OPENER FOR EXTREME ULTRA VIOLET LITHOGRAPHY RETICLE PODS
A two stage opener (50) for an EUV RSP (32, 34) includes an outer RSP pod opener (42, 44) having: 1. a RSP latch mechanism (42rlm) for latching a sealed outer RSP pod (32, 34) in place on the RSP pod opener (42, 44) and 2. a RSP lock/unlock mechanism (42lulm) for unlocking the RSP pod (32, 34) so the RSP pod opener (42, 44) can separate a RSP pod cover (32c, 343c) from a RSP pod door (32d, 34d). After the RSP lock/unlock mechanism (42lulm) unlocks the RSP pod (32,34), the RSP pod opener (42, 44) separates the RSP pod door (32d, 34d) from the RSP pod cover (32c, 34c) thereby exposing a metal case (20). The pod opener (50) also includes a metal case opener (52) having at least two (2) arms (56) for receiving and supporting the metal case cover (22) while the two stage pod opener (50) separates the metal case base (24) from the metal case cover (22) thereby exposing the hare reticle (26) carried on the metal case base (24).
The present disclosure relates generally to the technical field of photolithographic manufacturing equipment and, more particularly, to openers for pods that enclose a photolithographic reticle.
BACKGROUND ARTAs semiconductor line width continue shrinking below 22 nm circuit printing lithography tools can no longer use a conventional photo mask (also known as the reticle) that is covered by a pellicle film. When using an extra deep UV (“EUV”) light source, that is necessary for printing a lithographic pattern having line widths below 22 nm on a product, the pellicle's film distorts and/or absorbs the light thereby diminishing image quality. To avoid pattern distortion, exposing a lithography pattern having line widths below 22 nm requires using both:
1. the EUV light source; and
2. a bare glass photo mask.
Historically, a protective pellicle film has been a critical for preventing particles from landing directly on the photo mask patterned glass surface. Contamination of a reticle's patterned glass surface by particles has an immediate impact on the yield of printed products, i.e. the yield of integrated circuit (“IC”) die on a wafer. Removing the pellicle film from the reticle to accommodate 22 nm or narrower line width lithographic printing creates a problem for storing and carrying bare glass reticles while concurrently avoiding particle contamination when using the photo mask.
The Semiconductor Equipment and Materials International's (“SEMI's”) solution for storing and carrying bare glass reticles in a typical clean room environment is:
-
- 1. a metal case, identified by the general reference number 20 in
FIG. 1A , for carrying the bare glass reticle; that is enclosed within - 2. a conventional plastic case.
The illustration ofFIG. 1A depicts the metal case 20 when open with its cover 22 above its base 24 with a photo mask 26 (reticle 26) resting on the base 24. The conventional plastic cases used for storing and carrying a bare glass reticle 26 enclosed in the metal case 20 is known as the reticle Standard Mechanical InterFace (“SMIF”) Pod or RSP.FIG. 1B depicts a 200 mm RSP, referred to by the general reference number 32, that may enclose the metal case 20, andFIG. 1C depicts a 150 mm RSP, referred to by the general reference number 34, that may also enclose the metal case 20. The primary differences between the two different RSPs 32, 34 are their respective:
- 1. a metal case, identified by the general reference number 20 in
1. mechanical dimensions; and
2. locking mechanism and location.
SEMI standards specify configurations for the two different RSPs 32, 34 and the metal case 20. The SEMI standard envisions keeping the metal case 20 closed whenever it is outside an ultra-clean environment that is free of contaminating particles such as when the metal case 20 is outside a vacuum chamber.
In accordance with the SEMI standard, the cover 22 of a closed metal case 20 does not lock onto the base 24. That is, the cover 22 of a closed metal case 20 lifts easily off the base 24 to expose the reticle 26 stored inside. The SEMI standard also provides a detailed specification for handles located on the cover 22 so the cover 22 can be lifted from the base 24 either manually by a human operator or automatically by a mechanical mechanism.
Similar to the metal case 20, both RSPs 32, 34 include a cover that may be separated from their base. The upper half of the RSPs 32, 34 is commonly known as or called respectively the pod cover 32c, 34c, and the lower half of the RSPs 32, 34 is commonly known as or called the pod door 32d, 34d. As illustrated respectively in
Everyone designing and manufacturing the EUV RSPs 32, 34 must comply with SEMI standards so EUV pod opener manufacturers can design proprietary opening/closing mechanisms that comply with the appropriate SEMI standard. Consequently, the design of the metal case 20 and the RSPs 32, 34 is not a subject of this disclosure.
DISCLOSUREAn object of the present disclosure is to provide an opener for a pod that encloses and carries a bare photolithographic reticle.
Yet another object of the present disclosure is to provide an opener for a pod that encloses and carries a bare photolithographic reticle which is simple.
Yet another object of the present disclosure is to provide an opener for a pod that encloses and carries a bare photolithographic reticle which is durable.
Yet another object of the present disclosure is to provide an opener for a pod that encloses and carries a bare photolithographic reticle that is cost effective.
Yet another object of the present disclosure is to provide an opener for a pod that encloses and carries a bare photolithographic reticle that is easy to manufacture.
Yet another object of the present disclosure is to provide an opener for a pod that encloses and carries a bare photolithographic reticle that is easy to maintain.
Yet another object of the present disclosure is to provide an opener for a pod that encloses and carries a bare photolithographic reticle that is economical to manufacture.
Yet another object of the present disclosure is to provide an opener for a pod that encloses and carries a bare photolithographic reticle that forestalls reticle contamination.
Briefly, disclosed herein is a two stage pod opener for a pod that encloses and carries a bare photolithographic reticle. The reticle enclosing pod includes an outer RSP pod having:
-
- 1. a RSP pod door that is adapted for receiving a metal case, the metal case being adapted for receiving and enclosing the bare reticle; and
- 2. a RSP pod cover that mates with and locks to the RSP pod door thereby enclosing the metal case within the sealed outer RSP pod.
The metal case includes: - 1. a metal case base that is adapted for receiving the bare reticle; and
- 2. a metal case cover that mates with the metal case base having the bare reticle received thereon thereby enclosing the bare reticle within the metal case within the sealed outer RSP pod.
The two stage pod opener includes an outer RSP pod opener that includes: - 1. a RSP latch mechanism for latching the sealed outer RSP pod in place on the outer RSP pod opener; and
- 2. a RSP lock/unlock mechanism for unlocking the outer RSP pod so the outer RSP pod opener can separate the RSP pod cover from the RSP pod door.
After the RSP lock/unlock mechanism unlocks the outer RSP pod, the outer RSP pod opener separates the RSP pod door from the RSP pod cover thereby exposing the metal case. The two stage pod opener also includes a metal case opener having at least two (2) arms for receiving and supporting the metal case cover while the two stage pod opener separates the metal case base from the metal case cover thereby exposing the bare reticle carried on the metal case base.
These and other features, objects and advantages will be understood or apparent to those of ordinary skill in the art from the following detailed description of the preferred embodiment as illustrated in the various drawing figures.
The two stage EUV pod openers disclosed herein are adaptations of existing opener mechanisms marketed commercially by Fortrend Engineering Corporation respectively:
-
- 1. identified by the general reference number 42 in
FIG. 3A for opening and closing the SEMI standard E-19.4 200 mm RSP 32; or - 2. identified by the general reference number 44 in
FIG. 3B for opening and closing the SEMI standard E-100 150 mm RSP 34.
The adaptation of the standard Fortrend Engineering Corporation RSP pod openers 42, 44 adds a second mechanism for opening the inner metal case 20 the after opening the RSPs 32, 34. In other words, the EUV pod opener disclosed herein has two sub-assemblies. The first assembly (the existing RSP pod openers 42, 44) is the mechanism that opens the RSPs 32, 34; and the second assembly, an inner casing opener, is a mechanism that opens the metal case 20. Since the metal case 20 cannot be accessed until the RSPs 32, 34 has been opened, the following section describes the 200 mm RSP pod opener 42 illustrated inFIG. 3A to describe its structure and exemplify the complete opening sequence for the 200 mm RSP 32. The 150 mm RSP pod opener 44 operates similarly to the following description except that the pod locking mechanism differs from that of the 200 mm RSP pod opener 42. The lock/unlock mechanism included in either of the RSP pod openers 42, 44 is not a subject of this disclosure.
- 1. identified by the general reference number 42 in
The 200 mm RSP Pod Opener 42
The 200 mm RSP pod opener 42 opener is a “3-axis” motorized system that includes:
-
- 1. a RSP latch mechanism 42rlm illustrated in
FIGS. 4A and 4B that is located at the top of the 200 mm RSP pod opener 42; - 2. a RSP lock/unlock mechanism 42lulm illustrated in
FIG. 4C that is located beneath a pod table 42pt that is depicted inFIG. 4B ; and - 3. a pod table elevator 42pte illustrated in
FIG. 4D-4G .
The RSP latch mechanism 42rlm uses a dual-motor, dual-latch mechanism. When the 200 mm RSP 32 rests on the pod table 42pt of the 200 mm RSP pod opener 42 depicted inFIG. 4 , the RSP latch mechanism 42rlm latches the 200 mm RSP 32 in place. The RSP latch mechanism 42rlm includes two (2) latch assemblies 42la depicted inFIGS. 4A and 4B that are respectively located along opposite sides of the 200 mm RSP pod opener 42. Each latch assembly 42la includes a linear motor 42lm driving a friction rod 42fr linearly. A 90-degree angled arm 42aa is located atop a rotation shaft 42rs that is encircled by an O-ring 42or that also presses against the friction rod 42fr. Moving the friction rod 42fr linearly rotates the O-ring 42or together with the rotation shaft 42rs thereby latching the 200 mm RSP 32 onto the pod table 42pt. The latch assemblies 42la are positioned symmetrically on opposite sides of the 200 mm RSP 32 preferably for locking the 200 mm RSP 32 along its front and rear edges. Alternatively, if required the latch assembly 42la can also be located for locking the 200 mm RSP 32 along the left and right edges.
- 1. a RSP latch mechanism 42rlm illustrated in
As depicted in
As also depicted in
After the RSP lock/unlock mechanism 42lulm unlocks the 200 mm RSP 32 thereby allowing the pod door 32d to be separated from the pod cover 32c, the pod table elevator 42pte illustrated in
Two Stage Pod Opener 50
A two stage pod opener 50 in accordance with the present disclosure depicted in
As illustrated in
Each arm 56 attaches by a linkage 62 to one end of a single axis linear motor 64 that is also secured to the base plate 54. One end of each linear motor 64 passes through a linear bearing guide 66 before connecting to one of the two (2) linkages 62. Energizing the linear motor 64 pulls on one of the arms 56 included in each inner metal case opener 52 while simultaneously pushing on the other arm 56. Force applied by the linear motor 64 to the pair of arms 56 of each inner metal case opener 52 causes both arms 56 to rotate about their respective pivot points 58 and swing toward the opposite inner metal case opener 52.
With the pod table 42pt located in the inner metal case open/close position, the configuration of the inner metal case openers 52 and their respective attachment to the 200 mm RSP pod opener 42 positions extended ends of the arms 56 as illustrated in
To ensure the cleanliness of the two stage pod opener 50, all moving parts that might create particles due to surface contact or friction are located in a contamination containing environment. Accordingly, as depicted in
-
- 1. located on a back side of the two stage pod opener 50 furthest from the pod table 42pt; and
- 2. separated from the pod table 42pt and the pod door 32d resting thereon by a wall 74.
Similar to the sealed cover 72, a sealed cover 76, depicted partially cut away inFIG. 4F so the elevator drive motor 42edm is visible, closes the back side of the two stage pod opener 50 where the linear bearings 42lb, lead screw 42ls and elevator drive motor 42edm are located. To ensure that a low pressure environment surrounds pod table elevator 42pte, multiple exhaust ports 78 depicted inFIG. 4F are positioned along the lower edge of the two stage pod opener 50. Lastly, as depicted inFIG. 9 a sealed cover 82 encloses the mechanism of each of the two (2) inner metal case openers 52, and exhaust ports 82 located at one end of each base plate 54 ensures that a low pressure environment surrounds each inner metal case openers 52. Including the exhaust ports 78 and the exhaust ports 82 permits vacuum applied thereto to establish a low pressure environment respectively around pod table elevator 42pte and each of the two (2) inner metal case openers 52 for removing particles produced respectively thereby from the two stage pod opener 50.
Although the present invention has been described in terms of the presently preferred embodiment, it is to be understood that such disclosure is purely illustrative and is not to be interpreted as limiting. Consequently, without departing from the spirit and scope of the disclosure, various alterations, modifications, and/or alternative applications of the disclosure will, no doubt, be suggested to those skilled in the art after having read the preceding disclosure. Accordingly, it is intended that the following claims be interpreted as encompassing all alterations, modifications, or alternative applications as fall within the true spirit and scope of the disclosure.
Claims
1. A two stage pod opener for opening a pod that encloses and carries a photolithographic reticle therein, the pod including: the two stage pod opener comprising:
- a. an outer RSP pod having: i. a RSP pod door that is adapted for receiving a metal case, the metal case being adapted for receiving and enclosing a bare reticle; and ii. a RSP pod cover that mates with and locks to the RSP pod door thereby enclosing the metal case within the sealed outer RSP pod,
- b. the metal case including: i. a metal case base that is adapted for receiving the bare reticle; and ii. a metal case cover that mates with the metal case base having the bare reticle received thereon thereby enclosing the bare reticle within the metal case within the sealed outer RSP pod,
- a. an outer RSP pod opener that includes: i. a RSP latch mechanism for latching the sealed outer RSP pod in place on the outer RSP pod opener; and ii. a RSP lock/unlock mechanism for unlocking the outer RSP pod so the outer RSP pod opener can separate the RSP pod cover from the RSP pod door; after the RSP lock/unlock mechanism unlocks the outer RSP pod, the outer RSP pod opener separating the RSP pod door from the RSP pod cover thereby exposing the metal case;
- b. a metal case opener that includes at least two (2) arms for receiving and supporting the metal case cover while the two stage pod opener separates the metal case base from the metal case cover thereby exposing the bare reticle carried on the metal case base.
2. The two stage pod opener of claim 1 wherein the outer RSP pod opener includes an elevator adapted for lowering a pod table that receives the RSP pod door of the outer RSP pod when enclosing the bare reticle, the outer RSP pod opener separating the RSP pod door from the RSP pod cover thereby exposing the metal case by lowering the pod table carrying the RSP pod door downward from the RSP pod cover.
3. The two stage pod opener of claim 2 wherein a sealed cover about the elevator forestalls contaminating the bare reticle with particles produced by the elevator.
4. The two stage pod opener of claim 3 wherein at least one exhaust port coupled to the sealed cover permits establishing a low pressure environment about the elevator.
5. The two stage pod opener of claim 2 wherein the pod table also carries the RSP lock/unlock mechanism.
6. The two stage pod opener of claim 5 wherein a sealed cover about the RSP lock/unlock mechanism forestalls contaminating the bare reticle with particles produced by the RSP lock/unlock mechanism.
7. The two stage pod opener of claim 2 wherein the elevator lowers the RSP pod door to an inner metal case open/close position thereby juxtaposing the metal case carried on the RSP pod door with the metal case opener.
8. The two stage pod opener of claim 7 wherein positioning each of the arms of the metal case opener for receiving and supporting the metal case cover includes rotating the arms about respective pivot points.
9. The two stage pod opener of claim 8 wherein the two stage pod opener separates the metal case base from the metal case cover by lowering the pod table carrying the RSP pod door downward from the metal case cover.
10. The two stage pod opener of claim 1 wherein a sealed cover about the metal case opener forestalls contaminating the bare reticle with particles produced by the metal case opener.
11. The two stage pod opener of claim 10 wherein at least one exhaust port coupled to the metal case opener permits establishing a low pressure environment about the metal case opener.
12. The two stage pod opener of claim 1 wherein positioning each of the arms of the metal case opener for receiving and supporting the metal case cover includes rotating the arms about respective pivot points.
13. The two stage pod opener of claim 12 wherein an elevator included in the two stage pod opener that is adapted for lowering a pod table that receives the RSP pod door of the outer RSP pod that carries the metal case separates the metal case base from the metal case cover by lowering the pod table carrying the RSP pod door downward from the metal case cover.
14. The two stage pod opener of claim 13 wherein a sealed cover about the elevator forestalls contaminating the bare reticle with particles produced by the elevator.
15. The two stage pod opener of claim 14 wherein at least one exhaust port coupled to the elevator permits establishing a low pressure environment about the elevator.
Type: Application
Filed: May 2, 2011
Publication Date: Feb 21, 2013
Inventor: Kung Chris Wu (Cupertino, CA)
Application Number: 13/695,286
International Classification: A47B 81/00 (20060101);