, the scan head 400 supported by the supporting frame 300 is joined to the horizontally coupled Y-axis 420.

As shown in Figure 5, one side of the support frame 300 is provided with a fourth drive unit 410, and the Y axis 420 as the drive shaft of the fourth drive unit 410 is horizontally combined with the support frame 300 and supports both sides of the scan head 400, The driving of the fourth driving unit 410 drives the scan head 400 to rotate.

As shown in (a) and (b) of FIG. 8, the Y-axis 420 that is rotated by the driving of the fourth drive unit 410 plays a role in driving the scanning head 400 to rotate to the wafer loading or unloading position or driving the crystal placed in the scanning head. The function of rotating the wafer of the circular holder to the ion implantation position or the beam profiling position.

As shown in (a) of FIG. 9, the scanning head 400 includes a wafer holder 401 for fixing a wafer, an S-axis 402 for driving the wafer holder 401 to rotate, and a fifth driving unit 403 for driving the S-axis 402.

Moreover, as shown in FIG. 9(b), the S axis 402 is perpendicular to the Y axis 420, and the wafer holder 401 on which the wafer is placed is rotated by the fifth drive unit 403 to adjust the wafer ( Wafer's twist angle (Twist Angle) or azimuth angle (Orientation Angle).

Here, the first reason why Tilt Angle and Twist Angle need to be adjusted during ion implantation is to prevent the beam channeling effect caused by the crystal orientation of the semiconductor and the beam incident angle needs to be adjusted to The second reason for the difficult crystal orientation of the channel effect is that in order to prevent the shadow phenomenon that occurs in the recent oblique ion implantation of a semiconductor with a three-dimensional structure, it is necessary to perform ion implantation at various angles.

Therefore, the present invention realizes scalar motion that can scan in any designated direction in the horizontal direction through the actions of the L1 axis 120 and the L2 axis 220, and adjusts through the action of the R axis 320 to keep the ion beam constant during the left and right scans. The incident angle of φ, through the action of the S-axis 402 can prevent the beam channel effect and prevent the shadow phenomenon according to the crystal direction of the wafer, thereby improving the uniformity of ion beam implantation on the wafer.

FIG. 10 is a top view illustrating the uniformity of doping when the semiconductor wafer ion implantation scanning robot performs large-angle and inclined ion implantation of the wafer according to an embodiment of the present invention.

As shown in FIG. 10, the semiconductor wafer ion implantation scanning robot scans the wafer with uniform ion beam density at all positions on the wafer during 0° Tilt Implantation (0° Tilt Implantation).

At the same time, even if tilted at a large angle, the vertical ribbon ion beam or the vertical scanning ion beam will be scanned from left to right on the wafer. Therefore, there is no difference in the beam path regardless of the tilt angle. Therefore, the wafer scanning During the process, the beam uniformity is maintained constant, so that ions can be injected uniformly at all positions on the wafer.

As mentioned above, the present invention can scan the wafer in any designated direction in the horizontal direction so that the ion beam can be uniformly implanted on the wafer (Wafer), even during the high-inclination low-energy ion implantation, the wafer can be The whole area is irradiated by equidistant sub-beams to greatly improve the uniformity of doping on the wafer.

Moreover, it solves the problem of doping uniformity caused by the distance difference of the ion beam path of each wafer position in the scanning direction in the prior art and the resultant ion beam size change. At the same time, it can also meet the new generation semiconductor The uniformity of doping requires conditions.

The foregoing describes the preferred embodiments of the present invention, but the present invention is not limited to the specific embodiments. That is, those with general knowledge in the technical field to which the present invention belongs can make various variations and modifications to the present invention without departing from the spirit and scope of the claims. All these appropriate variations and modifications shall be interpreted as equivalents as belonging to the present invention. The scope of the invention.

100: first link 110: The first drive unit 120: L1 axis 200: second link 210: second drive unit 220: L2 axis 300: support frame 310: Third drive unit 320: R axis 400: Scan head 401: Wafer holder 402: S axis 403: Fifth drive unit 410: fourth drive unit 420: Y axis L1, L2, R, Y: axis

FIG. 1 is a conceptual diagram showing a conventional wafer beam scanning method. FIG. 2 is a conceptual diagram showing the tilt angle adjustment operation in the conventional wafer beam scanning method shown in FIG. 1. FIG. 3 is a side view for explaining the problem of large-angle oblique ion implantation of the wafer in the conventional wafer beam scanning method shown in FIG. 1 and FIG. 2. 4 is a conceptual diagram showing a wafer beam scanning method of a semiconductor wafer ion implantation scanning robot according to an embodiment of the present invention. 5 is a schematic diagram illustrating the structure of a semiconductor wafer ion implantation scanning robot according to an embodiment of the present invention. Fig. 6 (a) and (b) illustrate the operation of the L1 axis, L2 axis, and R axis of the semiconductor wafer ion implantation scanning robot according to an embodiment of the present invention. Figure. 7(a) and (b) are operation diagrams illustrating the 45° tilt scanning operation of the semiconductor wafer ion implantation scanning robot according to an embodiment of the present invention. FIGS. 8(a) and (b) are operation diagrams illustrating the operation of the scan head based on Y-axis driving in the semiconductor wafer ion implantation scan robot according to an embodiment of the present invention. Figure 9 (a) and (b) illustrate the adjustment of wafer twist angle (Twist Angle) or orientation angle (Orientation Angle) adjustment by means of the S-axis drive of the scan head in the semiconductor wafer ion implantation scanning robot of an embodiment of the present invention Action figure. FIG. 10 is a top view illustrating the uniformity of doping when the semiconductor wafer ion implantation scanning robot performs large-angle and inclined ion implantation of the wafer according to an embodiment of the present invention.

L1, L2, R, Y: axis

Claims (9)

A semiconductor wafer ion implantation scanning robot, in which, include: The L1 axis is vertically coupled to one side of the first connecting rod, and the first connecting rod is driven to rotate by the driving of the first driving unit; L2 axis, stack a second link with the same length as the first link on the upper part of the first link, vertically connected to the other side of the first link and stacked on it One side of the second connecting rod drives the second connecting rod to rotate by virtue of the driving of the second driving unit; The R axis is stacked on the upper part of the other side of the second link to support the support frame of the scanning head, which is vertically combined on the other side of the second link and the center of the support frame and is driven by the third The drive of the unit drives the support frame to rotate; and The Y axis is horizontally combined with the support frame and supports both sides of the scan head, and drives the scan head to rotate by the driving of the fourth driving unit. The semiconductor wafer ion implantation scanning robot according to claim 1, wherein: The first drive unit is provided at the lower part of the first link so that the L1 axis is vertically coupled to the first link, and the second drive unit is provided inside the other side of the first link In order to allow the L2 axis to be vertically coupled to the second link, the third drive unit is arranged inside the other side of the second link so that the R axis is vertically coupled to the support frame In the center of the support frame, the fourth driving unit is arranged on one side of the support frame so that the Y-axis is horizontally coupled to the upper end of the support frame. The semiconductor wafer ion implantation scanning robot according to claim 1, wherein: The first drive unit and the second drive unit are driven synchronously, the first link rotates to the left and right based on the L1 axis, and the second link rotates to the left and right based on the L2 axis Rotate, so that the scanning head moves horizontally to the left and right. The semiconductor wafer ion implantation scanning robot according to claim 3, wherein: The third driving unit and the first driving unit are driven synchronously, and the R axis drives the scan head to rotate at the same rotation angle as the L1 axis. The semiconductor wafer ion implantation scanning robot according to claim 1, wherein: Drive the L1 axis to rotate to adjust the inclination angle, synchronize the driving of the first drive unit and the second drive unit under the adjusted inclination angle, and use the L1 axis as a reference to make the first link to the left, Rotate to the right, and rotate the second link to the left and right based on the L2 axis, so that the scanning head moves horizontally to the left and right. The semiconductor wafer ion implantation scanning robot according to claim 5, wherein: The third driving unit drives in synchronization with the first driving unit under the adjusted inclination angle, and the R axis drives the scan head to rotate at the same rotation angle as the L1 axis. The semiconductor wafer ion implantation scanning robot according to claim 1, wherein: The Y axis drives the wafer of the scan head to rotate to a wafer loading or unloading position or drives the wafer of the scan head to rotate to an ion implantation position or a beam profile analysis position. The semiconductor wafer ion implantation scanning robot according to claim 1, wherein: The scan head includes a wafer holder for fixing a wafer, an S axis for driving the wafer holder to rotate, and a fifth driving unit for driving the S axis. The semiconductor wafer ion implantation scanning robot according to claim 8, wherein: The S-axis is perpendicular to the Y-axis to drive the wafer holder on which the wafer is placed to rotate to adjust the twist angle (Twist Angle) or the orientation angle (Orientation Angle) of the wafer.

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