WO2021207311A1

WO2021207311A1 - Sample carrier cleaner

Info

Publication number: WO2021207311A1
Application number: PCT/US2021/026112
Authority: WO
Inventors: Yi-Chuan Peng; Ko-Hsi CHAN; Shih Tsung Chen
Original assignee: Pintek Solutions Corporation
Priority date: 2020-04-08
Filing date: 2021-04-07
Publication date: 2021-10-14
Also published as: TWI781577B; TW202141669A; TW202231371A

Abstract

This invention provides a method and a system for cleaning a container with a body and a door. The door has an internal side for engaging with the body and an external side outside the container. The external side is cleaned by purging a gas flow from upside down. A conical shelter includes a square opening for engaging with the internal side of the door. A first nuzzle provides a DI water beam and a gas flow to the internal side of the door from bottom upward with an angle, and a second nuzzle provides a DI water beam and a gas flow inside the container with an angle. The shelter prevents the DI water beam from contaminating inside structure of the door.

Description

Sample Carrier Cleaner

FIELD OF THE INVENTION

[0001] The invention relates to a method and a system for cleaning a sample carrier, and more particularly to a method and a system for cleaning a door and a body of a FOUP in semiconductor manufacturers. However, it would be recognized that the invention has a much broader range of applicability.

BACKGROUND OF THE INVENTION

[0002] The following description and examples are not admitted to be prior art by virtue of their inclusion in this section.

[0003] In the field of semiconductor manufacturing process, samples, transferred among different process stages, include wafer, mask, reticle, or others. A wafer, also called a slice or substrate, is a thin slice of semiconductor, such as a crystalline silicon, used for fabrication of integrated circuits and, in photovoltaics, to manufacture solar cell. This kind of silicon wafer serves as the substrate for microelectronics devices built in and upon the wafer, under many microfabrication processes, such as doping, ion implantation, etching, thin film deposition, and photolithographic patterning. Some other compound semiconductors such as GaAs or SiC could be provided as wafers for LED manufacturing. Some other materials could be also provided as wafers in some specific application, such as sapphire provided as GaN epitaxial growth and glass for TFT(thin film transistor) fabrication. A mask is a template used in the lithography for transferring patterns thereon to the wafer, and has identical dimension of patterns to the patterns on the wafer. A reticle is also a template used in the lithographic process but has larger patterns, usually quadruple, compared to the patterns on the wafer.

[0004] A container for storing any kind of the samples may include cassettes, carrier, tray, FOUP(Front Opening Unified Pod), FOSB(Full Pitch Front Opening Shipping Boxes), SMIF(Standard Mechanical Interface), MAC(Multi Application Carrier), pod, or box. The purpose of the containers is to provide an ultrahigh cleaning environment in a local, small space, because it is easier to keep ultrahigh cleaning environment inside a small space than in a very large factory. Different containers are developed under different process demands with evolution of semiconductor history. [0005] The container itself must be cleaned periodically. The current art is to put the container inside a cleaning chamber and detergent is purged by using high pressure to inside and outside of the container.

[0006] The current container for transferring the samples in the semiconductor is FOUP which includes a door and a body. When the FOUP needs to be cleaned, the door is detached or separated from the body first. Then, inside and outside of the body is cleaned, and inside of the door is also cleaned. Outside surface of the door is usually not cleaned.

[0007] The present apparatus for cleaning the FOUP needs a relative longer time and will lower throughput to the semiconductor manufacturers.

[0008] The mechanism for cleaning the FOUP is also relative complex which will incur more cost to the semiconductor manufacturers.

[0009] Moreover, the cleaning apparatus will have relatively larger foot print which will incur overhead running cost in the area of clean room for the semiconductor manufacturers.

BRIEF SUMMARY OF THE INVENTION

[0010] The object of this invention is to provide an environment of positive pressure to prevent DI water for cleaning FOUP door from entering the inside structure of the FOUP door.

[0011] The object of this invention is to provide a shelter to prevent DI water for cleaning FOUP door from entering the inside structure of the FOUP door.

[0012] The object of this invention is to provide a system with simple structure for cleaning FOUP, and cost of the system could be lowered.

[0013] The object of this invention is to provide a system for cleaning FOUP with small foot print, and overhead running cost of the semiconductor manufacturers can be lowered.

[0014] Accordingly, the invention provides a method for cleaning a door of a container, which comprises steps of providing a conical shelter with an opening, placing the door on the shelter with the opening engaging with an internal side of the door downward, and spraying a DI water beam under the shelter to the internal side of the door with an angle, wherein the shelter prevents the DI water beam from contaminating an inside structure of the door.

[0015] The method according to the present invention, the shelter is waterproof.

[0016] The method according to the present invention, the shelter has a straight section line, a curved section line, or a poly section line. [0017] The method according to the present invention further comprises a step of providing a positive pressure environment by purging a gas flow to an external side of the door, wherein the external side faces upward, before said spraying step.

[0018] The method according to the present invention, the gas flow is a nitrogen flow or a clean dry air flow.

[0019] The present invention further provides a method for cleaning a door of a container, which comprises steps of providing a positive pressure environment by purging a gas flow to an external side of the door, wherein the external side faces at a first direction, and spraying a DI water beam from a second direction, opposite to the first direction, to an internal side of the door with an angle, wherein the gas flow along the door prevents the DI water beam from contaminating an inside structure of the door.

[0020] The method according to the present invention, the gas flow is a nitrogen flow, or a clean dry air flow.

[0021] The present invention further provides a method for cleaning a container, which comprises steps of separating a door from the container; placing the container in a chamber with an opening thereof downward; configuring a conical shelter with a square opening on the container; placing the door on the shelter with an external side of the container upward, and an internal side of the door engaging with the square opening; purging a main gas flow upside down to the external side of the door; spraying a first DI water beam to the internal side with a first angle; purging a first declined gas flow to the internal side with a second angle; spraying a second DI water beam inside the container with a third angle; purging a second declined gas flow inside the contained with a fourth angle; spinning the door and the container; and drying the container and the door.

[0022] The method according to the present invention, the shelter is waterproof.

[0023] The method according to the present invention, the shelter has a straight section line, a curved section line, or a poly section line.

[0024] The method according to the present invention, the main gas flow, the first declined gas flow, and the second declined gas flow are a nitrogen flow or a clean dry air flow.

[0025] The method according to the present invention, an angle between a fringe of the shelter and the door is within ±85°. [0026] The method according to the present invention, said step of purging the first DI water beam and said step of purging a first declined gas flow are alternatively, and said step of purging the second DI water beam and said step of purging a second declined gas flow are alternatively.

[0027] The method according to the present invention, said step of purging the first DI water beam and said step of purging a first declined gas flow are alternatively, and said step of purging the second DI water beam and said step of purging a second declined gas flow are alternatively.

[0028] The present invention further provides a system for cleaning a container, which comprises a conical shelter with an opening for engaging an internal side of a door of the container; a main nuzzle for purging a main gas flow upside down to an external side of the door; a first nuzzle for spraying a first DI water beam to the internal side with a first angle, and for purging a first declined gas flow to the internal side with a second angle; a second nuzzle for spraying a second DI water beam to an inside surface of the contained with a third angle, and for purging a second declined gas flow to the inside surface of the container with a fourth angle; a motor for rotating the container and the door; and a heater for drying the container and the door.

[0029] The system according to the present invention, the shelter is waterproof.

[0030] The system according to the present invention, an angle between a fringe of the shelter and the door is within ±85°.

[0031] The system according to the present invention, the main gas flow, the first declined gas flow, and the second declined gas flow are a nitrogen flow or a clean dry air flow.

[0032] The system according to the present invention further comprises a frame, for the container to be placed, engaging with the motor and the shelter.

[0033] The system according to the present invention further comprises a cleaning chamber for enclosing said frame, said main nuzzle, said first nuzzle, said second nuzzle, and said shelter.

[0034] The system according to the present invention, the cleaning chamber encloses said heater.

[0035] Other advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS [0036] Further advantages of the present invention may become apparent to those skilled in the art with the benefit of the following detailed description of the preferred embodiments and upon reference to the accompanying drawings in which:

[0037] Figure 1A shows a top view of a FOUP body;

[0038] Figure IB shows a top view of a FOUP door;

[0039] Figure 1C is a schematic illustration of inside structures of a FOUP door;

[0040] Figure ID is a schematic illustration of the external side of the FOUP door;

[0041] Figure 2 is a schematic illustration of a frame for supporting and fixing the FOUP body, the shelter, and the FOUP door in accordance with one embodiment of the present invention;

[0042] Figure 3 is a schematic illustration of shelter configured with the frame, the FOUP body, and the FOUP door in accordance with one embodiment of the present invention;

[0043] Figure 4 shows a top view of the shelter in accordance with one embodiment of the present invention;

[0044] Figure 5 shows a side view of the shelter in accordance with one embodiment of the present invention;

[0045] Figure 6 is a schematic illustration of a system for cleaning FOUP in accordance with one embodiment of the present invention;

[0046] Figure 7 is a schematic illustration of a system for cleaning FOUP in accordance with another embodiment of the present invention; and

[0047] Figure 8 is a schematic illustration of purging DI water beams and all gas flows during cleaning process in accordance with one embodiment of the present invention;

[0048] While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and may herein be described in detail. The drawings may not be to scale. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.

DETAILED DESCRIPTION OF THE INVENTION [0049] As used herein, the term “sample” generally refers to wafers, masks or reticles. [0050] As used herein, the term “wafer” generally refers to substrates formed of a semiconductor or non- semiconductor material. Examples of such a semiconductor or non semiconductor material include, but are not limited to, monocrystalline silicon, polysilicon, silicon carbide, gallium arsenide, indium phosphide, and sapphire. Such substrates may be commonly found and/or processed in semiconductor fabrication facilities.

[0051 ] One or more layers may be formed upon a wafer. Many different types of such layers are known in the art, and the term wafer as used herein is intended to encompass a wafer on which all types of such layers may be formed. One or more layers formed on a wafer may be patterned. For example, a wafer may include a plurality of dies, each having repeatable patterned features. Formation and processing of such layers of material may ultimately result in completed semiconductor devices. As such, a wafer may include a substrate on which not all layers of a complete semiconductor device have been formed or a substrate on which all layers of a complete semiconductor device have been formed.

[0052] The wafer may further include at least a portion of an integrated circuit (IC), a thin- film head die, a micro-electro-mechanical system (MEMS) device, flat panel displays, magnetic heads, magnetic and optical storage media, other components that may include photonics and optoelectronic devices such as lasers, waveguides and other passive components processed on wafers, print heads, and bio-chip devices processed on wafers.

[0053] As used herein, the term “mask” or “reticle” generally refers to a substrate with patterns thereon which will be transferred to the wafer in the lithographic process. The substrate of mask or reticle may be quartz.

[0054] Turning now to the drawings, it is noted that the figures are not drawn to scale. In particular, the scale of some of the elements of the figures is greatly exaggerated to emphasize characteristics of the elements. It is also noted that the figures are not drawn to tie same scale. Elements shown in more than one figure that may be similarly configured have been indicated using the same reference numerals.

[0055] In the drawings, relative dimensions of each component and among every component may be exaggerated for clarity. Within the following description of the drawings the same or like reference numbers refer to the same or like components or entities, and only the differences with respect to the individual embodiments are described. [0056] Various example embodiments of the present invention will now be described more fully with reference to the accompanying drawings in which some example embodiments of the invention are shown. Without limiting the scope of the protection of the present invention, all the description and drawings of the embodiments will exemplarily be referred to container or carrier. However, the embodiments are not be used to limit the present invention to specific pod, box, container, or carrier.

[0057] In this invention, “container” means any cassette, holder, tray, carrier, FOUP(Front Opening Unified Pod), FSOB(Front-Opening Shipping Box), FOSB(Full Pitch Front Opening Shipping Boxes), SMIF(Standard Mechanical Interface), MAC(Multi Application Carrier), pod, or box with a door and a body which constitutes an ultrahigh clean environment for samples transferring in the semiconductor manufacturers.

[0058] One prior method for cleaning FOUP is provided and described by Rebstock in US 10,065,222, which purges recess and holes regions at outside of the FOUP and door with an air flow to prevent detergent from residing at these regions. Several cleaning embodiments are described with the gas flow to the recess and hole regions to block detergent entering the regions. In one embodiment, the door of the FOUP is placed at one side of the FOUP body and the door and body are spun as shown in Rebstock. This design will incur large footprint of the cleaning system.

[0059] Further, the outside surface of the door will not be cleaned in the commercial, available FOUP, because some holes at the outer surface of the door are designed for locking or unlocking the door, and DI water or detergent may enter into the inside structure of the door in the cleaning process, wherein the inside structure is hardly dried up after cleaning process. The prior method is to provide high pressure air flow to the recess regions at two sides of the door such that detergent or DI water can be prevented from entering inside the door through the two recess regions in the cleaning process.

[0060] The recess regions appeared at two sides of the door for current FOUP include latch structures, such that the door can be engaged with the body of FOUP completely. Except the two recess regions and the outside surface of the door, most of the exterior structure of the FOUP will not have recess or hole, neither door or body of the FOUP, due to the detergent residue issue after cleaning. This complex design will incur higher cost to the cleaning system.

[0061] In the present invention, DI(De-ionized) water is used for cleaning the FOUP instead of detergent to prevent from detergent residing at the recess regions of the FOUP. In the current semiconductor process node, especially for less than 10 nanometer process node, it would be better to clean container or FOUP by using DI water only to avoid unnecessary issue from detergent. When DI water is purged with high pressure, most particles or contamination can be removed.

[0062] In the present invention, it is an important purpose to prevent from unnecessary particles and DI water entering the recess regions of the door. One method is to provide a shelter such that DI water can’t enter the recess regions, and another method is to provide a positive pressure environment to the outside surface of the door such that DI water in the cleaning chamber cannot enter the recess regions.

[0063] When only Di water is used, inclined purge will be better than vertical purge to take contamination or particles away from surfaces of the FOUP. Thus, in the present invention, an environment with inclined purge is provided.

[0064] In the present invention, a method is provided to clean outside surface of the door and also to prevent from DI water entering inside structure of the door. The outside surface of the door faces up, and a gas flow from upside down to the external or outside surface of the door is provided. Gas can be nitrogen or CDA(Clean dry air) with high pressure.

[0065] The DI water is inclined purged from bottom upward to the internal or inside surface of the door, while gas flow can be provided also with similar or the same manner. DI water and gas flow can be purged alternatively or simultaneously. The alternative times and purge duration can be optimized as suitable recipes according to cleaning practices.

[0066] A shelter with a square opening is provided below the door such that DI water can be prevented from purging to or entering the recess or hole regions on the two sides of the door. The shelter can be conical which will induce less air turbulence inside the cleaning chamber when the door, shelter, and body are rotating in the cleaning process. If the turbulence issue is not critical, the shelter can be other shapes.

[0067] Internal and external sides of the FOUP body is cleaned by using similar manner, inclined purge by using DI water and gas flow alternatively or simultaneously.

[0068] Gas flow can also be provided while drying step is running after cleaning process.

[0069] The purpose of the present invention is to provide an environment that DI water can be prevented from entering into inside structure of the door. Thus, there is no need to design such a complex structure to block recess or hole regions with gas flow as shown in the prior art. The system thus can be simplified with lower cost. [0070] In this invention, a cleaning system includes a shelter with a square opening for engaging the internal side of the door. In a preferred embodiment, the shelter can be conical and water-proof. The system includes a main nuzzle for purging a main gas flow upside down to the external side of the door. The main gas flow provides a positive pressure environment to the door such that DI water can be prevented from entering recess regions of the door. The system includes a first nuzzle for spraying a first DI water beam with an angle to the internal side of the door, and for purging a first gas flow with an angle to the internal side of the door. This first nuzzle may include two pipes which provide the first DI water beam and the first gas flow respectively and independently, or may include one pipe which provides the first DI water beam and the first gas flow alternatively. The system includes a second nuzzle for spraying a second DI water beam with an angle inside the container, and for purging a second gas flow with an angle inside the container. This second nuzzle may include two pipes which provide the second DI water beam and the second gas flow respectively and independently, or may include one pipe which provides the second DI water beam and the second gas flow alternatively. The system includes a frame for supporting the container and the shelter. The FOUP body is placed and supported by the frame and preferred to be fixed by the shelter. The shelter is placed above the FOUP body and fixed by the frame. The FOUP door is engaged with and on the shelter. The system includes a motor, engaged with the frame, for rotating the FOUP and the shelter in the cleaning process. The system includes a heater for heating the FOUP after cleaning process. The system includes a cleaning chamber such that the frame is configured inside the chamber.

[0071] In this invention, a cleaning method includes a step of providing a frame inside a cleaning chamber which is configured by several rods. The cleaning method includes a step of opening a door of the container and placing the container body inside the frame with an opening downward. The cleaning method includes a step of configuring a conical shelter, with a square opening, fixed by the frame and on the container body. The method includes a step of placing the door on the shelter with the internal side engaging the square opening, and the external side upward. The method includes a step of purging a main gas flow from upside down to the external side of the door. The method includes a step of spraying a first DI water beam to the internal side of the door with an angle, and a step of purging a first gas flow to the internal side of the door with an angle. The method includes a step of spraying a second DI water beam inside the container body, and a step of purging a second gas flow inside the container body. The method includes a step of spinning the container body and the door. The method includes a step of heating the container body and the door then. [0072] Accordingly, while example embodiments of the invention are capable of various modifications and alternative forms, embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that there is no intent to limit example embodiments of the invention to the particular forms disclosed, but on the contrary, example embodiments of the invention are to cover all modifications, equivalents, and alternatives falling within the scope of the invention.

[0073] Please refer to Figure 1A and Figure IB, wherein a FOUP 100 which includes a body 102 and a door 110 is shown in top view. In this embodiment, the sample 10 is a wafer, and shape of the FOUP 100 fit to the wafer. If the sample is a mask or reticle, the shape of the FOUP 100 is cubical. The internal side or inner surface 112 of the door 110 with body 102 together provides an ultrahigh clean environment. The external side or outside surface 114 of the door 112 opposites to the inner surface 112. There is an inside space between the internal side 112 and external side 114 for latch structures. There are four recess regions 116 at upside and down side of the door 110, and only two recess regions 116 shown in Figure IB.

[0074] In Figure 1C, inside structures of the door 110 is shown. Please refer to Figure 1C, wherein four latch plates 120 can extend through the four recess regions 116 to engage with the body 120 to achieve ultrahigh clean environment and to isolate with outside environment. Two latch hubs 122 engaged with the four latch plates 120 and may move the four latch plates 120. In Figure ID, external side 114 of the door 110 is shown. There are two holes 118 to fit two latch hubs 122 inside the door 110 to control the positions of the latch plate 120.

[0075] In the prior art as shown in the Rebstock, the external side 114 of the door 110 is not cleaned to prevent from detergent or liquid entering inside of the door 110 through the holes 118. Further, there may be some other holes distributed on the external side 114(not shown in the Figure ID), because the external side 114 of the door 110 is a plate such that the door 110 is assembled via these holes. Hence, only internal side 112 of the door 110 is cleaned in the prior art.

[0076] In Figure 2, a side view of a frame 200 is shown. Please refer to Figure 2, wherein a frame 200 includes at least eight rods 202 such that body 120 of the FOUP 100 can be placed. The rods 202 can be made by metal for providing a stable support. The frame 200 per se can be rotated 220 by engaging with a rotation axis 224 and a motor 222.

[0077] In Figure 3, there is a conical hat shelter 300, between the body 102 and the door 110, fixed on four rods 202 of the frame 200, wherein the external side 114 of the door 110 faces up, and the opening of the FOUP body 102 faces downward. Fringes of the shelter 300 has an angle Q relative to a rod 202, wherein Q can be ranged from 0° to 180°, preferred from 5° to 175°, and more preferred from 11° to 20°. Or, an angle between the fringe of the shelter 300 and the door 110 could be ±90°, preferred ±85°, and more preferred between 70° to 79°.

[0078] In Figure 4, a top view of the shelter 300 is shown. The shelter 300 has a square opening 302 with a dimension smaller than the door 110. The dimension of the square opening 302 would be preferred to equal to opening of the body 102, such that internal side 114 of the door 110 can be engaged with the square opening 302 of the shelter 300. Material of the shelter 300 is water-proof, which can be metal, acrylic, PP(Polypropylene), PE(Poly ethylene), PET(Polyethylene terephthalate), PVDF(Polyvinylidene fluoride), PEEK(Polyether ether ketone), PTFE(Polytetrafluoroethylene), PFA(Perfluoro alkoxy alkane), rubber, or engineering plastic. Four through holes 304 in the shelter 300 could let four rods 202 pass through such that the shelter 300 can be fixed to the frame 200. The shape of the shelter fringe in Figure 3 is a circle, because the shelter 300 in the cleaning process will spin or rotate. This profile will cause least air turbulence while a gas flow from upside down to the shelter 300.

[0079] Sectional line in the fringe of the shelter 300, in one embodiment, can be a straight line as shown in Figure 3. However, please refer to Figure 5, wherein sectional line in the fringe of the shelter 300 can be a curve line 310. In another embodiment, the sectional line can be polyline although not shown in Figure 5.

[0080] Please refer to Figure 6, wherein a system for cleaning FOUP is shown. In order to clearly show the cleaning system, the frame 200 is not shown. In Figure 6, opening of the body 102 faces down, and the body is supported and fixed by the frame 200. The shelter 300 covers the body 102 with square opening 302 engaging with the door 110, and is supported and fixed by the frame 200. The external side of the door 102 faces upside. A main nuzzle 400 above the door 110 provides a main gas flow to clean the external side of the door 110. A first nuzzle 410 can spray or purge a DI water beam and purge a gas flow to clean the internal side of the door 110. A second nuzzle 440 can spray or purge a DI water beam and purge a gas flow to the internal side of the body 102. The two nuzzles 410 and 440 can provide DI water beams and gas flows alternatively or simultaneously. The alternative times and purging duration can be optimized according to cleaning practice to determine recipes. The gas purged by the main nuzzle 400, the first nuzzle 410, and the second nuzzle 440 can be nitrogen or CDA. All the frame 200, FOUP body 102, shelter 300, door 110, main nuzzle 400, first nuzzle 410, and second nuzzle 440 are inside the cleaning chamber 500.

[0081] Heater 510 can be configured outside or inside the cleaning chamber 500 for providing drying step after the cleaning process. The heater 510 can be configure outside the cleaning chamber 500 if the heater 510 can provide enough drying efficiency. The heater 510 can be configured inside the cleaning chamber 500 if the heater 510 per se is water-proof.

[0082] Please refer to Figure 7, wherein another embodiment of the clean system is shown. An individual first nuzzle 420 provides a DI water beam and an individual second nuzzle 430 provides a gas flow for cleaning the internal side of the door 110. An individual third nuzzle 450 provides DI water beam and an individual fourth nuzzle 460 provides a gas flow for cleaning inside of the body 102. The heater 510 is configured inside the cleaning chamber 500.

[0083] Please refer to Figure 8, wherein a schematic illustration of cleaning the FOUP is shown. DI water beam 412 and gas flow 418 are provided for cleaning internal side of the door 110 and outside of the body 102. DI water 422 and gas flow 428 are provided for cleaning inside of the body 102. Inclined purge will take contaminations or particles away from surfaces of the door and body easier. The main nuzzle 400 provides a gas flow 402 from upside to the external side of the door 102 and along with the shape of the shelter 300 down to bottom of the cleaning chamber 500. The gas flow 402 provides a positive pressure environment such that DI water 412 can not entering the inside of the door 110. The doorl 10, shelter 300 and body 102 can be rotated 220 during the cleaning process. The door 110 and body 102 are then dried up after cleaning process. The gas flows 418 and 428 can be provided while drying.

[0084] According to the embodiments described above, the present invention thus provides a method for cleaning a door of a container, which comprises steps of providing a conical shelter with an opening, placing the door on the shelter with the opening engaging with an internal side of the door downward, and spraying a DI water beam under the shelter to the internal side of the door with an angle, wherein the shelter prevents the DI water beam from contaminating an inside structure of the door.

[0085] The method according to the present invention, the shelter is waterproof.

[0086] The method according to the present invention, the shelter has a straight section line, a curved section line, or a poly section line. [0087] The method according to the present invention further comprises a step of providing a positive pressure environment by purging a gas flow to an external side of the door, wherein the external side faces upward, before said spraying step.

[0088] The method according to the present invention, the gas flow is a nitrogen flow or a clean dry air flow.

[0089] The present invention further provides a method for cleaning a door of a container, which comprises steps of providing a positive pressure environment by purging a gas flow to an external side of the door, wherein the external side faces at a first direction, and spraying a DI water beam from a second direction, opposite to the first direction, to an internal side of the door with an angle, wherein the gas flow along the door prevents the DI water beam from contaminating an inside structure of the door.

[0090] The method according to the present invention, the gas flow is a nitrogen flow, or a clean dry air flow.

[0091] The present invention further provides a method for cleaning a container, which comprises steps of separating a door from the container; placing the container in a chamber with an opening thereof downward; configuring a conical shelter with a square opening on the container; placing the door on the shelter with an external side of the container upward, and an internal side of the door engaging with the square opening; purging a main gas flow upside down to the external side of the door; spraying a first DI water beam to the internal side with a first angle; purging a first declined gas flow to the internal side with a second angle; spraying a second DI water beam inside the container with a third angle; purging a second declined gas flow inside the contained with a fourth angle; spinning the door and the container; and drying the container and the door.

[0092] The method according to the present invention, the shelter is waterproof.

[0093] The method according to the present invention, the shelter has a straight section line, a curved section line, or a poly section line.

[0094] The method according to the present invention, the main gas flow, the first declined gas flow, and the second declined gas flow are a nitrogen flow or a clean dry air flow.

[0095] The method according to the present invention, an angle between a fringe of the shelter and the door is within ±85°. [0096] The method according to the present invention, said step of purging the first DI water beam and said step of purging a first declined gas flow are alternatively, and said step of purging the second DI water beam and said step of purging a second declined gas flow are alternatively.

[0097] The method according to the present invention, said step of purging the first DI water beam and said step of purging a first declined gas flow are alternatively, and said step of purging the second DI water beam and said step of purging a second declined gas flow are alternatively.

[0098] The present invention further provides a system for cleaning a container, which comprises a conical shelter with an opening for engaging an internal side of a door of the container; a main nuzzle for purging a main gas flow upside down to an external side of the door; a first nuzzle for spraying a first DI water beam to the internal side with a first angle, and for purging a first declined gas flow to the internal side with a second angle; a second nuzzle for spraying a second DI water beam to an inside surface of the contained with a third angle, and for purging a second declined gas flow to the inside surface of the container with a fourth angle; a motor for rotating the container and the door; and a heater for drying the container and the door.

[0099] The system according to the present invention, the shelter is waterproof.

[00100] The system according to the present invention, an angle between a fringe of the shelter and the door is within ±85°.

[00101] The system according to the present invention, the main gas flow, the first declined gas flow, and the second declined gas flow are a nitrogen flow or a clean dry air flow.

[00102] The system according to the present invention further comprises a frame, for the container to be placed, engaging with the motor and the shelter.

[00103] The system according to the present invention further comprises a cleaning chamber for enclosing said frame, said main nuzzle, said first nuzzle, said second nuzzle, and said shelter.

[00104] The system according to the present invention, the cleaning chamber encloses said heater.

[00105] In this invention, the system for cleaning FOUP occupies a relative small footprint compared to the commercial available solution, because the FOUP door and FOUP body are stacked. [00106] In this invention, the external side of the door can be cleaned by gas flow, which can’t be approached by the prior solution.

[00107] In this invention, the cleaning system has simple structure compared to the commercially available solution.

[00108] Although the present invention has been described in accordance with the embodiments shown, one of ordinary skill in the art will readily recognize that there could be variations to the embodiments and those variations would be within the spirit and scope of the present invention. Accordingly, many modifications may be made by one of ordinary skill in the art without departing from the spirit and scope of the appended claims.

Claims

INVENTION:

1. A method for cleaning a door of a container, comprising: providing a conical shelter with an opening; placing the door on the shelter with the opening engaging with an internal side of the door downward; and spraying a DI water beam under the shelter to the internal side of the door with an angle, wherein the shelter prevents the DI water beam from contaminating an inside structure of the door.

2. The method according to claim 1, wherein the shelter is waterproof.

3. The method according to claim 2, wherein the shelter has a straight section line, a curved section line, or a poly section line.

4. The method according to claim 1, further comprising a step of providing a positive pressure environment by purging a gas flow to an external side of the door, wherein the external side faces upward, before said spraying step.

5. The method according to claim 4, wherein the gas flow is a nitrogen flow or a clean dry air flow.

6. A method for cleaning a door of a container, comprising: providing a positive pressure environment by purging a gas flow to an external side of the door, wherein the external side faces at a first direction; and spraying a DI water beam from a second direction, opposite to the first direction, to an internal side of the door with an angle, wherein the gas flow along the door prevents the DI water beam from contaminating an inside structure of the door.

7. The method according to claim 6, wherein the gas flow is a nitrogen flow, or a clean dry air flow.

8. A method for cleaning a container, comprising: separating a door from the container; placing the container in a chamber with an opening thereof downward; configuring a canonical shelter with a square opening on the container; placing the door on the shelter with an external side of the container upward, and an internal side of the door engaging with the square opening; purging a main gas flow upside down to the external side of the door; spraying a first DI water beam to the internal side with a first angle; purging a first declined gas flow to the internal side with a second angle; spraying a second DI water beam inside the container with a third angle; purging a second declined gas flow inside the contained with a fourth angle; spinning the door and the container; and drying the container and the door.

9. The method according to claim 8, wherein the shelter is waterproof.

10. The method according to claim 9, wherein the shelter has a straight section line, a curved section line, or a poly section line.

11. The method according to claim 10, wherein the main gas flow, the first declined gas flow, and the second declined gas flow are a nitrogen flow or a clean dry air flow.

12. The method according to claim 11, wherein an angle between an fringe of the shelter and the door is within ±85°.

13. The method according to claim 12, wherein said step of purging the first DI water beam and said step of purging a first declined gas flow are alternatively, and said step of purging the second DI water beam and said step of purging a second declined gas flow are alternatively.

14. A system for cleaning a container, comprising: a conical shelter with an opening for engaging an internal side of a door of the container; a main nuzzle for purging a main gas flow upside down to an external side of the door; a first nuzzle for spraying a first DI water beam to the internal side with a first angle, and for purging a first declined gas flow to the internal side with a second angle; a second nuzzle for spraying a second DI water beam to an inside surface of the contained with a third angle, and for purging a second declined gas flow to the inside surface of the container with a fourth angle; a motor for rotating the container and the door; and a heater for drying the container and the door.

15. The system according to claim 14, wherein the shelter is waterproof.

16. The system according to claim 15, wherein an angle between an fringe of the shelter and the door is within ±85°

17. The system according to claim 16, wherein the main gas flow, the first declined gas flow, and the second declined gas flow are a nitrogen flow or a clean dry air flow.

18. The system according to claim 17, further comprising a frame, for the container to be placed, engaging with the motor and the shelter.

19. The system according to claim 18, further comprising a cleaning chamber for enclosing said frame, said main nuzzle, said first nuzzle, said second nuzzle, and said shelter.

20. The system according to claim 19, wherein the cleaning chamber encloses said heater.