CN109860012B

CN109860012B - Vertical scanning device of ion implanter

Info

Publication number: CN109860012B
Application number: CN201910151233.4A
Authority: CN
Inventors: 袁卫华; 彭立波; 程文进; 许波涛; 徐松; 王迪平; 周波
Original assignee: CETC 48 Research Institute
Current assignee: CETC 48 Research Institute
Priority date: 2019-02-28
Filing date: 2019-02-28
Publication date: 2021-02-05
Anticipated expiration: 2039-02-28
Also published as: CN109860012A

Abstract

The invention discloses a vertical scanning device of an ion implanter, which comprises a vacuum chamber and a target table positioned in the vacuum chamber, wherein the vertical scanning device comprises a bracket, a main shaft, a first driving mechanism for driving the main shaft to lift and a second driving mechanism for driving the main shaft to rotate, the vacuum chamber is arranged on the bracket, the upper end of the main shaft is connected with the target table, and the lower end of the main shaft extends out of the vacuum chamber and is connected with the first driving mechanism and the second driving mechanism. The invention has the advantages of reducing the space occupied by the vacuum process chamber, avoiding influencing the ultimate vacuum degree of the process chamber and the like.

Description

Vertical scanning device of ion implanter

Technical Field

The present disclosure relates to ion implanters, and particularly to a vertical scanning device for an ion implanter.

Background

Ion implanters are one of the key pieces of equipment in semiconductor processing. In order to ensure the uniformity of the ion implantation dose, the ion implantation equipment usually needs to adopt a certain scanning mode. As the size of silicon wafers is getting larger and the requirements of ion implantation processes are getting higher, the early batch type target plate is difficult to meet new process requirements, and the single-wafer implantation target platform gradually becomes the mainstream of the current ion implanter. In this type of implanter system, the general requirements are: the ion beam is corrected by electric scanning, an electromagnet and the like in the horizontal direction, and is finally diverged in parallel when reaching the target platform, namely the ion beam is kept stable and unchanged in the horizontal direction, then the target platform is made to reciprocate up and down through a scanning device to realize vertical scanning, and meanwhile, the adjustment of the ion implantation angle is realized through the inclined motion of the target platform.

The applicant's granted patent CN 104409307B discloses a scanning device and a scanning method for an ion implanter, which can realize a vertical scanning movement by a relatively simple moving mechanism, and can realize a relatively precise implantation angle control by rotating a target table around a scanning axis by a horizontal rotating mechanism to correct an angle. The vacuum process chamber has the defects that most of a lead screw, a guide rail pair, a driving part and the like in the movement mechanism are positioned in the vacuum process chamber, so that the volume of the vacuum process chamber is overlarge, the lead screw, the guide rail pair and the like need to be lubricated, and the limit vacuum degree in the process chamber can be greatly influenced by oil and grease used for lubricating. In addition, the method for realizing vacuum isolation by the magnetic fluid seal and the linear motor air-entrapping floating bearing has the defects of complex structure, high cost, need of regular maintenance and the like.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide the vertical scanning device of the ion implanter, which can reduce the space occupied by a vacuum process chamber and avoid influencing the ultimate vacuum degree of the process chamber.

In order to solve the technical problems, the invention adopts the following technical scheme:

the utility model provides an ion implantation machine vertical scanning device, ion implantation machine include the vacuum chamber and be located the target table in the vacuum chamber, and vertical scanning device includes support, main shaft, be used for driving the first actuating mechanism of main shaft lift and be used for driving the rotatory second actuating mechanism of main shaft, the vacuum chamber is located on the support, the main shaft upper end with the target table links to each other, and the main shaft lower extreme extends to outside the vacuum chamber, and with first actuating mechanism and second actuating mechanism link to each other.

As a further improvement of the above technical solution: the utility model discloses a sealing structure, including main shaft, seal seat, first sealing washer, second sealing washer and third sealing washer, be equipped with first sealed spacer between first sealing washer and the second sealing washer in proper order, be equipped with the sealed spacer of second between second sealing washer and the third sealing washer, first sealed spacer and the sealed spacer of second all with the space has between the main shaft, be equipped with the first evacuation passageway with downside space intercommunication on the first sealed spacer, be equipped with the second evacuation passageway with upside space intercommunication on the sealed spacer of second, atmospheric pressure in the upside space is less than the atmospheric pressure in the downside space.

As a further improvement of the above technical solution: the support with be connected with between the seal receptacle and be used for preventing the main shaft is along the supporting component of radial skew, the supporting component includes that a pair of branch locates the first limit guide rail of main shaft both sides and a pair of branch locate the second limit guide rail of main shaft both sides, first limit guide rail with the second limit guide rail is arranged perpendicularly.

As a further improvement of the above technical solution: the support upper portion is equipped with flange, main shaft periphery cover is equipped with the ripple sealed tube, ripple sealed tube upper end with flange welding, the lower extreme with the seal receptacle welding.

As a further improvement of the above technical solution: the first sealing ring, the second sealing ring and the third sealing ring are lip-shaped sealing rings, and the first sealing spacer bush and the second sealing spacer bush are polytetrafluoroethylene sealing spacer bushes.

As a further improvement of the above technical solution: the first driving mechanism comprises a first motor reducer, a first driving belt wheel assembly, a lead screw and a nut seat arranged on the lead screw, the first motor reducer and the lead screw are arranged on the support, the first driving belt wheel assembly is connected between the first motor reducer and the lead screw, the second driving mechanism is arranged on the nut seat, and the lower end of the main shaft is rotatably arranged in the nut seat in a penetrating mode.

As a further improvement of the above technical solution: the second driving mechanism comprises a second motor reducer and a second transmission belt wheel assembly, the second motor reducer is arranged on the nut seat, and the second transmission belt wheel assembly is connected between the second motor reducer and the main shaft.

As a further improvement of the above technical solution: lifting guide rails are arranged on the two sides of the lead screw on the support, and the nut seat is provided with a sliding block matched with the lifting guide rails.

Compared with the prior art, the invention has the advantages that: the invention discloses a vertical scanning device of an ion implanter, which is supported by a bracket, wherein a first driving mechanism drives a main shaft and a target table to reciprocate up and down to realize vertical scanning, and a second driving mechanism drives the main shaft and the target table to rotate horizontally to realize injection angle control; the first driving mechanism and the second driving mechanism are arranged at the lower end of the main shaft, namely outside the vacuum chamber, and only the upper end of the main shaft extends into the vacuum chamber, so that the space occupied by the kinematic pair in the vacuum chamber is reduced, and the phenomenon that grease used for lubricating the kinematic pair influences the ultimate vacuum degree in the vacuum chamber is avoided.

Drawings

Fig. 1 is a schematic structural diagram of a vertical scanning device of an ion implanter according to the present invention.

Fig. 2 is a schematic cross-sectional view of a vertical scanning device of an ion implanter according to the present invention.

Fig. 3 is a perspective view of the stent of the present invention.

Fig. 4 is a front view schematically showing the structure of the stand according to the present invention.

Fig. 5 is an enlarged perspective view of the support assembly of the present invention.

The reference numerals in the figures denote: 1. a vacuum chamber; 2. a target platform; 3. a support; 31. a support assembly; 311. a first limit guide rail; 312. a second limit guide rail; 32. a connecting flange; 33. a lifting guide rail; 4. a main shaft; 41. a first seal ring; 42. a second seal ring; 43. a third seal ring; 44. a first seal spacer; 45. a second seal spacer; 46. a first evacuation channel; 47. a second evacuation channel; 48. a corrugated sealing tube; 5. a first drive mechanism; 51. a first motor reducer; 52. a first drive pulley assembly; 53. a lead screw; 54. a nut seat; 55. a slider; 6. a second drive mechanism; 61. a second motor reducer; 62. a second drive pulley assembly; 7. and (4) a sealing seat.

Detailed Description

The invention is described in further detail below with reference to the figures and specific examples of the specification.

Fig. 1 to 5 show an embodiment of a vertical scanning device of an ion implanter according to the present invention, the ion implanter includes a vacuum chamber 1 and a target table 2 located in the vacuum chamber 1, the vertical scanning device includes a support 3, a spindle 4, a first driving mechanism 5 for driving the spindle 4 to ascend and descend, and a second driving mechanism 6 for driving the spindle 4 to rotate, the vacuum chamber 1 is disposed on the support 3, an upper end of the spindle 4 is connected to the target table 2, and a lower end of the spindle 4 extends out of the vacuum chamber 1 and is connected to the first driving mechanism 5 and the second driving mechanism 6.

The vertical scanning device of the ion implanter is supported by a bracket 3, a first driving mechanism 5 drives a main shaft 4 and a target table 2 to reciprocate up and down to realize vertical scanning, and a second driving mechanism 6 drives the main shaft 4 and the target table 2 to rotate horizontally to realize implantation angle control; the first driving mechanism 5 and the second driving mechanism 6 are arranged at the lower end of the main shaft 4, namely the outside of the vacuum chamber 1, only the upper end of the main shaft 4 extends into the vacuum chamber 1, so that the space occupied by the kinematic pair in the vacuum chamber 1 is reduced, and the grease used for lubricating the kinematic pair is prevented from influencing the ultimate vacuum degree in the vacuum chamber 1.

Further, in this embodiment, the upper end of the main shaft 4 is inserted into a sealing seat 7, a first sealing ring 41, a second sealing ring 42 and a third sealing ring 43 are sequentially arranged between the sealing seat 7 and the main shaft 4 from bottom to top, a first sealing spacer 44 is arranged between the first sealing ring 41 and the second sealing ring 42, a second sealing spacer 45 is arranged between the second sealing ring 42 and the third sealing ring 43, gaps are formed between the first sealing spacer 44 and the main shaft 4 and between the second sealing spacer 45 and the main shaft 4, a first vacuum pumping channel 46 communicated with the lower gap is arranged on the first sealing spacer 44, a second vacuum pumping channel 47 communicated with the upper gap is arranged on the second sealing spacer 45, and the air pressure in the upper gap is lower than the air pressure in the lower gap. The main shaft 4 is sequentially provided with an atmospheric region, a high negative pressure region, a near low vacuum region and a low vacuum region from bottom to top, a small amount of gas in the atmosphere can be brought when the main shaft 4 moves upwards, the part of the gas is pumped away through the first vacuumizing channel 46, the part which is not pumped away when the main shaft 4 continues to move upwards is pumped away through the second vacuumizing channel 47, and the gas cannot enter the vacuum chamber 1 because the gas is removed step by step, so that the sealing function is achieved, and the vacuum chamber 1 cannot be greatly influenced; meanwhile, as the first sealing spacer 44 and the second sealing spacer 45 are respectively provided with a gap (preferably smaller than 20um) with the main shaft 4, the friction resistance of the main shaft 4 during movement can be reduced, and compared with the existing magnetic fluid seal, linear motor and air bearing and the like, the structure is simpler, the cost is lower, and the daily maintenance is convenient.

Furthermore, in the present embodiment, a supporting assembly 31 for preventing the spindle 4 from deviating in the radial direction is connected between the bracket 3 and the sealing seat 7, the supporting assembly 31 includes a pair of first position-limiting guide rails 311 respectively disposed on two sides of the spindle 4 and a pair of second position-limiting guide rails 312 respectively disposed on two sides of the spindle 4, and the first position-limiting guide rails 311 and the second position-limiting guide rails 312 are vertically disposed. By limiting the radial sliding of the main shaft 4 through the supporting component 31, the sealing leakage can be effectively avoided.

Furthermore, in this embodiment, the upper portion of the bracket 3 is provided with a connecting flange 32, the outer periphery of the main shaft 4 is sleeved with a corrugated sealing pipe 48, the upper end of the corrugated sealing pipe 48 is welded with the connecting flange 32, and the lower end is welded with the sealing seat 7. The sealing of the periphery of the main shaft 4 between the sealing seat 7 and the connecting flange 32 is realized by welding the corrugated sealing pipe 48, and the structure is simple and reliable, and the sealing performance is good.

In the present embodiment, the first seal ring 41, the second seal ring 42, and the third seal ring 43 are lip-shaped seal rings, and the first seal spacer 44 and the second seal spacer 45 are polytetrafluoroethylene seal spacers. The lip-shaped sealing ring has good sealing performance and high reliability; the polytetrafluoroethylene sealing spacer sleeve has good wear resistance and self-lubricating property.

Further, in the present embodiment, the first driving mechanism 5 includes a first motor reducer 51, a first driving pulley assembly 52, a lead screw 53, and a nut seat 54 disposed on the lead screw 53, the first motor reducer 51 and the lead screw 53 are disposed on the bracket 3, the first driving pulley assembly 52 is connected between the first motor reducer 51 and the lead screw 53, the second driving mechanism 6 is disposed on the nut seat 54, and the lower end of the main shaft 4 is rotatably disposed in the nut seat 54 (for example, the main shaft 4 and the nut seat 54 are relatively rotated by a bearing assembly). During operation, the first motor reducer 51 drives the screw 53 to rotate through the first driving pulley assembly 52, and further drives the nut seat 54, the second driving mechanism 6, the spindle 4, and the target table 2 to integrally lift.

Further, in the present embodiment, the second driving mechanism 6 includes a second motor reducer 61 and a second pulley assembly 62, the second motor reducer 61 is disposed on the nut base 54, and the second pulley assembly 62 is connected between the second motor reducer 61 and the main shaft 4. During operation, the second motor reducer 61 drives the spindle 4 and the target table 2 to rotate relative to the nut seat 54 through the second driving pulley assembly 62.

Furthermore, in this embodiment, the lifting guide rails 33 are disposed on the bracket 3 on both sides of the lead screw 53, and the nut base 54 is disposed on the sliding block 55 engaged with the lifting guide rails 33. Through the cooperation of the lifting guide rail 33 and the sliding block 55, the main shaft 4 is ensured to be lifted stably and smoothly, and the vertical deviation is avoided.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make numerous possible variations and modifications to the present invention, or modify equivalent embodiments to equivalent variations, without departing from the scope of the invention, using the teachings disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention should fall within the protection scope of the technical scheme of the present invention, unless the technical spirit of the present invention departs from the content of the technical scheme of the present invention.

Claims

1. The utility model provides an ion implantation machine vertical scanning device, ion implantation machine include vacuum chamber (1) and be located target table (2) in vacuum chamber (1), and vertical scanning device includes support (3), main shaft (4), be used for driving main shaft (4) first actuating mechanism (5) that go up and down, and be used for driving the rotatory second actuating mechanism (6) of main shaft (4), its characterized in that: the vacuum chamber (1) is arranged on the support (3), the upper end of the main shaft (4) is connected with the target table (2), the lower end of the main shaft (4) extends out of the vacuum chamber (1) and is connected with the first driving mechanism (5) and the second driving mechanism (6), the upper end of the main shaft (4) is arranged in a sealing seat (7) in a penetrating way, a first sealing ring (41), a second sealing ring (42) and a third sealing ring (43) are sequentially arranged between the sealing seat (7) and the main shaft (4) from bottom to top, a first sealing spacer sleeve (44) is arranged between the first sealing ring (41) and the second sealing ring (42), a second sealing spacer sleeve (45) is arranged between the second sealing ring (42) and the third sealing ring (43), and a gap is reserved between the first sealing spacer sleeve (44) and the second sealing spacer sleeve (45) and the main shaft (4), the first sealed spacer sleeve (44) is provided with a first vacuumizing channel (46) communicated with the lower side gap, the second sealed spacer sleeve (45) is provided with a second vacuumizing channel (47) communicated with the upper side gap, and the air pressure in the upper side gap is lower than that in the lower side gap.

2. The vertical scanning apparatus of claim 1, wherein: the supporting assembly (31) used for preventing the main shaft (4) from radially deviating is connected between the support (3) and the sealing seat (7), the supporting assembly (31) comprises a pair of first limiting guide rails (311) which are arranged on two sides of the main shaft (4) and a pair of second limiting guide rails (312) which are arranged on two sides of the main shaft (4), and the first limiting guide rails (311) and the second limiting guide rails (312) are vertically arranged.

3. The vertical scanning apparatus of claim 2, wherein: support (3) upper portion is equipped with flange (32), main shaft (4) periphery cover is equipped with ripple sealed tube (48), ripple sealed tube (48) upper end with flange (32) welding, the lower extreme with seal receptacle (7) welding.

4. The vertical scanning apparatus of an ion implanter according to any of claims 1 to 3, wherein: first sealing washer (41), second sealing washer (42) and third sealing washer (43) are lip seal, first sealed spacer (44) and second sealed spacer (45) are polytetrafluoroethylene sealed spacer.

5. The vertical scanning apparatus of an ion implanter according to any of claims 1 to 3, wherein: the first driving mechanism (5) comprises a first motor speed reducer (51), a first driving belt wheel assembly (52), a lead screw (53) and a nut seat (54) arranged on the lead screw (53), the first motor speed reducer (51) and the lead screw (53) are arranged on the support (3), the first driving belt wheel assembly (52) is connected between the first motor speed reducer (51) and the lead screw (53), the second driving mechanism (6) is arranged on the nut seat (54), and the lower end of the main shaft (4) is rotatably arranged in the nut seat (54).

6. The vertical scanning apparatus of claim 5, wherein: the second driving mechanism (6) comprises a second motor reducer (61) and a second transmission pulley assembly (62), the second motor reducer (61) is arranged on the nut seat (54), and the second transmission pulley assembly (62) is connected between the second motor reducer (61) and the main shaft (4).

7. The vertical scanning apparatus of claim 5, wherein: lifting guide rails (33) are arranged on the support (3) on two sides of the lead screw (53), and a sliding block (55) matched with the lifting guide rails (33) is arranged on the nut seat (54).