LOAD LOCK FOR A SUBSTRATE CONTAINER AND DEVICE HAVING SUCH A LOAD LOCK

Abstract

A load lock for a substrate container for receiving flat substrates, wherein the load lock has a load chamber for receiving the substrate container that has a bottom, a ceiling, a rear wall, a front wall, a first side wall and a second side wall that connect the rear wall to the front wall, and wherein a carrier unit for receiving the substrate container is arranged in the load chamber. Here, it is provided that the load chamber can be divided into a first part and a second part along a dividing plane to open the load chamber, wherein the dividing plane extends toward the rear wall offset from the front wall through the first side wall, the second side wall, the bottom and the ceiling of the load chamber.

Claims

1-16. (canceled)

17. A load lock for a substrate container comprising: a housing that has a bottom, a ceiling as well as side walls and being intended for receiving flat substrates, wherein the load lock has a load chamber for receiving the substrate container that has a bottom, a ceiling, a rear wall, a front wall, a first side wall and a second side wall that connect the rear wall to the front wall and wherein a carrier unit for receiving the substrate container is arranged in the load chamber, wherein the load chamber can be divided into a first part and a second part along a dividing plane to open the load chamber, wherein the dividing plane extends toward the rear wall offset from the front wall through the first side wall, the second side wall, the bottom and the ceiling of the load chamber.

18. The load lock according to claim 17, wherein the load chamber in a closed state is sealed against the environment, wherein the load lock has pressure adjusting means for adjusting the pressure in the load chamber.

19. The load lock according to claim 17, wherein it has a lifting unit for lifting and lowering the carrier unit.

20. The load lock according to claim 19, wherein the carrier unit has a slide guided by a guide means.

21. The load lock according to claim 20, wherein the guide means is arranged on the rear wall of the load chamber.

22. The load lock according to claim 21, wherein a bushing for the lifting unit for lifting and lowering the carrier unit is arranged in the bottom of the load chamber.

23. The load lock according to claim 17, wherein a lock opening for transferring a substrate out of or into the load chamber is formed in the rear wall of the load chamber, wherein the lock opening can be closed by means of a lock valve.

24. The load lock according to claim 17, wherein it has an opening mechanism for taking off and putting on the substrate container lid.

25. The load lock according to claim 24, wherein the opening mechanism is arranged above or below the lock opening.

26. The load lock according to claim 19, wherein the lifting unit is a lifting unit for lifting or lowering the carrier unit to at least one of the following positions: an opening and closing position where the upper surface of the carrier unit is in a position that enables the opening mechanism to take off or put on the substrate container lid of a substrate container that is on the upper surface of the carrier unit; and a transfer position where the upper surface of the carrier unit is in a position that enables transfer of a substrate out of or into a substrate container that is on the upper surface of the carrier unit.

27. The load lock according to claim 17, wherein it has an identification system for identifying substrates that are present in the substrate container.

28. The load lock according to claim 27, wherein the identification system is arranged on the rear wall of the load chamber.

29. The load lock according to claim 26, wherein the lifting unit is a lifting unit for lifting or lowering the carrier unit to an identification position, wherein in the identification position the upper surface of the carrier unit is in a position where the identification system can identify a substrate in a substrate container that is present on the upper surface of the carrier unit.

30. A device for processing flat substrates comprising: a process chamber for processing one or more flat substrates; a load lock having a housing that has a bottom, a ceiling as well as side walls and being intended for receiving flat substrates, wherein the load lock has a load chamber for receiving the substrate container that has a bottom, a ceiling, a rear wall, a front wall, a first side wall and a second side wall that connect the rear wall to the front wall and wherein a carrier unit for receiving the substrate container is arranged in the load chamber, wherein the load chamber can be divided into a first part and a second part along a dividing plane to open the load chamber, wherein the dividing plane extends toward the rear wall offset from the front wall through the first side wall, the second side wall, the bottom and the ceiling of the load chamber; and a handling system for transferring one or more substrates between a substrate container received by the carrier unit and the process chamber through the lock opening of the load chamber.

31. A method for operating a load lock comprising the steps of: (a) opening a load chamber by dividing it into the first and the second part; (b) putting a substrate container onto the carrier unit; (c) closing the load chamber by joining the first and the second part; (d) taking off the lid from the substrate container by means of an opening mechanism; and (e) taking out at least one substrate of the substrate container; wherein for carrying out steps (d) and (e) the carrier unit by means of a lifting unit for lifting or lowering the carrier unit is moved from an opening and closing position where the upper surface of the carrier unit is in a position that enables the opening mechanism to take off or put on the substrate container lid of a substrate container that is present on the upper surface of the carrier unit; to a transfer position where the upper surface of the carrier unit is in a position that enables a substrate to be transferred from a substrate container that is present on the upper surface of the carrier unit.

32. The method according to claim 31, wherein upon opening of the substrate container in step (d) a pressure is set in the load chamber that differs from the environmental pressure.

Description

[0057] In the following, the invention is explained in detail by way of examples, that are not to limit the invention, with reference to the drawings. Here,

[0058] FIG. 1 shows a substrate container according to the prior art;

[0059] FIG. 2 shows schematic views of one embodiment of a load lock according to the invention in the closed state (FIG. 2a: plan view; FIG. 2b: front view);

[0060] FIG. 3 shows schematic views of the embodiment of a load lock according to the invention in the open state shown in FIG. 2 (FIG. 3a: plan view; FIG. 3b: front view);

[0061] FIG. 4 shows a perspective view especially of the load chamber of the embodiment of the load lock according to the invention shown in FIG. 2;

[0062] FIG. 5 shows a schematic view of a device for processing flat substrates according to the invention;

[0063] FIG. 6 shows a schematic view of an embodiment of a load lock according to the invention for illustration of the method according to the invention, wherein a substrate container is in the opening and closing position;

[0064] FIG. 7 shows a further schematic view of an embodiment of a load lock according to the invention for illustration of the method according to the invention, wherein a substrate container is in the transfer position; and

[0065] FIG. 8 shows simplified views of an embodiment of a load lock according to the invention for illustration of the method according to the invention.

[0066] FIG. 1 shows a substrate container 201 with a housing 202 having a bottom 203, a ceiling 204 as well as side walls 205. The housing 202 has an access opening 206 via which substrates 301 can be inserted into the substrate container 201 and via which the substrates can be taken out of the substrate container 201. The access opening is formed on the front side of the housing 202. A lid 207 is provided for closing the access opening 206 which in FIG. 1 has already been removed from the access opening, so that FIG. 1 shows an opened substrate container. Handles are formed on two opposite side walls 205 that are to facilitate setting down and picking up of the substrate container 201. Positioning pegs 208 and recesses 209 are formed on the outside of the lid 207. The positioning pegs 208 enable the lid 207 to be positioned on the opening mechanism 31. The recess 209 enables mechanical interaction with the opening mechanism 31 to take off the lid 207 of the housing 202 to open the substrate container 201 and to attach it to the housing 202 to close the substrate container 201. The substrate container may be a standard substrate container in accordance with SEMI E47.1-0704 Provisional Mechanical Specification for FOUPS Used to Transport and Store 300 mm Wafers.

[0067] FIGS. 2 and 3 show an embodiment of the load lock 1 according to the invention. Load lock 1 has a load chamber 2 that has a bottom 3, a ceiling 4, a rear wall 5, a front wall 6, a first side wall 7, and a second side wall 8 that define an interior 9. Here, the rear wall 5 and the front wall 6 are located opposite to each other. The rear wall 5 and the front wall 6 are connected to each other via the first and second side walls 7, 8. The load chamber 2 can be divided into a first part 10 and a second part 11. The dividing plane extends in a vertical plane at points A, B, C, and D in FIG. 2 bis 4 (x,y plane of Cartesian coordinate system). Here, the dividing plane extends toward the rear wall offset to the front wall through the first side wall 7, the second side wall 8, the bottom 3, and the ceiling 4 of the load chamber 2. The first part 10 of the load chamber 2 has a circumferential edge 21 that fits to a circumferential edge 22 of the second part 11 in a pressure-tight manner in the closed state of the load chamber 2. For that, sealing means 20 are provided on the whole edge 21 of the first part 10 and/or on the whole edge 22 of the second part 11 (see also FIG. 6). The first part 10 and the second part 11 are connected to each other via a hinge 12 on a vertical axis that extends through points B and D of the dividing plane and lies on the y coordinate. To open the load chamber 2 the second part 11 is pivoted by means of the hinge 12 about the vertical axis B-D. Thereby, the first part 10 is separated from the second part 11, so that the first part 10 on its edge 21 and the second part 11 on its edge 22 are exposed. To facilitate opening and closing of the load chamber 2 a handle 13 may be attached to the outside of the front wall 6.

[0068] In the interior 9 of the load chamber 2 there is a carrier unit 14. The carrier unit 14 has a base element 15 (see FIG. 6) with an upper surface 16 and a lower surface 17. Here, the upper surface 16 is in a horizontal plane. A tie plate 18 is arranged on the upper surface 16 of the base element 15. The substrate container 201 can be put down to the tie plate 18 with its lower surface, bottom 203. To position the substrate container 201 on the tie plate 18, positioning pins 19 are provided on its upper surface that facilitate the positioning of the substrate container 201 on the carrier unit 14 in a given position. The interior 9 of the load chamber 2 is dimensioned such that the bottom 3, the ceiling 4, the rear wall 5, the front wall 6, the first side wall 7, and the second side wall 8 are spaced apart from the substrate container 201 that is put down to the carrier unit 14 in the given position.

[0069] For lifting and lowering the carrier unit 14 a lifting unit 23 is provided. The lifting unit 23 has a guide 24 for vertically guiding a lifting rod 25. The guide 24 is arranged outside of the load chamber 2. The lifting rod 25 extends in the vertical direction (y coordinate) over a sealed bushing 26 in the bottom 3 of the load chamber 2 into the interior 9 of the load chamber 2. Thereon the carrier unit 14 rests with its lower surface 17. The carrier unit 14 has a slide 27 that holds the base element 15. The slide 27 runs in a vertical guide rail 28 that is arranged on the rear wall of the load chamber 2. By means of the lifting unit 23 the carrier unit 14 guided in the guide rail 28 can be lifted and lowered in the vertical direction (double arrow A). For that, the lifting unit 23 has a drive 38 that is arranged outside the load chamber 2.

[0070] In the rear wall 5 of the load chamber 2 a lock opening 29 is formed that enables transfer of a substrate 301 out of an opened substrate container 201 that is present in the load chamber 2 to a device 101 for processing flat substrates or vice versa. Device 101 has a handling system 102 which may be a robot with a gripping arm 103 (see FIG. 5). Gripping arm 103 may be passed through the lock opening 29 in the opened substrate container 201 to transfer a substrate 301 to there put down or take up a substrate 301. The lock opening 29 is arranged in the geometric center of the rear wall 5. Lock opening 29 is closed by means of a lock valve 30. To transfer a substrate 301 from the load chamber 2 to the device 101 and out of the device 101 into the load chamber 2 the lock valve 30 is opened.

[0071] The load lock 1 further has an opening mechanism 31 with which the substrate container lid 207 may be taken off from the access opening 206 and put onto to the access opening 206. The opening mechanism 31 is arranged within the load chamber above the lock opening 29. The opening mechanism 31 has engagement means 32 that can be engaged with the recesses 209 formed in the lid 207. Here, the engagement means 32 can interact with an interlocking mechanism that blocks the engagement means 32 in the recesses 209 or unlocks the engagement means 32 blocked there. The opening mechanism 31 has guide means 33 for the engagement means 32. By means of the guide means the engagement meansand with them the lid 207 if the engagement means 32 are blocked in the recesses 209 of the lid 207in horizontal direction (double arrow B) can be moved. The guide means 33 are guided through bushings 34 that are formed in the rear wall 5 of the load chamber 2. The opening mechanism 31 has drives 36 that are arranged outside the load chamber 2.

[0072] The load chamber 2 has one or more terminals 37 via which by means of a pressure adjusting means (not shown) a pressure p.sub.2 can be adjusted in the load chamber 2 that differs from the environmental pressure p.sub.1, generally atmospheric pressure.

[0073] On the rear wall 5 of the load chamber 2 an identification system 39 in the form of a sensor is arranged, namely above the lock opening 29 and below the opening mechanism 31. By means of the identification system 39 the substrate container 201 that is present in the load chamber 2 and/or the substrates 301 that are present in the substrate container can be identified.

[0074] The load lock 2 is attached to a device 101 for processing flat substrates. The device 101 is a pressure process plant. It has a process chamber 104 in which flat substrates can be processed. The process chamber 104 is connected to a handling chamber 105 via a lock 106. On the handling chamber 105 two load locks 1 according to the invention are arranged. Here, the lock openings 29 are arranged in alignment with the openings of the handling chamber 105. In the handling chamber 105 there is the handling system 102 with its gripping arm 103. By means of the handling system 102 a substrate 301 can be taken out of one of the load locks 1 and transferred to the process chamber 104 and vice versa. For that, the handling system 102 with the substrate 301 held by the gripping arm 103 is able to rotate about a vertical axis within the handling chamber 105 (double arrow C). In FIG. 5 in both load locks 1 a flat substrate 301 with a square cross section is shown in addition to a flat substrate 301 that has a circular cross section.

[0075] FIGS. 8a to 8m illustrate one embodiment of the method according to the invention. Here, the load lock 2 is depicted very simplified, each. In the example shown, it is started with an empty load chamber 2 into which a substrate container 201 is to be introduced that contains substrates 301. That is, first, the load chamber 2 is empty and closed (FIG. 8a). The upper surface of the carrier unit 14 is in a starting position, i.e. at a height relative to the vertical coordinate y that approximately corresponds to half the height of the interior 9 of the load chamber 2. In this example, the starting position corresponds to a transfer position, i.e. a position that enables transfer of a substrate 301 out of a substrate container 201 if an opened substrate container 201 would be present on the upper surface of the carrier unit 14. The pressure p.sub.2 in the load chamber corresponds to the environmental pressure p.sub.1.

[0076] Now, the load chamber 2 is opened (FIG. 8b). For that, the load chamber 2 is separated along the dividing plane into a first part 10 and a second part 11. Subsequently, a substrate container 201 containing substrates 301 is put down to the carrier unit 14 (FIG. 8c), so that it is in a given position on the carrier unit 14. Now, the load chamber 2 is transferred to its closed state (FIG. 8d) by re-combining the second part 11 with the first part 10. Subsequently, the substrate container 201 can be lifted from the starting position along a vertical axis to the opening and closing position (FIG. 8e, see also arrow A in FIG. 6). In the opening and closing position the lid 207 is taken off of the substrate container 201 by means of the opening mechanism 31 (FIG. 8f) and held by the opening mechanism 31 until it is put down again (see arrow B in FIG. 6). After having taken off the lid 207 the interior of the substrate container now is accessible and is ready to at least approximately adapt the pressure to the pressure in the process chamber of the pressure process plant 101. The opened substrate container 201 is lowered from the opening and closing position to the identification position (FIG. 8g). There, the substrate container 201 and/or the substrates 301 contained therein can be identified by means of the identification system 39. Subsequently, pressure compensation is carried out. Here, it is adjusted a pressure p.sub.2 in the load chamber 2 via the terminal 37 that differs from the environmental pressure p.sub.1. Pressure p.sub.2 is at least approximately in the same order as the pressure at which processing of the substrate 301 is to be performed in the pressure process plant 101. An exact pressure control can separately take place in the sealable process chamber 104.

[0077] After pressure compensation the open substrate container 201 is lowered from the identification position to a transfer position (FIG. 8h, see also FIG. 7). In the transfer position a substrate 301 that is to be taken out of the substrate container 201 is at the height of the lock opening 29. The lock valve is opened whereby the lock opening 29 is open. Now, substrate 301 is moved into the handling chamber 105 (not shown) through the opened lock valve 30 and thus, through the lock opening 29.

[0078] If further substrates 301 are to be taken out of the substrate container 201, the substrate container 201 has to be transferred to the transfer positions where the respective substrate is at the height of the lock opening 29. However, this is not shown in FIG. 8. The figures following FIG. 8h show the further procedure when the substrate container 201, from which the substrate 301 just has been taken out, is to be taken out of the load lock 2. For that the lock valve 30 is closed, so that pressure compensation is enabled again. Here, pressure p.sub.2 is brought to the environmental pressure p.sub.1 again. Subsequently, the substrate container 201 is lifted from the transfer position to the opening and closing position and the lid 207 is put down to the substrate container 201 again by means of the opening mechanism 31 (FIG. 8i). Then, the closed substrate container 201 is lowered to the starting position (FIG. 8j). Then, the load chamber 2 is opened by dividing it along the dividing plane into a first part 10 and a second part 11 (FIG. 8k). Then, the substrate container 201 is taken out of the load chamber 2 (FIG. 8l). After having closed the load chamber, the state shown in FIG. 8a is obtained (FIG. 8m).

[0079] FIGS. 6 and 7 show the load lock according to the invention together with a part of the handling chamber 105. However, this is not part of the load lock 2. Rather, there is shown a part of the handling chamber 105 to illustrate that the lock opening of the load chamber 2 abuts on an opening in the handling chamber 105.

LIST OF REFERENCE NUMBERS

[0080] 1 load lock [0081] 2 load chamber [0082] 3 bottom [0083] 4 ceiling [0084] 5 rear wall [0085] 6 front wall [0086] 7 first side wall [0087] 8 second side wall [0088] 9 interior [0089] 10 first part [0090] 11 second part [0091] 12 hinge [0092] 13 handle [0093] 14 carrier unit [0094] 15 base element [0095] 16 upper surface [0096] 17 lower surface [0097] 18 tie plate [0098] 19 positioning pin [0099] 20 sealing means [0100] 21 edge [0101] 22 edge [0102] 23 lifting unit [0103] 24 guide [0104] 25 lifting rod [0105] 26 bushing [0106] 27 slide [0107] 28 guide rail [0108] 29 lock opening [0109] 30 lock valve [0110] 31 opening mechanism [0111] 32 engagement means [0112] 33 guide means [0113] 34 bushing [0114] 36 drive [0115] 37 terminal [0116] 38 drive [0117] 39 identification system [0118] 101 pressure process plant [0119] 102 handling system [0120] 103 gripping arm [0121] 104 process chamber [0122] 105 handling chamber [0123] 106 lock [0124] 201 substrate container [0125] 202 housing [0126] 203 bottom [0127] 204 ceiling [0128] 205 side wall [0129] 206 access opening [0130] 207 lid [0131] 208 positioning peg [0132] 209 recess [0133] 301 substrate