Fluid distribution system
The present invention provides a method and apparatus for bulk fluid distribution. In particular, the invention provides a method and apparatus for distributing fluids in a semiconductor manufacturing plant (e.g. a 300 mm fab). The invention meets the performance and uptime requirements of semiconductor manufacturers including increased capacity and pressure control as compared to known fluid distribution systems, and can satisfy the requirements of “no single point failures” and “no planned downtime.”
This application claims priority from U.S. Provisional Patent Application Ser. No. 60/795,730 filed Apr. 28, 2006.
FIELD OF THE INVENTIONThe present invention relates to an apparatus and method for distributing a fluid to a point of use. More specifically, the present invention provides an apparatus, having no single point failures or planned downtime, and a method for distributing a fluid to a semiconductor process tool for semiconductor processing.
BACKGROUND OF THE INVENTIONThe manufacture of semiconductor (i.e. integrated circuit) devices is a complex process involving hundreds of process steps. Each step requires optimal conditions to produce a high yield of the devices. In addition, many process steps require fluids to inter alia etch, expose, coat, and polish materials deposited on the surfaces of the devices during manufacturing. When high purity fluids (e.g. hydrofluoric acid, sulfuric acid, hydrogen peroxide, ammonium hydroxide and isopropyl alcohol) are used during the manufacturing process, the fluids must be substantially free of particulate and metal contaminants to prevent defects in the finished devices. When chemical-mechanical polishing slurries (e.g. Semi-Sperse®-12, iCue® 5001, Klebosol® 1501 and Cab-O-Sperse® SC-112) are used, the slurries must be free from large particles capable of scratching the surfaces of the devices and causing defects. Moreover, during manufacturing there must be a stable and sufficient supply of the fluids to the process tools to avoid process fluctuations and manufacturing downtime.
Since their introduction to the semiconductor market, bulk fluid distribution systems have played an important role in semiconductor manufacturing processes. Prior to the use of fluid distribution systems, process fluids were stored and transported to the process tools in plastic or glass bottles. This method involved many hazards in transportation and use such as broken bottles, chemical exposure to operators, and spilling or splashing when pouring the fluids into baths or other containers. In addition, there were several opportunities for the fluids to become contaminated through exposure to the atmosphere and contact with objects (e.g. operator gloves). Fluid distribution systems, such as the Model 1500 manufactured by the Chemical Management Division of BOC Edwards™, Inc., were developed to eliminate these hazards and contamination issues and to help automate the process of replenishing fluids in the manufacturing process. Notably, the Model 1500 has been used by semiconductor manufacturers for over a decade.
A representation of a typical fluid distribution system used in semiconductor manufacturing processes is shown in
The components of system 100 are enclosed in a stainless steel or polymer cabinet 125 and the system is substantially constructed of inert wetted materials to minimize particulate and metal contamination of the process fluids. While the bulk fluid distribution system 100 of
The fluid distribution system of
As a result of such limitations to existing designs, many semiconductor manufacturers require two fluid distribution systems per fluid stream in order to ensure complete redundancy. This solution is costly and inefficient with regard to space utilization. Some fluid distribution system designs address these issues in different ways. For example, one design provides redundant pump engines with independently serviceable cabinets. Other systems address redundancy and uptime by using dual pump engines whereby the system has the capability of switching from the on-line pump to the off-line pump when the on-line pump fails. These designs allow for limited maintenance of systems while they are operating. However, the dual pump engines are not equivalent—one engine is smaller than the other and complete serviceability and maintenance cannot be performed without system shutdown. Another design also provides redundant pumps, but in a shared cabinet. The filters are not redundant and the system has less redundancy options for maintenance and serviceability as compared to the first mentioned design. Yet another design offers considerable redundancy and good serviceability, but is costly due to excessive amounts of isolation in the system.
Thus, there is a need for a bulk fluid distribution system that substantially or completely eliminates single point failures and the impact of product maintenance shutdowns (i.e. “planned downtime”). In addition, there is a further need for a bulk fluid distribution system that is modular and has a smaller footprint as compared to the footprint of two distribution systems such as system 100 shown in
A fluid distribution system for supplying fluid to a point of use comprising a fluid source; a first engine adapted to receive fluid from the fluid source and to distribute fluid to the point of use; and a second engine identical to the first engine, the second engine being adapted to receive fluid from the fluid source and to distribute fluid to the point of use; wherein the fluid distribution system does not have any single point failures.
A method of distributing fluid to a point of use comprising distributing fluid to the point of use with a first engine; filtering fluid in a day tank with a second engine; and filtering fluid in a supply drum with a third engine; wherein each of the first, second and third engines is adapted to perform the steps of distributing fluid to the point of use, filtering fluid in the day tank and filtering fluid in the supply drum.
The present invention provides a method and apparatus for bulk fluid distribution. In particular, the invention provides a method and apparatus for distributing fluids in a semiconductor manufacturing plant (e.g. a 300 mm fab). The invention meets the performance and uptime requirements of semiconductor manufacturers including increased capacity and pressure control as compared to known fluid distribution systems, and can satisfy the requirements of “no single point failures” and “no planned downtime.”
An embodiment of a bulk fluid distribution system according to the present invention is shown in
In one embodiment, facility supply lines 215, including compressed dry air 215a, nitrogen 215b, deionized water 215c, city water 215d and exhaust 215e, and fluid dispense line 217 flow into and out of the main module 207. In another embodiment, the facility supply lines 215 may also flow into and out of each module 201, 203, 205, 209 and 211.
Fluid supply lines 219a and 219b are connected to the source management module 209 which distributes the source fluid to the main module 207. In one embodiment, each of the engines 201, 203 and 205 receives the source fluid from the main module 207 through, for example, bulk-heads or pass-throughs in the module cabinets. In another embodiment, the engine modules 201, 203 and 205 may receive the source fluid directly from the source management module 209.
The plumbing and instrumentation and operation of each module will be described separately with reference to
A schematic diagram of the main module 207 is shown in
As mentioned above, the engines may all be identical so that each can perform the same operations thereby providing redundancy and serviceability and eliminating or substantially reducing single point failures and planned downtime. A single point failure occurs where a component in the fluid distribution system fails causing the entire system to shutdown and stop distributing fluid to the point of use. The failed component may be a valve in the distribution loop that mechanically prevents fluid flow or may be a valve in the system exhaust that prevents safely exhausting the cabinet. Planned downtime refers to the periodic maintenance schedule of components in the system; in prior art systems, if certain components must be replaced or serviced, the entire system must be shutdown. A system having no planned downtime is one where periodic maintenance may be performed on a system component without disrupting operation of the system, in particular, fluid distribution to the point of use.
Notably, all engines are capable of receiving fluid from the source drums through line 220, the main module 207, or from the day tank module 211. Furthermore, all of the engines dispense the fluid through a filter or a filter bank (i.e. two to four filters in parallel) and back to either the drums 213 or day tank module 211 or to the points of use 217. In addition, each engine is capable of distributing fluid to the points of use, polishing the fluid in the day tank (by filtering), polishing the fluid in the drums (by filtering), drum switching or any combination thereof.
A second embodiment of the engine 201, 203 or 205 of the present invention is shown in
A third embodiment of the engine 201, 203 or 205 of the present invention is shown in
A fourth embodiment of the engine 201, 203 or 205 of the present invention is a pressure-vacuum vessel engine. The pressure-vacuum vessel engine includes two pressure-vacuum vessels 801, 802. Each vessel 801, 802 is equipped with at least two fluid level sensors 803, 804, 805, 806 such as capacitive, optical or digital sensors, or load cells. The sensors 803, 804, 805, 806 monitor the fluid level in the vessels 801, 802.
During a fill cycle, a vacuum-generating device 807, 808 (e.g. an aspirator or venturi) creates a vacuum in the vessel to draw in the fluid. When the vacuum is operated on a vessel, any gas in the vessel flows to an exhaust 215e as the fluid from either the source line 220, the main module 207 or the day tank module 211 is drawn into the vessel. When the fluid level reaches a predetermined high level, the vacuum stops.
During a dispense cycle, an inert gas, such as nitrogen, flows through a “slave” regulator 809, 810 and into the dispensing vessel 801, 802. The vessel 801, 802 is initially pressurized to a predetermined pressure and then the fluid under the force of the inert gas pressure flows through the filter 811 and to the points of use 217, or back to the drums 213 or the day tank module 211. The vessel 801, 802 dispenses the fluid until it reaches a predetermined low fluid level at which point the fill cycle begins again.
During operation, the vessels 801, 802 alternate between fill and dispense cycles such that when one vessel is filling, the other vessel is dispensing. Notably, the vacuum-generating device 807, 808 is configured so that the vessels 801, 802 fill faster than they dispense to provide a continuous flow of fluid to the points of use or other areas in the system 211, 213.
Each engine 201, 203, 205 is capable of distributing fluid to the points of use, polishing the fluid in the day tank 901 (by filtering), polishing the fluid in the drums 213 (by filtering), drum switching or any combination thereof. When an engine distributes fluid to the points of use 217, it dispenses the fluid into either a global distribution loop that recirculates back to the fluid distribution system or to a dead-headed dispense line. Typically several semiconductor tools are teed into the global distribution loop or dispense line and demand fluid from these lines on a periodic or continuous basis. When fluid in the day tank 901 is polished, the engine 201, 203, 205 draws the fluid from the day tank 901 in the day tank module 211 and dispenses the fluid through a filter 811 and back into the day tank 901. The fluid is recirculated through the filter for a predetermined period of time (i.e. about 5-45 minutes). Similarly, the fluid in one of the drums 213 is polished when the engine 201, 203, 205 draws fluid from the drum and dispenses the fluid through the filter 811 and back into the drum. The fluid is recirculated through the filter and back to the drum for a predetermined period of time (i.e. about 5-45 minutes). The engine 201, 203, 205 can also send a signal to the controller 401 to effectuate drum switching. The engine 201, 203, 205 will send the signal when it detects that there is no fluid in the on-line drum. The controller 401 then closes the valve (e.g. 301) in the source management module 209 connected to the on-line drum and opens the valve (e.g. 303) connected to the off-line drum so as to switch between the drums.
Another important feature of the fluid distribution system according to the present invention is the configuration of the various modules in order to reduce floor space as compared to known fluid distribution systems. Embodiments of possible floor space configurations are shown in
The present invention as described above and shown in the embodiments of
Claims
1. A fluid distribution system for supplying fluid to a point of use comprising:
- a fluid source;
- a first engine adapted to receive fluid from the fluid source and to distribute fluid to the point of use; and
- a second engine identical to the first engine, the second engine being adapted to receive fluid from the fluid source and to distribute fluid to the point of use;
- wherein the fluid distribution system does not have any single point failures.
2. The fluid distribution system of claim 1 having no planned downtime wherein the system is adapted to distribute fluid to the point of use while maintenance is performed on any component of the system.
3. The fluid distribution system of claim 1 further comprising a third engine identical to the first and second engines wherein the third engine is adapted to receive fluid from the fluid source and to distribute fluid to the point of use.
4. The fluid distribution system of claim 1 wherein the first and second engines comprise a pump and a pressure vessel.
5. The fluid distribution system of claim 4 wherein the pressure vessel comprises a level sensor.
6. The fluid distribution system of claim 4 wherein the pressure vessel comprises a load cell.
7. The fluid distribution system of claim 1 wherein the first and second engines comprise a positive displacement pump and a pulse dampener.
8. The fluid distribution system of claim 1 wherein the first and second engines comprise a centrifugal pump.
9. The fluid distribution system of claim 1 wherein the first and second engines comprise a pressure vacuum vessel.
10. The fluid distribution system of claim 9 wherein each of the pressure vacuum vessels comprises a sensor.
11. The fluid distribution system of claim 9 wherein each of the pressure vacuum vessels comprises a load cell.
12. The fluid distribution system of claim 1 wherein the point of use is a semiconductor process tool.
13. A fluid distribution system comprising:
- a main module;
- a day tank module;
- a fluid source;
- a point of use;
- a first engine adapted to receive fluid from each of the main module, the day tank module and the fluid source and adapted to dispense fluid to each of the day tank module, the fluid source and the point of use; and
- a second engine adapted to receive fluid from each of the main module, the day tank module and the fluid source and adapted to dispense fluid to each of the day tank module, the fluid source and the point of use;
- wherein the fluid distribution system does not have any single point failures.
14. The fluid distribution system of claim 13 having no planned downtime wherein the system is adapted to distribute fluid to the point of use while maintenance is performed on any component of the system.
15. The fluid distribution system of claim 13 further comprising a third engine adapted to receive fluid from each of the main module, the day tank module and the fluid source and adapted to dispense fluid to each of the day tank module, the fluid source and the point of use.
16. The fluid distribution system of claim 13 further comprising a central processing unit having an input-output module connected to each of the first and second engines.
17. The fluid distribution system of claim 13 further comprising a plurality of central processing units wherein each central processing unit comprises an input-output module connected to each of the first and second engines.
18. The fluid distribution system of claim 13 wherein the first and second engines comprise a pump and a pressure vessel.
19. The fluid distribution system of claim 18 wherein the pressure vessel comprises a level sensor.
20. The fluid distribution system of claim 18 wherein the pressure vessel comprises a load cell.
21. The fluid distribution system of claim 13 wherein the first and second engines comprise a positive displacement pump and a pulse dampener.
22. The fluid distribution system of claim 13 wherein the first and second engines comprise a centrifugal pump.
23. The fluid distribution system of claim 13 wherein the first and second engines comprise a pressure vacuum vessel.
24. The fluid distribution system of claim 23 wherein each of the pressure vacuum vessels comprises a sensor.
25. The fluid distribution system of claim 23 wherein each of the pressure vacuum vessels comprises a load cell.
26. A method of distributing fluid to a point of use comprising:
- distributing fluid to the point of use with a first engine;
- filtering fluid in a day tank with a second engine; and
- filtering fluid in a supply drum with a third engine;
- wherein each of the first, second and third engines is adapted to perform the steps of distributing fluid to the point of use, filtering fluid in the day tank and filtering fluid in the supply drum.
27. The method of claim 26 wherein in the event of failure of a component in the first engine, the second engine or the third engine is adapted to distribute the fluid to the point of use.
28. The method of claim 26 further comprising the step of performing maintenance on a component of the fluid distribution system without requiring any planned downtime.
Type: Application
Filed: Apr 23, 2007
Publication Date: Nov 1, 2007
Inventor: David Paul Edwards (Waconia, MN)
Application Number: 11/788,891