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Patent US5980368 - Polishing tool having a sealed fluid chamber for support of polishing pad - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsA polishing tool uses a seal cavity containing a fluid that supports polishing pads against an object being polished. In one embodiment, the boundaries of the cavity include a support structure, a portion of a polishing material, and a seal between the support structure and the polishing material. The...http://www.google.com/patents/US5980368?utm_source=gb-gplus-sharePatent US5980368 - Polishing tool having a sealed fluid chamber for support of polishing padAdvanced Patent SearchPublication numberUS5980368 APublication typeGrantApplication numberUS 08/964,774Publication dateNov 9, 1999Filing dateNov 5, 1997Priority dateNov 5, 1997Fee statusLapsedAlso published asEP0920956A2, EP0920956A3Publication number08964774, 964774, US 5980368 A, US 5980368A, US-A-5980368, US5980368 A, US5980368AInventorsShou-sung Chang, Shu-Hsin Kao, David E. WeldonOriginal AssigneeAplex GroupExport CitationBiBTeX, EndNote, RefManPatent Citations (7), Referenced by (36), Classifications (18), Legal Events (9) External Links: USPTO, USPTO Assignment, EspacenetPolishing tool having a sealed fluid chamber for support of polishing pad
US 5980368 AAbstract
A polishing tool uses a seal cavity containing a fluid that supports polishing pads against an object being polished. In one embodiment, the boundaries of the cavity include a support structure, a portion of a polishing material, and a seal between the support structure and the polishing material. The polishing material moves relative to the support structure and seal. A variety of seal configuration can maintain the fluid within the cavity. One seal includes an o-ring that the force of a spring, a magnet, or air pressure presses against the polishing material. A gas flow from outside the cavity or from an inlet inside the cavity can form a gas pocket in the cavity, adjacent the o-ring, to prevent leakage of the fluid past the o-ring. Another seal is formed by an aerostatic bearing. The fluid pressure in the cavity can be varied temporally to create vibrations in the polishing material to enhance polishing performance or can be varied spatially to change the pressure profile. One embodiment of the invention includes one or more fluid inlet/outlets to the cavity, one or more pressure regulators, and a controller that operates the pressure regulators to control the pressure in the cavity. In polishers with or without a sealed fluid cavity, the support structure can include actuators that control the orientation of the support structure relative to polishing material. Sensors and a feedback control system positions the support structure for polishing.
1. A support for a polishing tool, comprising:a compliant polishing material; a support structure that includes a depression disposed adjacent the compliant polishing material; a seal that surrounds the depression, the seal extending from the support structure to the compliant polishing material; and fluid enclosed in a cavity bounded by the depression, the seal, and a portion of the compliant polishing material, wherein a pressure of the fluid supports the polishing material. 2. The support of claim 1, wherein the fluid is substantially static.
3. The support of claim 1, wherein the seal comprises an o-ring that surrounds the cavity.
4. The support of claim 3, wherein the seal further comprises a gas pocket adjacent the o-ring, wherein the gas pocket prevents the fluid from leaking past the o-ring.
5. The support of claim 4, further comprising a gas inlet adjacent the o-ring, wherein gas in the gas pocket is introduced via the gas inlet.
6. The support of claim 4, further comprising a source of a gas flow from outside the cavity toward the o-ring, wherein gas in the gas pocket is introduced from the gas flow via leakage past the o-ring.
7. The support of claim 3, further comprising a spring mechanism that presses the o-ring against the compliant polishing material.
8. The support of claim 3, further comprising a magnet that presses the o-ring against the compliant polishing material by magnetic force.
9. The support of claim 8, wherein the compliant polishing material contains iron and the magnet that presses the o-ring against the compliant polishing material by the magnetic force cause by attraction between the magnet and the compliant polishing material.
10. The support of claim 1, further comprising:a fluid supply; a fluid inlet/outlet to the cavity; a pressure regulator coupled to the fluid supply and the inlet/outlet; and a controller coupled to the pressure regulator, wherein the controller operates the pressure regulator to vary fluid pressure in the cavity. 11. The support of claim 10, further comprising:a plurality of fluid inlet/outlets to the cavity; and a plurality of pressure regulators, each pressure regulator being coupled to an associated inlet/outlet. 12. The support of claim 1, wherein the seal comprises an aerostatic bearing.
13. The support of claim 12, further comprising an adjustable mounting that allows tilting of the support structure to match orientation with the polishing material.
14. The support of claim 13, further comprising: sensors that measure the relative orientation of the polishing material and the support structure;actuators capable of adjusting the orientation of the support structure; and a control system coupled to the sensors and the actuators. 15. A support for a polishing material in a polisher, comprising:a support structure; sensors that measure the relative orientation of the polishing material and the support structure; actuators capable of adjusting the orientation of the support structure; and a control system coupled to the sensors and the actuators, wherein the control system operates the actuators to keep the support structure oriented for polishing. 16. The support structure of claim 15, wherein the support structure comprises:a cavity for containing a sealed fluid pocket that supports the polishing material; and an aerostatic bearing that surrounds the cavity and is disposed adjacent the polishing material. 17. The support structure of claim 16, wherein the sensors comprise pressure sensors disposed in the cavity for measuring local pressure in the fluid pocket.
18. A method for polishing an object, comprising:placing the object in contact with a polishing material; supporting the polishing material using a sealed fluid pocket having a plurality of inlet/outlets; applying fluid at a first pressure to a first of the inlet/outlets and a second pressure to a second of the inlet/outlets, wherein pressures to the inlet/outlets control a support pressure profile of the fluid pocket; and moving the polishing material relative to the object while the fluid pocket supports the polishing material. 19. The method of claim 18, wherein the pressure profile provides a higher pressure where material removal rate from the object would otherwise be lower during polishing.
20. The method of claim 19, wherein the support pressure profile provides a higher pressure under a low spot in the polishing material.
21. The method of claim 19, wherein the support pressure profile provides a higher pressure under an area where relative velocity between the polishing material and the object is lower.
22. The method of claim 19, wherein the object is a wafer.
Chemical mechanical polishing (CMP) in semiconductor processing removes the highest points from the surface of a wafer to polish the surface. CMP operations are performed on unprocessed and partially processed wafers. A typical unprocessed wafer is crystalline silicon or another semiconductor material that is formed into a nearly circular wafer. A typical processed or partially processed wafer when ready for polishing has a top layer of a dielectric material such as glass, silicon dioxide, or silicon nitride over one or more patterned layers that create local topological features on the order of about 1 μm in height on the wafer's surface. Polishing smoothes the local features so that ideally the surface of the wafer is flat or planarized over an area the size of a die formed on the wafer. Currently, polishing is sought that locally planarizes the wafer to a tolerance of about 0.3 μm over the area of a die about 10 mm by 10 mm in size.
A conventional belt polisher includes a belt carrying polishing pads, a wafer carrier head which holds a wafer, and a support assembly that supports the portion of the belt under the wafer. For CMP, the polishing pads are sprayed with a slurry, and pulleys drive the belt. The carrier head brings the wafer into contact with the polishing pads so that the polishing pads slide against the surface of the wafer. Chemical action of the slurry and the mechanical action of the polishing pads and particles in the slurry against the surface of the wafer remove material from the wafer's surface. U.S. Pat. Nos. 5,593,344 and 5,558,568 describe CMP systems using hydrostatic fluid bearings to support a belt. Such hydrostatic fluid bearings have fluid inlets and outlets for fluid flows forming films that support the belt and polishing pads.
In accordance with the invention, a polishing tool uses a sealed fluid chamber with a regulated pressure to support a compliant polishing material. The fluid chamber can be static or nearly static and maintained at a constant pressure without fluid flow. Thus, higher and lower pressure areas around fluid inlets and outlets are avoided. However, the pressure field of the chamber can be varied temporally or spatially if desired. For temporal variation, a control circuit operates a pressure regulator to vary pressure in the cavity. Temporal variations in the pressure can introduce vibrations in the polishing material which improve polishing performance. For spatial variations, fluid inlets and outlets are distributed according to where higher or lower pressures are desired. Each fluid inlet/outlet can be connected to an independent pressure regulator and/or fluid supply so that the supporting fluid pressure in the immediate vicinity of the inlet/outlet depends on the pressure to the inlet/outlet. Baffles or barriers can be placed among the inlet/outlets to increase the differential pressures.
In one embodiment of the invention, fluid in the chamber is in direct contact with a moving belt that carries the polishing pads, and a seal between the fixed portion of the cavity and the belt prevents or reduces leakage from the cavity. One type of seal includes an o-ring that the force of a spring, a magnet, or air pressure presses against the belt. A gas flow from outside the cavity or from an inlet inside the cavity forms a gas pocket in the cavity, adjacent the o-ring, to prevent the fluid from reaching and leaking past the o-ring. Another seal is formed by an air or gas bearing. The fluid pressure in the cavity can be varied temporally to create vibrations in the polishing material and enhance polishing performance or can be varied spatially to change the pressure profile. One embodiment of the invention includes one or more fluid inlet/outlets to the cavity, one or more pressure regulators, and a controller that operates the pressure regulators to control the pressure in the cavity.
In accordance with another aspect of the invention, a support structure for a polishing material in a polisher is mounted on actuators that control the orientation of the support structure. During polishing, an object such as a wafer being polished can tilt which causes a similar tilt in the polishing material. To reduce unevenness of polishing, the support structure changes orientation to match the tilt in the polishing material. Sensors and a control system can monitor the orientation of the polishing material and direct the actuators to position the support structure accordingly. This aspect of the invention can be employed with a support using a sealed fluid pocket for support of the polishing material or using other devices such as a hydrostatic bearing to support the polishing material. In one particular embodiment, an aerostatic bearing seals a fluid pocket, and a control system operates actuators to orient the support structure so that the aerostatic bearing functions properly. In this embodiment, the sensors can include pressure sensors that sense a drop in local pressure in the sealed fluid pocket caused by leakage past the aerostatic bearing. Distance sensors measuring the distance between the support structure and the polishing material can also be used.
FIG. 1 shows a portion of a polishing tool that, in accordance with an embodiment of the invention, includes a sealed fluid chamber that supports a polishing pad.
FIG. 2 shows a portion of a polishing tool that, in accordance with an embodiment of the invention, includes a sealed fluid chamber having a spatially modulated pressure.
FIGS. 3, 4, and 5 show embodiments of seals suitable for the fluid chamber of FIGS. 1 and 2.
FIGS. 6 and 7 show embodiments of support structures which adjust orientation to accommodate the orientation of a polishing material.
In accordance with an embodiment of the invention, a fluid chamber with a regulated pressure supports a compliant polishing material in a polishing tool. The pressure field of the fluid chamber can be constant or varied temporally or spatially. FIG. 1 shows a polisher in accordance with the invention in which a carrier head 110 holds a wafer 120 in position against a compliant polishing material 130. Co-filed U.S. patent application Ser. No. 08/956,033 UNKNOWN, entitled "Wafer Carrier Head with Inflatable Bladder and Attack Angle Control for Polishing", describes suitable carrier heads and is hereby incorporated by reference herein in it entirety. Compliant polishing material 130 may include for example, an endless belt made of stainless steel of thickness 0.005" to 0.060" on which polishing pads made of IC1000, Suba IV, IC1400 or other comparable polishing materials are mounted. IC1000, Suba IV, and IC1400 are available from Rodel, Inc. The width of the belt depends on the size of wafer 120. A fluid that is substantially static is contained in a cavity 140 bounded by a fixed structure 142, a seal 144, and a portion 134 of compliant polishing material 130. The pressure of the fluid (typically in the range between 0 and 60 psi) supports a portion of compliant polishing material 130 that is directly under and in contact with wafer 120. Portion 134 is larger than the area directly under wafer 120. The fluid in cavity 140 is preferably a liquid such as water and is introduced to cavity 140 via an inlet/outlet 146. Inlet/outlet 146 is connected through a pressure regulator 150 to a pressure supply 170.
A controller 160 connected to regulator 150 selects a desired pressure for cavity 140. Pressure supply 170 selectably operates as either a fluid source or a fluid sink depending on whether the fluid pressure in cavity 140 is less or greater than the inlet/outlet pressure. In accordance with an aspect of the invention, computer controller 160 modulates a control signal to regulator 150 to temporally vary the pressure to inlet/outlet 146 and in chamber 140. Modulation of the pressure in cavity 140 can vibrate compliant polishing material 130. For example, modulating the pressure at a frequency between 1 kHz and 10 kHz induces vibrations of a similar frequency in the polishing material. Ultrasonic frequency vibrations could also be used. Such vibrations are believed to improve polishing performance, provided that natural or resonant frequencies of the system are avoided.
FIG. 2 shows a portion of a polishing system using a cavity 240 containing a fluid with a spatially modulated pressure. Cavity 240 is in a structure 242 that includes multiple fluid inlets/outlets 246 and 248 which are connected to independent pressure supplies 270 and 272. Controller 160 uses separate pressure regulators 250 and 252 to control the pressures at inlet/outlets 246 and 248. With only two inlet/outlets as shown in FIG. 2, one of inlet/outlets 270 typically acts as a fluid inlet, and the other acts as a fluid outlet. In embodiments including more than two inlet/outlets, fluid flow among the inlet/outlets can be more varied, but the pressures near the inlets tend to be higher than the pressures near the outlets. Baffles 244 or barriers may be employed between inlet/outlet 246 and inlet/outlet 248 to restrict fluid flow and increase the pressure differential in the fluid. Controller 160 can maintain a constant pressure difference between inlet/outlets 244 and 248 or vary the pressure difference to create temporal pressure variations.
Spatial pressure variation in input pressure can address variations in the support pressure field of the sealed cavity. For example, if fluid leaks from cavity 240, pressure to inlets 246 and 248 can be adjusted to compensate for support pressure differences caused by the leakage. Additionally, spatial variation in fluid pressure can compensate for non-fluid support related effects. For instance, if a wafer rotates during polishing, the velocities of portions of the wafer relative to the pad change with radius. A fluid pocket with spatially varied pressure profile can compensate for the different removal rates caused by differences in wafer velocity relative to the belt. For example, the support pressure can provide a higher pressure under an area where relative velocity between the polishing material and the wafer is lower. The pressure profile can also be varied to compensate for unevenness in conditioning of the belt with slurry. Specifically, more pressure can be applied where polishing rates would otherwise be lower. Additionally, polishing action tends to wear the pad into the shape of a trough causing slower material removal from the portion of the wafer over central regions of the pad. The pad may further have a low spot at any position on the belt. Spatial and/or temporal variation in the pressure can be used to press harder on the belt at the low spots so that removal rates are more uniform and polishing performance is improved. Such pressure variations can be tied to a feedback loop including a sensor that measures the properties of the belt. Co-filed U.S. patent Application Ser. No. 08,946,772, entitled "In-Situ Monitoring of Polishing Pad Wear", describes polishers that include sensors for measuring polishing pads and control systems for changing the polisher's operating parameters (such as the pressure profile of a belt support) and is incorporated by reference herein in its entirety.
During polishing, polishing material 130 moves relative to fixed structure 142 and seal 144. Seal 144 is at the interface between fixed structure 142 and compliant polishing material 130 and prevents or reduces fluid leakage from chamber 140. FIG. 3 shows an embodiment of a seal 300 that is suitable for sealing cavity 140. Seal 300 includes an o-ring 320 that a mechanism including a spring 330 presses against the underside of polishing material 130. A variety of alternative structures can be used in place of o-ring 320. For example, a face sealing lip could be applied to the polishing material 130. To reduce friction and wear, o-ring 320 can be replace by a magnetic fluid magnetically confined to the gap between polishing material 130 and fixed structure 142.
Alternative mechanisms for applying o-ring 320 to polishing material 130 include a pressurized or hydraulic cylinder or a magnet. A magnet in a structure 310 on an opposite side of belt 130 from o-ring 320 can attract iron or a magnetic material under o-ring 320 to press o-ring 320 against polishing material 130. Alternatively, a magnet under o-ring 320 can either be attracted to iron or any magnetic material in structure 310 or in the polishing material 130. For example, a belt in a belt polisher can include iron (e.g., a stainless steel belt) or any magnetic material so that mutual attraction between the magnet under o-ring 320 and the belt presses o-ring 320 into polishing material 130. When magnetic attraction to the belt is used, structure 310 on the side of polishing material 130 opposite o-ring 320 is not required. Otherwise, structure 310 applies an opposing force to keep polishing material 130 from moving away from o-ring 320. Structure 310 may be, for example, a portion of carrier head 110 or an independent structure having a fixed location relative to cavity 140.
To improve the seal provided by o-ring 320, an air (or other gas) flow 340 is directed at o-ring 320 from outside cavity 140. The air flow is at a pressure greater than the pressure of fluid 140 so that any leakage past o-ring 320 into cavity 140 and forms a gas pocket 350 adjacent o-ring 320. Gas pocket 350 prevents fluid from leaking out of cavity 140. FIG. 4 shows a seal 400 that contains many of the same elements as seal 300 of FIG. 3. Seal 400 differs from seal 300 by including a gas inlet 440 inside cavity 140 and adjacent o-ring 320. An inflow through inlet 440 forms a gas pocket 450 which keeps fluid in cavity 140 and away from seal 320. Accordingly, any leakage past o-ring 320 is predominately gas from pocket 450, and the fluid that supports polishing material 130 under wafer 120 is kept in cavity 140. If desired, a gas outlet from gas pocket 350 or 450 can be provided in cavity 140 to improve regulation of the pressure in the gas pocket.
FIG. 5 shows a seal 500 which uses an aerostatic bearing to prevent leakage from cavity 140. The aerostatic bearing has the advantage of providing a nearly frictionless contact that will not generate particles that can interfere with polishing. The aerostatic bearing includes gas inlets 540 and 544 and a gas outlet 542 that are arranged around the perimeter of cavity with inlet 540 being closest to the fluid that supports the polishing material beneath wafer 120. Gas from inlets 540 and 544 flow out through outlet 542 forming a cushion between fixed surfaces 530 and polishing material 130. The gas pressure to fluid inlets 540 is higher than the fluid pressure in cavity 140 so that a gas pocket 550 forms and stops or reduces fluid leakage from cavity 140. In an exemplary embodiment, the pressure at inlets 540 and 544 is about 5 to 100 psi, the pressure at outlet 542 is about 0 to -10 psi, and the gap between surfaces 530 and polishing material 130 is between about 5 and 20 μm.
FIG. 6 shows a polisher 600 having a support structure 650 that includes an aerostatic 655 bearing to seal a fluid pocket 140. The aerostatic bearing 655 has several parameters such as orifice size, gas flow rate, gas pad size, and landing size that are selected according to the requirements of polisher 600. In particular, the size of wafer 120 to be polished determines the required diameter of fluid pocket 140 and the diameter of the aerostatic bearing that surrounds fluid pocket 140. The aerostatic bearing 655 should approximately match the diameter of carrier head 110 which holds wafer 120. The aerostatic bearing 655 also requires a stiffness and load capacity selected according to pressures applied during polishing.
The thickness of the gas film flowing between structure 650 and belt 130 is critical to operation of an aerostatic bearing/seal. Film thicknesses 61 and 82 are for gaps on opposite sides of the aerostatic bearing 655 and ideally should be equal. During polishing, motion of belt 130 causes friction and a shear force on wafer 120 that may cause wafer 120 to tilt. This can cause belt 130 to tilt and change film thicknesses δ1 and δ2. In a worst case, the aerostatic bearing 655 fails and allows the moving belt 130 to contact support structure 650. In accordance with an aspect of the invention, support structure 650 has a mounting that permits tilting of structure 650 to match the angle of belt 130 and a control system that monitors the relative orientation of support structure 650 and belt 130 and adjusts the orientation of support structure 650 as required to maintain a uniform gap for the aerostatic bearing 655. Such control systems can be implemented using special purpose hardware and/or a general purpose computer system executing appropriate software.
In FIG. 6, support structure 650 is mounted on air springs 620 and 625 that are respectively connected to independent pressure sources 630 and 635. Pressure sensors 610 and 615, which measure local pressure in fluid pocket 140, are the same distance from the aerostatic bearing 655 and near associated air springs 620 and 625 respectively. If during polishing belt 130 tilts and changes gaps δ1 and δ2, fluid leakage from pocket 140 increases at the wider gap δ1 or δ2, causing fluid pressure to drop near the wider gap. A control unit 640, which is connected to pressure sensors 610 and 615 and to the pressure sources 630 and 635 for air springs 620 and 625, detects difference between pressures measured by sensors 620 and 615 and responds by increasing the pressure to the air spring 625 or 620 near the wider gap and/or decreasing the pressure to the air spring 620 or 625 near the narrower gap. The change in pressure to the air springs 620 and 625 causes support structure 650 to tilt until sensors 610 and 615 measure the same pressure, indicating gaps δ1 or δ2 are the same.
More generally to control the air gap and orientation for an aerostatic bearing requires three or more actuators. FIG. 7 shows an expanded perspective view of a support using six air bearings 720. Mounted on air springs 720 are plates 740 and 750 which include a cavity 745 for a fluid pocket. In cavity 745 are eight pressure sensors 710. A control circuit uses measurements from pressure sensors 710 to determine the pressure distribution in the cavity and from the determined pressure distribution pressurizes air springs 720 as required for proper operation of an aerostatic bearing formed between plate 740 and a polishing material being supported.
The embodiments of FIGS. 6 and 7 can be altered in a variety of ways in keeping with the invention. For example, any actuators, such as piezoelectric transducers, hydraulic cylinders, or solenoids can be employed instead of the air springs to control the orientation of the support structure. Additionally, distance sensors, which directly measure the gaps between the support structure and the overlying belt can be used instead of or in combination with pressure sensors in a cavity. A control system uses multiple distance measurements to position the support structure. Further, although the adjustable mounting and feedback control systems have been described for use with supports including sealed fluid pockets having surrounding aerostatic bearings, other embodiments of the invention can include a support with an adjustable orientation and a control system to match the orientation of a polishing material but without a sealed fluid pocket or aerostatic bearing. For example, such embodiments can employ a hydrostatic bearing to support a polishing material with or without a surrounding aerostatic seal. U.S. patent Application. Ser. No. 08/964,773, entitled "Polishing System Including a Hydrostatic Fluid Bearing Support", which is hereby incorporated by reference herein in its entirety, describes hydrostatic bearings suitable for use with in a support having an adjustable orientation. A solid support bearing could also be employed. In such embodiments, the support adjusts its orientation to accommodate tilt of an object being polished. Accordingly, the support provides a more even polishing pressure.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS3447306 *Sep 16, 1966Jun 3, 1969Barnes Drill CoAbrading machineUS4628640 *Jan 17, 1985Dec 16, 1986Johannsen Hans PeterBelt sander apparatusUS5081795 *Jan 22, 1991Jan 21, 1992Shin-Etsu Handotai Company, Ltd.Polishing apparatusUS5297361 *Jul 16, 1993Mar 29, 1994Commissariat A L'energie AtomiquePolishing machine with an improved sample holding tableUS5558568 *Nov 2, 1994Sep 24, 1996Ontrak Systems, Inc.Wafer polishing machine with fluid bearingsUS5593344 *Oct 11, 1994Jan 14, 1997Ontrak Systems, Inc.Wafer polishing machine with fluid bearings and drive systemsUS5692947 *Dec 3, 1996Dec 2, 1997Ontrak Systems, Inc.Linear polisher and method for semiconductor wafer planarization* Cited by examinerReferenced byCiting PatentFiling datePublication dateApplicantTitleUS6186865 *Oct 29, 1998Feb 13, 2001Lam Research CorporationApparatus and method for performing end point detection on a linear planarization toolUS6196899 *Jun 21, 1999Mar 6, 2001Micron Technology, Inc.Polishing apparatusUS6325706Oct 29, 1998Dec 4, 2001Lam Research CorporationUse of zeta potential during chemical mechanical polishing for end point detectionUS6358118 *Jun 30, 2000Mar 19, 2002Lam Research CorporationField controlled polishing apparatus and methodUS6361411Jan 31, 2000Mar 26, 2002Micron Technology, Inc.Method for conditioning polishing surfaceUS6439967Sep 1, 1998Aug 27, 2002Micron Technology, Inc.Microelectronic substrate assembly planarizing machines and methods of mechanical and chemical-mechanical planarization of microelectronic substrate assembliesUS6607425Dec 21, 2000Aug 19, 2003Lam Research CorporationPressurized membrane platen design for improving performance in CMP applicationsUS6612904Dec 27, 2001Sep 2, 2003Lam Research CorporationField controlled polishing apparatusUS6672949Feb 28, 2001Jan 6, 2004Micron Technology, Inc.Polishing apparatusUS6729945 *Mar 30, 2001May 4, 2004Lam Research CorporationApparatus for controlling leading edge and trailing edge polishingUS6736708 *Oct 13, 2000May 18, 2004Micron Technology, Inc.Microelectronic substrate assembly planarizing machines and methods of mechanical and chemical-mechanical planarization of microelectronic substrate assembliesUS6761626 *Dec 20, 2001Jul 13, 2004Lam Research CorporationAir platen for leading edge and trailing edge controlUS6776695Dec 21, 2000Aug 17, 2004Lam Research CorporationPlaten design for improving edge performance in CMP applicationsUS6913521Jun 22, 2004Jul 5, 2005Lam Research CorporationMethods using active retainer rings for improving edge performance in CMP applicationsUS6939212Dec 21, 2001Sep 6, 2005Lam Research CorporationPorous material air bearing platen for chemical mechanical planarizationUS6955588Mar 31, 2004Oct 18, 2005Lam Research CorporationMethod of and platen for controlling removal rate characteristics in chemical mechanical planarizationUS6969309Mar 29, 2004Nov 29, 2005Micron Technology, Inc.Microelectronic substrate assembly planarizing machines and methods of mechanical and chemical-mechanical planarization of microelectronic substrate assembliesUS6988934 *Sep 29, 2003Jan 24, 2006Lam Research CorporationMethod and apparatus of a variable height and controlled fluid flow platen in a chemical mechanical polishing systemUS7018273Jun 27, 2003Mar 28, 2006Lam Research CorporationPlaten with diaphragm and method for optimizing wafer polishingUS7018276Jun 25, 2004Mar 28, 2006Lam Research CorporationAir platen for leading edge and trailing edge controlUS7077733 *Aug 31, 2000Jul 18, 2006Micron Technology, Inc.Subpad support with a releasable subpad securing element and polishing apparatus including the subpad supportUS7153182Sep 30, 2004Dec 26, 2006Lam Research CorporationSystem and method for in situ characterization and maintenance of polishing pad smoothness in chemical mechanical polishingUS7273411Nov 24, 2003Sep 25, 2007Micron Technology, Inc.Polishing apparatusUS7278905Apr 25, 2006Oct 9, 2007Micron Technology, Inc.Apparatus and method for conditioning polishing surface, and polishing apparatus and method of operationUS7361078Apr 6, 2006Apr 22, 2008Micron Technology, Inc.Subpad support with releasable subpad securing element and polishing apparatusUS7367873 *Feb 12, 2003May 6, 2008Ebara CorporationSubstrate processing apparatusUS7377018Dec 4, 2002May 27, 2008Micron Technology, Inc.Method of replacing a subpad of a polishing apparatusUS7431634 *Feb 6, 2007Oct 7, 2008Samsung Electronics, Co., Ltd.Platen assembly, apparatus having the platen assembly and method of polishing a wafer using the platen assemblyUS7591061Dec 4, 2002Sep 22, 2009Micron Technology, Inc.Method for securing a subpad to a subpad supportUS7831327 *Nov 30, 2007Nov 9, 2010Corning IncorporatedPrecision abrasive machining of work piece surfacesUS8822307 *Mar 16, 2012Sep 2, 2014Kabushiki Kaisha ToshibaSemiconductor manufacturing apparatus and semiconductor manufacturing methodUS20120171933 *Dec 13, 2011Jul 5, 2012Applied Materials, Inc.Pressure controlled polishing platenUS20120329241 *Mar 16, 2012Dec 27, 2012Kabushiki Kaisha ToshibaSemiconductor manufacturing apparatus and semiconductor manufacturing methodUS20130217228 *Aug 30, 2012Aug 22, 2013Masako KoderaMethod for fabricating semiconductor deviceCN100431789CDec 12, 2002Nov 12, 2008拉姆研究公司Air platen for leading edge and trailing edge controlWO2003053633A1 *Dec 12, 2002Jul 3, 2003Lam Res CorpAir platen for leading edge and trailing edge control* Cited by examinerClassifications U.S. Classification451/303, 451/5, 257/E21.23, 451/173International ClassificationH01L21/306, B24B37/00, B24B21/04, B24B49/16, B24B57/02, B24B37/04Cooperative ClassificationB24B21/04, B24B57/02, B24B49/16, B24B37/16European ClassificationB24B37/16, B24B21/04, B24B49/16, B24B57/02Legal EventsDateCodeEventDescriptionDec 27, 2011FPExpired due to failure to pay maintenance feeEffective date: 20111109Nov 9, 2011LAPSLapse for failure to pay maintenance feesJun 13, 2011REMIMaintenance fee reminder mailedMay 9, 2007FPAYFee paymentYear of fee payment: 8May 24, 2004ASAssignmentOwner name: PROMOS TECHNOLOGIES INC., TAIWANFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:MOSEL VITELIC, INC.;REEL/FRAME:015334/0772Effective date: 20040427Owner name: PROMOS TECHNOLOGIES INC. 3F, NO.19, LI-HSIN ROAD SFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:MOSEL VITELIC, INC. /AR;REEL/FRAME:015334/0772May 28, 2003REMIMaintenance fee reminder mailedMay 8, 2003FPAYFee paymentYear of fee payment: 4Oct 23, 2000ASAssignmentOwner name: MOSEL VITELIC, INC., TAIWANFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:APLEX, INC.;REEL/FRAME:011204/0152Effective date: 20000905Owner name: MOSEL VITELIC, INC. SCIENCE BASED INDUSTRIAL PARKNov 5, 1997ASAssignmentOwner name: APLEX GROUP, CALIFORNIAFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:CHANG, SHOU-SUNG;KAO, SHU-HSIN;WELDON, DAVID E.;REEL/FRAME:008807/0905Effective date: 19971104RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services


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P. 1Bahagian Tumbuhan Yang Penting TrpBahagian Tumbuhan Yang Penting TrpRatings: (0)|Views: 2
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Valley Alternator Sales & Service - Creighton, PA | Groupon
Valley Alternator Sales & Service
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value: This website is an American global e-commerce marketplace connecting subscribers with local merchants by offering activities, travel, goods and services in 15 countries. Based in Chicago, Groupon was launched there in November 2008, launching soon after in Boston, New York City and Toronto.


text:
Backlinks dating site Jobs, Employment | Freelancer.com
backlinks dating site jobs found, pricing in USD
...100 one way links to my site from >PR4 websites, the links will point to several pages of my site and i will provide you the anchor text i want for each link. Links must be of high quality relevant coming from aged sites.
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Backlink GURU !!!!! PR7 And PR8 Contextual Anchor text Backlink Required
- Backlinks must be search
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The articles MUST be written in the voice of a man and follow my own style of writing (I'll
It has PR 1 , it's already ranked #10 position on Bing for the keyword " site de rencontre gratuit " , not ranked with google yet. I want to be ranked FIRST POSITION on both [url removed, login to view] and [url removed, login to view] for this keyword.
I will release full pay...
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- Links must be strictly from Google PR3+ pages - , iframe pages and with PR less than 3 or mirrowed PR do not count
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...subpages with static Link PR3+ Allowed.
- Web Site tech Audit and if any issues found to be addressed.
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Custom Project Mar 15 2013 13:17:46
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Need blog commenting for our Dating site, the comments with our anchor text backlinks must be coming from related PR2+ page. Please read All criteria and start your PM with word . BLOG
All Links must be Manually submitted. No automated techniques or black / grey hat techniques . URL must not contain “.../links/”
Links must be permanent, relevant, dofollow, page ranks must be 3-6 average page rank must be 4 or above, one way, non-reciprocal and static (in-content preferred), no more than
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value: This website is an Australian freelance marketplace website, which allows potential employers to post jobs that freelancers can then bid to complete. Founded in 2009, its headquarters is located in Sydney, Australia, though it also has offices in Vancouver, London, Buenos Aires, Manila, and Jakarta.


text:
U.S. Traveler Travel Bags : Luggage - Walmart.com Hello, {0}. Sign Out|Help New customer? Sign In|Help Summer savings start now with Memorial Day Online Specials Value of the Day Local Ad - For Change
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text:
Gymboree Fall for Autumn Nuts About Daddy Long Sleeve Green Tee 18 24 2T | eBay
NWT Gymboree FALL FOR AUTUMN Green... $10.88
Gymboree Fall for Autumn Green... $11.40
NWT Gymboree Long Sleeve Girls Top Tee... $11.49
Gymboree NWT Fall for Autumn Squirrel Lo... $12.14
NWT GYMBOREE Fall for Autumn Nuts... $12.50
NWT Gymboree Smart Kitty Pink Corduroy... $9.99
Gymboree Holiday Friends Lot Jumper... $19.99
NWT Gymboree Panda Academy Heart Print... $11.99
NWT Baby Gap Purple Embroidered Eyelet... $19.99
EUC Baby Gap Gray Grey Hooded... $1.99
NWT Gymboree Fall for Autumn Nuts About Daddy Long Sleeve Green Tee 18 24 2T
lizmorgan710
2T	18-24 Months[out of stock]
eBay item number:120837564086
Mar 10, 2012 13:05:20 PST View all revisions
NWT Gymboree Fall for Autumn
Nuts About Daddy Long Sleeve Green Tee
Size 18-24 Months or 2T
This adorable green long sleeve tee is embroidered and appliqued with a squirl and "Nuts About Daddy" across the chest. The shoulders have gathered fabric for added style. Perfect for fall or spring! Choose from size 18-24 months or 2T
Check out my other listings - I love to combine shipping! Thanks for looking! I do my best to represent my items as accurately as possible. Please contact me if you have any questions that this listing does not cover. I am happy to take additional photos and send them to you. Your satisfaction is important to me.
Payment is expected via PayPal within 3 days. I will open a case to recover my eBay fees if payment is not received. Please do not bid if you do not intend to pay. If you are bidding on multiple items, please let me know and I am happy to combine shipping and will gladly wait a few more days to receive payment. All items include delivery confirmation, insurance is an additional cost to the buyer.
I do my best to keep your shipping costs down. As someone who purchases items on eBay, I appreciate low shipping costs. I do charge a small amount (about $.50 to $1) to cover the costs I incur ($.30 charged by PayPal, $.25 for shipping materials, 2.9% charged by PayPal). I am HAPPY to combine shipping and will work to get you the best deal possible as long as the items are paid for ON THE SAME INVOICE. Please condact me if you are bidding on multiple items. I am happy to provide you with a shipping quote, based on the weight and packaging of the items. Also, keep in mind that the USPS offers flat rate boxes and I will fit as much as possible into one of those and charge you only the cost of the box (10.20 or 13.95) plus $.50 more for handeling. This means that on US addresses, combined shipping is rarely over 14.45 even when lots of auctions are won. Shipping costs include delivery confirmation and are almost always USPS First Class, Priority, or Media rates. Shipping costs are to US addresses only. INTERNATIONAL BUYERS: PLEASE READ BELOW! Due to eBay's Seller Protection Policy, I will no longer offer International First Class Shipping. I will ship Internationally using PRIORITY or EXPRESS shipping ONLY. I recognize this is significantly more expensive, especially for Canadian buyers, but unfortunately eBay will not protect me unless the package has a tracking number and International First Class shipping does not allow for tracking. International buyers, please contact me for a shipping quote and wait for an invoice prior to paying for your item. International buyers are responsible for any additional fees associated with customs or tarrifs. Please note that you will be charged $1.00 handling per item in addition to the actual postage cost. This covers the 3.9% of the total purchase price that I am charged by PayPal for International transactions. Please do not hold this against me in Feedback as it allows me to keep costs down for everyone. I assure you I am not making any money off of International shipping. Free Shipping applies only to US addresses, International buyers will receive a shipping discount equal to the actual cost of US shipping.
I will give you feedback once payment is received. Please leave me feedback when your item is received. I will also do you the courtesy of contacting you with any concerns I have about the transaction prior to leaving feedback. Please do me the same courtesy. All items come from a clean, smoke free home. We do have a dog who is not allowed near the items I am selling. New items are immediately placed in ziplock storage bags to prevent stray hairs or dander from reaching the clothes. All clothes (new and used) are stored in plastic bins. All used clothes have been washed in dye and fragrence free detergent.Add to Favorite SellersOther Items To view the showcase you need Flash 6 or higher. Click here to Install it now.--or-- View Other Listings for lizmorgan710
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Gymboree Fall for Autumn,

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text:
Hello, me old China! | Daily Mail Online
Hello, me old China!
By Adam Hart-Davis, Daily Mail
Last updated at 18:25 10 April 2007
The Great Wall: You should see the size of the garden
No matter where you go in the world, you can always spot the middle-class British couple. We are the ones desperately trying not to offend the locals. Hula skirts, plates of innards, strange smoking receptacles, weird folk dances - we gamely endure them all in the name of international relations and good manners.
In China, it's snake wine. 'You will love it,' our host had insisted as my partner Susan and I stared at the amber-coloured liquid encased in a bottle half-crammed with, well, a whole dead snake.
As aperitifs go, it wouldn't have been our first choice but we gave it a shot, just to be polite, of course. (For the record, should you find yourself in a similar situation, it tastes much like sherry, quite pleasant really, and it helps if you keep your eyes off the scaly hostage).
Something about the experience put me in mind of the Victorians' fascination with bizarre, vaguely sinister, fairground attractions.
The sort that were still around during my childhood summer breaks, which I spent with an elderly aunt at her summer house in Bognor. To a naive young public schoolboy, the place was glorious and the occupants of the endof-pier stalls mesmerising.
Maybe it is because I was a war baby, born into an era when people just felt lucky to be alive, but I have never lost that wide-eyed appetite for the new, and so I finally decided that the time had come for a tour of China's exotic highlights.
Susan and I had never been to China, and while we have all seen endless images of the Great Wall (well, you can see it from space) and the Terracotta Warriors, seeing them for real is truly something else.
What's more, the Chinese people seem genuinely keen to meet visitors from the West. In fact, China is a much less complicated place to visit than Japan, largely because they don't suffer from the same crippling layers of formality and politeness.
That's not to say that I wouldn't go back to Japan like a shot - it was wonderful when I last visited - it's just that things are much simpler in China.
Apart from the architecture, that is. The Forbidden City in Beijing, for example, covers a staggering 150 acres. It is enclosed by magnificent walls, which encompass 800 separate buildings and countless gardens and courtyards that were once used for regal ceremonies.
Every corner of every roof is decorated with a row of animals and the number of animals denotes the importance of the building.
Most buildings have five animals, but the emperor's house has seven, while the big ceremonial hall is a... drum roll, please... nine-animal building.
And there's plenty of mysticism, too. Throughout the complex, you will find foot-high barriers, designed, apparently, to exclude ghosts. Chinese ghosts are decreed to have no knees and, because they were kneeless, it was assumed they would not be able to step over these barriers. It's true, you try stepping over a barrier with straight legs.
Western ghosts, of course, would have no trouble with these obstacles, trailing off as they do into a wispy tail. But the ancient builders weren't expecting many foreign visitors at the time.
It is a mark of some progress, I suppose, that when the last emperor, Pu Yi, was given a bicycle, he decided to take his chances with the ghosts and had some of the gateways removed so he could cycle around the grounds freely.
The more I see of the world, the more fascinated I become with the way different cultures deal with the afterlife and the extraterrestrial.
I once made a TV programme with the science fiction author Arthur C. Clarke and was amazed to discover that he was often invited to stay at the Vatican.
Curiously, the Vatican has an official astronomer and the last Pope was very keen on Arthur C. Clarke and his writing. Arthur C. appeared a little less enthusiastic. I remember once going to see him and watching him open his post, and him saying: 'Oh dear, another letter from the Pope' - as if it were just another correspondence.
One of the great things about travelling is the chance to eat things you wouldn't get at home. Like most people, my view of Chinese food was informed by the local take-away and the hybrid pan-Asian cuisine that we all consume so much of these days.
There is certainly plenty of that in the big hotels, but it is possible to step outside the tourist bubble and eat like a native, too.
In one smart area of Beijing, we found a street full of restaurants and randomly chose one on a corner.
With plastic tables and a fast turnover, it wasn't exactly chic, but the place was fun and the food excellent. I had a large local beer, a bowl of noodles with black mushrooms - which were utterly delicious - and a bowl of wonton dumplings, which I couldn't possibly finish without bursting.
The total cost came to 17 Yuan - about £1.30. In anyone's book, that was hardly taxing.
Within walking distance of the Forbidden City is Tiananmen Square. If you think of Trafalgar Square multiplied by ten, and then place a huge portrait of Chairman Mao (repainted every year to make him look younger and younger) at one end, you'll have a pretty good picture of it.
Sadly, it really has no redeeming architectural features. Apparently, the early communists saw Red Square in Moscow and thought 'oh, we'll have one of those - but bigger'. Unfortunately, they failed to add anything quite as spectacular as St Basil's Cathedral. Still, it is what it is, and the portrait is certainly worth seeing, if only for its scale.
Besides, if you're here for architecture, the Great Wall's only just out of town. You can join it at Jinshanling, about three hours away.
It may have been breached by enemies, by roads, and by the railway, but it remains a truly magnificent barrier.
Rather similar to the relatively Lilliputian Hadrian's Wall, but higher and wider and much, much longer, it stretches nearly 4,000 miles, compared to Hadrian's measly 75 (although the Chinese say they don't know the exact length).
The first serious wall was built around 200 BC and, like our own effort, was made of earth and stone to keep out neighbouring barbarians. Then, between the 15th and 17th centuries, the whole thing was reconstructed in brick and stone for greater strength.
It is around 13ft to 16ft high and the same width across. We were told that it was built to be wide enough for four horsemen to ride along abreast, but this seemed a little unfeasible from what I could see. Two or possibly three, but not four - unless the horses were severely emaciated.
Building the wall must have been an extraordinary feat. Finding and transporting the stone and other materials alone must have been immensely difficult.
Much of the wall goes over the peaks of remote mountains, where the weather is severe, and there is no shelter or food. And I thought the Eton Wall Game was tough.
The early wall was built on the orders of Qin Shi Huang, who unified China and then ruled it as emperor between 221 and 210 BC.
And if that wasn't glory enough, he was also responsible for the construction of the famous Terracotta Army (made up of 8,000 lifesize individuals) that stands guard over his mausoleum.
They can be found in the middle of open country, a few miles outside the walled city of Xian (pronounced Shian). Three huge sheds now cover the pits in which they were originally discovered in the Seventies.
The soldiers are all individuals, with their own expressions and subtly different clothes, but they all stand to attention as if waiting for the next order.
From the positioning of their hands, it is clear that some of them once held swords or spears.
Sadly, the tomb was raided centuries ago during a rebellion, and the thieves stole their weapons and set fire to the army's protective barracks, bringing the roof down and shattering many of the warriors. Fortunately, terracotta doesn't burn and modern archaeologists were able to put them back together again.
As this was a whirlwind tour of China, we also managed to fit in three days on a boat on the magnificent Yangtze River. We floated down through the Three Gorges, of which the first in particular is stunning - great cliffs soaring 330ft out of the water, and the river churning between the walls.
At one point, we saw a coffin resting in a narrow cave high up the cliff-face, but no one could tell us how it got there. It was just another of China's mysteries.
Everywhere we went, we saw tremendous expansion - new roads, new railways, new bridges. Beijing, in particular, is gearing up at breakneck speed for the 2008 Olympics.
According to the haunting Katie Melua song of the same name, 'there are nine million bicycles in Beijing'. In fact, bicycle inflation is galloping. There are now 11 million bicycles here, and a staggering 16 million people.
In Shanghai, by contrast, the scooter is taking over from the push-bike. At every set of traffic lights, there is a moped scrummage. The city centre is a labyrinth of crowded streets and wonderful buildings, both ancient and dramatically modern - especially on the Bund, Shanghai's magnificent riverside strip.
Our final stop was Guilin, in China's deep south. Guilin is warm, even in winter, and if you've ever admired the mythical landscapes that decorate many Chinese restaurants, this is where they are painted.
A flat alluvial plain of ancient paddy fields, is liberally spattered with thousands of extraordinary hills, which rise like rockets out of the ground and go up almost vertically to several hundred feet. This amazing landscape seems to go on forever and is pure, Chinese magic.
In Guilin we feasted, if that is the right word, on deep-fried miniature crabs (whole, with their legs and pincers left on) and snake wine - yes, more snake wine.
Almost inevitably, we brought back a couple of bottles as presents. We gave one to our wonderful 75-year-old cleaner and her 80-year-old boyfriend, Jim.
'Ooh,' she said. 'That's a bit different.' Which pretty much sums up China.
Cox and Kings (020 7873 5000; www.coxandkings.co.uk) offer a nine-night tour around China that takes in Beijing, Xian, Nanjing and Shanghai. Prices start from £1,515 per person including British Airways flights, half-board accommodation, transfers and guided excursions.

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text:
Top 10 Hotels in State College, PA $90 | Cheap Hotels on Expedia
Hotels in State College, PAFlight onlyHotel only Over 321,000 worldwideFlight + HotelState College HotelsPlease correct the errors belowCheck-inCheck-outRooms123456789+Adults (18+)1234567891011121314Children (0-17)0123456Child 1: Age <11234567891011121314151617Child 2: Age <11234567891011121314151617Child 3: Age <11234567891011121314151617Child 4: Age <11234567891011121314151617Child 5: Age <11234567891011121314151617Child 6: Age <11234567891011121314151617Room 1Adults (18+)1234567891011121314Children (0-17)0123456Child 1: Age <11234567891011121314151617Child 2: Age <11234567891011121314151617Child 3: Age <11234567891011121314151617Child 4: Age <11234567891011121314151617Child 5: Age <11234567891011121314151617Child 6: Age <11234567891011121314151617Room 2Adults (18+)1234567891011121314Children (0-17)0123456Child 1: Age <11234567891011121314151617Child 2: Age <11234567891011121314151617Child 3: Age <11234567891011121314151617Child 4: Age <11234567891011121314151617Child 5: Age <11234567891011121314151617Child 6: Age <11234567891011121314151617Room 3Adults (18+)1234567891011121314Children (0-17)0123456Child 1: Age <11234567891011121314151617Child 2: Age <11234567891011121314151617Child 3: Age <11234567891011121314151617Child 4: Age <11234567891011121314151617Child 5: Age <11234567891011121314151617Child 6: Age <11234567891011121314151617Room 4Adults (18+)1234567891011121314Children (0-17)0123456Child 1: Age <11234567891011121314151617Child 2: Age <11234567891011121314151617Child 3: Age <11234567891011121314151617Child 4: Age <11234567891011121314151617Child 5: Age <11234567891011121314151617Child 6: Age <11234567891011121314151617Room 5Adults (18+)1234567891011121314Children (0-17)0123456Child 1: Age <11234567891011121314151617Child 2: Age <11234567891011121314151617Child 3: Age <11234567891011121314151617Child 4: Age <11234567891011121314151617Child 5: Age <11234567891011121314151617Child 6: Age <11234567891011121314151617Room 6Adults (18+)1234567891011121314Children (0-17)0123456Child 1: Age <11234567891011121314151617Child 2: Age <11234567891011121314151617Child 3: Age <11234567891011121314151617Child 4: Age <11234567891011121314151617Child 5: Age <11234567891011121314151617Child 6: Age <11234567891011121314151617Room 7Adults (18+)1234567891011121314Children (0-17)0123456Child 1: Age <11234567891011121314151617Child 2: Age <11234567891011121314151617Child 3: Age <11234567891011121314151617Child 4: Age <11234567891011121314151617Child 5: Age <11234567891011121314151617Child 6: Age <11234567891011121314151617Room 8Adults (18+)1234567891011121314Children (0-17)0123456Child 1: Age <11234567891011121314151617Child 2: Age <11234567891011121314151617Child 3: Age <11234567891011121314151617Child 4: Age <11234567891011121314151617Child 5: Age <11234567891011121314151617Child 6: Age <11234567891011121314151617Adults (18+)9101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899Children (0-17)0123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899Search Search 321,000 hotels worldwide.
See all 34 Hotels in State College The Atherton Hotel, an Ascend Hotel Collection Member The Atherton Hotel, an Ascend Hotel Collection Member 125 S Atherton St, State College 16801 3.0 out of 5.03.9 out of 5 (436 reviews) Located in the heart of State College, this hotel is within a 10-minute walk of Discovery Space of Central Pennsylvania and … $79Days Inn Penn State Days Inn Penn State 240 South Pugh Street, State College 16801 3.0 out of 5.04.2 out of 5 (1,055 reviews) Located in downtown State College, this Days Inn is 1 block from Penn State's University Park campus. Beaver Stadium, home of … $108Hampton Inn State College Hampton Inn State College 1101 E College Ave, State College 16801 2.5 out of 5.04.3 out of 5 (499 reviews) Located in the heart of State College, this hotel is within 1 mi (2 km) of Centre County Historical Society, What-A-Blast … $88Country Inn & Suites State College Country Inn & Suites State College 1357 E College Ave, State College 16801 3.0 out of 5.04.6 out of 5 (750 reviews) Situated in State College, this hotel is within 2 mi (3 km) of Centre County Historical Society, Beaver Stadium, and … $90The Nittany Lion Inn The Nittany Lion Inn 200 West Park Avenue, State College 16803 3.5 out of 5.04.6 out of 5 (466 reviews) Situated in a rural location, this historic hotel is within a 15-minute walk of Palmer Museum of Art and Pennsylvania State … $139Rodeway Inn State College Rodeway Inn State College 1040 N Atherton St, State College 16803 2.0 out of 5.03.8 out of 5 (377 reviews) Situated in State College, this hotel is within 1 mi (2 km) of Palmer Museum of Art, The Arboretum at Penn State, and … $66The Penn Stater Hotel and Conference Center The Penn Stater Hotel and Conference Center 215 Innovation Boulevard, State College 16803 3.5 out of 5.04.4 out of 5 (603 reviews) This family-friendly State College hotel is located near the airport, within 3 mi (5 km) of Beaver Stadium, Bryce Jordan … $119Holiday Inn Express State College at Williamsburg Square Holiday Inn Express State College at Williamsburg Square 1925 Waddle Rd, State College 16803 2.5 out of 5.04.3 out of 5 (277 reviews) Situated in State College, this hotel is within 3 mi (5 km) of The Arboretum at Penn State, Palmer Museum of Art, and Penn … $100Hilton Garden Inn State College Hilton Garden Inn State College 1221 E College Ave, State College 16801 3.0 out of 5.04.5 out of 5 (252 reviews) Located in the heart of State College, this hotel is within 2 mi (3 km) of Centre County Historical Society, Beaver Stadium … $110Quality Inn & Suites Quality Inn & Suites 13015 Ferguson Valley Rd, Burnham 17009 2.5 out of 5.03.2 out of 5 (144 reviews) Situated in a rural location, this hotel is within 20 mi (32 km) of Seven Mountains Wine Cellars, Juniata County Courthouse … $64
Nice hotel, plenty of parking, near restaurants4 out of 5 Hotel staff was very friendly and helpful. Hotel was nice, room was large with comfortable bed. A verified traveler stayed at Holiday Inn Express State College at Williamsburg Square Posted 11 hours ago Good hotel for business travel5 out of 5 Clean, comfy, spacious room. Nice gym and pool amenities for post work exercise. Easy to get to and convenient to nearby shops. Not too bad of a walk to downtown, about 1.5 miles. A verified traveler from Philadelphia, PA stayed at Courtyard by Marriott State College Posted 2 days ago Hide content
Where to stay in State College Hotel Class 1 star (2)2 stars (17)3 stars (18)4 stars (1) Near an Airport Blair CountyUniversity ParkMid-StateMifflin CountyCapital CityWilliamsport Regional Near an Attraction Pennsylvania State UniversityBald Eagle State ParkCity ParkBryce Jordan CenterBeaver StadiumNittany MallMyers ParkMessiah Lutheran ChurchRowland TheatreJuniata County CourthouseCurtin Village at Eagle IronworksPenn State Ice PavilionUnion Church and Burial GroundPenn State University's Blue and White Golf Courses Hotel Theme Adventure Sport Hotel (20)Arcade Hotel (2)Bar Hotel (50)Beach Hotel (2)Bed & Breakfast (9)Business Hotel (58)Conference Center Hotels (58)Family Hotel (55)Golf Hotel (34)Green/Sustainable (1)Historic Hotel (29)Hotel with Pool (47)Hotel with a Concierge (4)Hotel with wifi (73)Kid Friendly Hotels (55)Luxury Hotel (26)Pet-friendly Hotel (27)Romantic Hotel (6)Shopping Hotel (47)Ski Hotel (19)Spa Hotel (22)Wedding Hotels (18)Winery Hotel (29) Hotel Brand Best Western (1)Carlson (1)Choice (10)Hilton Worldwide (3)Hyatt Hotels (1)IHG (1)Independent (9)Magnuson Hotels (1)Marriott (4)Wyndham Worldwide (5)State College Hotel GuideTravelers to Central Pennsylvania are simply spoiled for choice when it comes to booking the perfect hotels in State College. About 25 hotels and apartments can be found within a 0.1-mile radius from State College's downtown area.The The Atherton Hotel, an Ascend Hotel Collection Member and Days Inn Penn State are some of the most central hotels in State College.With 2 Expedia-listed accommodation options, Bellefonte is the area with the largest selection of State College accommodations. Bellefonte is situated 11 miles from the center of town. The Riffles and Runs B & B and Econo Lodge Bellefonte are just some of the places to base yourself in and around Bellefonte.Burnham, Mifflintown and Boalsburg are some other State College areas that have accommodation options. In Burnham, the section of hotels include the Quality Inn & Suites and Super 8 Burnham Lewistown. Alternatively, if you base yourself in Mifflintown, you can make a selection between the Econo Lodge Mifflintown and Knights Inn Mifflintown. In Boalsburg visitors can make a selection between Springfield House and Springfield House Bed and Breakfast.State College offers a selection of economical accommodation options that will be sure to satisfy budget-minded vacationers and travelers. The Ramada State College Hotel and Conference Center is 1 mile from the heart of State College, while the Days Inn Penn State is 0.2 miles away. The Comfort Suites State College and the Quality Inn & Suites are alternative lower-cost places that you could consider.The Holiday Inn Express State College at Williamsburg Square can be found 2 miles from downtown State College. Another option is the Toftrees Golf Resort, which is positioned 3 miles away. The Best Western Plus University Park Inn & Suites and also the The Penn Stater Hotel and Conference Center are alternative hotel options in State College.Why don't you spread your wings and investigate the other sites dotted around Central Pennsylvania while you are in the area? Investigate Central Pennsylvania's traditional villages and art museums and photograph the area's rivers and rolling hills. Common activities in this part of United States of America include hiking and camping.DuBois is 50 miles to the northwest of State College and is home to the Sandy Township Recreational Park and Dubois Area Historical Society. Some of our recommended DuBois hotels are the Hampton Inn DuBois and Holiday Inn Express Hotel & Suites DuBois. 35 miles to the northwest of State College, is Clearfield, home to the Hampton Inn Clearfield and Comfort Inn Clearfield. The Lock Haven University Clearfield and Clearfield County Courthouse are a couple of the most popular points of interest to check out should you visit Clearfield.University Park Airport is situated 4 miles away from State College. Should you wish to stay close by, can book a night at the Carnegie Inn & Spa, an Ascend Hotel Collection Member or the Hampton Inn State College. Read More More Cheap Hotels in State College The Nittany Lion InnThe Penn Stater Hotel and Conference CenterCountry Inn & Suites State CollegeToftrees Golf ResortRamada State College Hotel and Conference CenterHyatt Place State CollegeDays Inn Penn StateBest Western Plus University Park Inn & SuitesQuality Inn Penn StateThe Atherton HotelSuper 8 State CollegeNittany Budget MotelSee a list of all hotels in State College Hotels Near State College, Pennsylvania Lewistown HotelsBellefonte HotelsCentre Hall HotelsPhilipsburg HotelsBoalsburg HotelsMilesburg HotelsHuntingdon HotelsMill Hall HotelsTyrone HotelsMilroy HotelsWoodward HotelsBurnham HotelsTipton HotelsReedsville HotelsHoward HotelsAlexandria HotelsWarriors Mark HotelsBelleville HotelsPetersburg HotelsSpring Mills Hotels Cheap Hotels in Other Destinations Hotels in Las VegasHotels in New YorkHotels in Los AngelesHotels in OrlandoHotels in ChicagoHotels in San DiegoHotels in San FranciscoHotels in Orange CountyHotels in MiamiHotels in WashingtonHotels in AtlantaHotels in DallasTravel to State College & ExploreExplore State College with Expedia's Travel Guides to find the best prices on flights, cars, vacation packages, and more!Flights to State CollegeCar Rentals in State CollegeState College VacationsThings to do in State College

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text:
A lucky Diwali for Mumbaikar | entertainment | Hindustan Times
A lucky Diwali for Mumbaikar
Updated: Nov 08, 2010 15:47 IST
Yesterday, I sneaked into Colaba Causeway in a gesture of solidarity with Colabakars trapped because of the Presidential visit. My first encounter was with an ordinary, humble, fifty-something, housewife.
Me: Ma’am, it must be the worst Diwali you’ve ever had...
She: Why? (gesticulating to workers) Be careful with that new 104’ TV! Place it in my bedroom. (to me) This is the greatest Diwali!
Me: But I thought it would be terrible for you! Being locked indoors for three days because of a pitiably paranoid security force…
She: Thank god for them! (to the workers) Arre! Careful with that Husain!
Me: What do you mean?She: Just day before yesterday, I was standing in my balcony when I saw a group of American commandos crying in pain. They were rolling and twisting in agony on the road. I asked them what the problem was. They explained that due to Obama’s visit, all public facilities had been closed down, including the toilets.
She: Arre, they hadn’t gone to the bathroom for 36 hours and were in agony!! I got an idea. I said you can use my bathroom for $100 a head. Then what! I made $25,000 in two days! (to workers) The Persian carpet in the bedroom!
I then met a shopkeeper and community leader. He was weeping outside his shut shop, brought to his knees because of misery and penury.
Me: Sir, I know what a blow this is. He kept weeping.
Me: A state visit during Diwali! I… His shoulders heaved, his body bent low, racked by sobs.
Me: Your livelihood’s been…
Shopkeeper (whispering): Shut up!
Shopkeeper: Shut up, you fool!
Me: I’m… I’m just trying to…
Shopkeeper: Stupid! Idiot! Look around you! Do you think anybody is crying? We are laughing, you fool! Laughing! Do you know why?
Sure enough. Under their bent heads, all the shopkeepers were actually cracking up with joy. Shopkeeper: Because there is no Obama! He never came!
Me: What! Now he raised his head and I could see him laughing his heart out. Tears of happiness streamed down his face.

value: This website is an Indian English-language daily newspaper introduced and founded in 1924 by Sunder Singh Lyallpuri, founder-father of the Akali movement and the Shiromani Akali Dal in the Punjab Province. It played integral roles in the Indian independence movement as a nationalist daily.


text:
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by 4einfovladislavko...
Apoyo para realizar diferentes proc...
C. Uma Maheswari, R. Meenakshi Reddy / International Journal of Engineering Research and
Vol. 3, Issue 4, Jul-Aug 2013, pp.617-622
Thermal Analysis of Thermal Energy Storage Systemwith Phase
C. Uma Maheswari*, R. Meenakshi Reddy**
*(Assistant Professor, Department of ME, SVCET, Chittoor, AP, India)
**( Professor, Department of ME, SVIT, Anantapur, AP, India)
Due to fast depletion of conventional
energy sources and ever increasing demand of
energy, many researchers started paying
attention to renewable energy sources.Thermal
Energy Storage (TES) is one of the key
technologies for energy conservation and has
recently been developed to a point where it can
have a significant impact on modern technologies.
The present work deals with the study of
a spherical container, filled with spheres
containing either paraffin wax or stearic acid as
Phase Change Materials (PCM) and water
occupying the space left between the spheres. The
ANSYS is used for modeling the PCM inside the
spheres with simple 2D model. Detailed thermal
analysis simulations of the solid liquid phase
change are performed. Simulations of the
charging and discharging modes are performed
and results obtained are compared against
previous theoretical results. The results are
compared for paraffin and stearic acid with
different sizes of the spheres and a fin inserted in
the sphere. It is observed that in these cases, the
time taken to complete the phase change in the
sphere changes as the size changes and paraffin
takes less time compared to stearic acid. When a
rectangular cross sectional copper fin is inserted
into the sphere radially the time taken is reduced,
hence output is increased.
Keywords - Phase change materials, paraffin,
Stearic acid, Thermal analysis, TES.
A lot of research work was carried out on
sensible heat storage (SHS) materials and systems in
the past and the technology for their utilization was
also well developed. Beasley and Clark have
provided an excellent review of such efforts in the
case of packed bed Sensible Heat Source (SHS)
systems[1]. Dincer et al. presented a detailed
investigation of the availability of SHS techniques
for solar thermal applications, selection criteria for
SHS systems, as well as the economics and
environmental impacts of SHS systems [2]. Thermal
performances of solar water heating systems
integrated with SHS system were investigated
experimentally [3, 4, 5].
Thermal energy storage using the latent heat concept
as an alternative to SHS offers a good option
because of its high storage density and the nearly
constant temperature heat storage and removal
characteristics during charging and discharging
processes. Several investigators have studied,
theoretically and experimentally, the performance of
thermal energy storage employing phase-change
material in a wide variety of geometries. Saitoh and
Hirose performed theoretical and experimental
investigation of the transient thermal characteristics
of a phase-change thermal energy storage unit using
spherical capsules [6]. Beasly et al. developed a
computational model to study the transient thermal
response of a packed bed of spheres containing a
phase change material usingone dimensional
separate phase formulation. Results from model
were compared with the experimental results of a
commercial size of the thermal storage bed packed
with polypropylene spheres containing paraffin wax
for both the energy storage and recovery periods
using air as heat transfer fluid [7]. Barba and spiga
analyzed the behavior of encapsulated salt hydrated
used as PCM in a heat transfer system of a domestic
hot water tank employing three different geometrical
configurations of the PCM containers. Their study
showed that spherical capsules yielded against the
slab or the cylindrical geometry [8]. Nallusamy et al
studied the thermal performance of a packed bed
latent heat thermal energy storage unit integrated
with solar water heating system. The experimental
results showed that the packed bed Latent Heat
Source (LHS) system reduced the size of the storage
tank appreciably when compared to conventional
storage system. The LHS system employing
batchwise discharging of hot water from the TES
tank is best suited for applications where the
requirement is intermittent[9]. Kalaiselvam et al.
analyzed the behavior of three paraffins, 60% n-
tetradecane + 40% n-hexadecane, n-tetradecane, and
n-pentadecane[10]. Ella Talmatsky and Abraham
Kribus studied annual simulations were done to
compare the performance of a storage tank with
PCM to a standard tank without PCM. A model was
constructed to describe the heat storage tank with
and without PCM [11]. Meenakshi Reddy et.al
studied the charging process of a spherical LHS
capsule with stearic acid, and paraffin as PCMs. His
experimental results demonstrated that, compared to
the stearic acid capsule, paraffin capsule melts
faster[12].
obtain the thermal-transient analysis of spherical
diameter of PCM capsules among three different
diameters (60, 50 and 40mm) for better efficiency of
sensible and latent heat thermal energy storage unit
integrated with constant heat source. Two different
materials stearic acid and paraffin, are used PCMs
for storing and retrieving the heat energy. Different
diameters of the high-density polyethylene (HDPE)
spherical capsules filled with PCM were used which
are always surrounded by a SHS material in the TES
tank. The water used as Heat Transfer Fluid(HTF) to
transfer heat from the constant temperature heat
source to TES tank also acts as SHS material.
Parametric studies are carried out to examine the
effects of the diameter when a copper fin is inserted.
setup is shown in Fig.1. This consists of an insulated
cylindrical TES tank, which contains PCM
encapsulated spherical capsules, solar flat plate
collector, flow meter and circulations pump. The
stainless steel tank has a capacity of 51 liters (360
mm diameter and 504 mm height) to supply hot
water for a family of 5 to 6 persons. Flow distributor
is provided on the top of the tank to make uniform
flow of HTF. The storage tank is insulated with
glass wool of 50 mm thick. The outer diameters of
spherical capsules are 60, 50 and 40mm and these
are made of HDPE with wall thickness of 2.50 mm
as shown in the Fig. 2.
The total number of capsules in storage
tank in case of paraffin and stearic acid for different
diameters are 152, 245 and 870 & 146, 235 and 836
respectively of 60, 50 and 40 mm to store the 10,000
KJ of heat. The spherical capsules are uniformly
packed in layers and each layer is supported by wire
mesh. The paraffin is used as PCM that has a
melting temperature of 61 ± 20
C and latent heat of
fusion of 213 KJ/Kg. Water is used as both SHS
material and HTF. Stearic acid is used as another
PCM that has a melting temperature of 57 ± 10
latent heat of fusion of 198 KJ/Kg.
A flow meter with accuracy of ±2% is used
to measure the flow rate of HTF and a centrifugal
pump is employed to circulate the HTF through the
storage tank. The TES tank is divided into four
segments i.e. at x/L =0.25, 0.5, 0.75 and 1.0 (L is
length of the TES tank, mm; x is the axial distance
from the top of the TES tank, mm; x/L is the
dimension less axial distance from the top of the
TES tank) along its axial direction and the
Resistance Temperature Detectors (RTD) with an
accuracy of ±0.30
C are placed at the inlet, outlet and
four segments of the TES tank to measure the
temperatures of HTF. Another four numbers of
RTDs are inserted into the PCM capsules and they
are placed at four segments of the TES tank to
measure the temperatures of PCM. The position and
number of RTDs are also designated in Fig.1. The
RTDs are connected to a temperature indicator,
which provides instantaneous digital outputs.
Fig.1 Schematic of Experimental set up
Different sizes of the Spherical capsules
made of HDPE are used as PCM containers as
spherical shape gives the best performance among
the various types of containers.
Fig. 2 Photographic view of different size of the
ANSYS 12 software is used to solve the
thermal- transient analysis. The tank was subdivided
in 24 sections (Nx=24). As in the simple 1D model,
only one sphere is simulated in each division,
assuming that all the spheres in a section have the
same behaviour. When the PCM inside the spheres
are changing phase, natural convection is produced
due to the difference between solid and liquid
densities and gravity action. Following assumptions
are made in the present work.
 Incompressible fluid
 Density is considered constant, except in
the gravity forces term.
 Constant thermo-physical properties
(properties of solid and liquid states are
assumed to be equal).
Fig. 3 Meshes of PCM sphere
Fig. 3 shows the meshed element of PCM
filled sphere which was analyzed for temperature
The results of simulating the charging and
discharging modes of operation of the thermal
energy accumulation system are presented in the
Fig. 5. Table 1 shows the different capsule
dimensions used for the analysis.
Table 1 Specifications of spherical diameters
In charging mode, the whole system is
initially at a uniform temperature of 200
water flow at 700
C starts entering the tank through
the top. Spheres, which were initially at solid state,
start to receive heat and eventually to melt.Figure 4
shows a detail of the liquid flow, enthalpy and
temperature maps of a representative sphere in the
first section of tank in charging mode, simulated
with the ANSYS model, with the finest mesh
considered. Natural convection phenomenon is
clearly identified.An ascending flow is induced by
the higher temperature of the fluid at the capsule
shell, arriving to the top of the sphere and then
descending to come into contact with the solid part.
The liquid flow transfers some of its heat of the
solid, getting cooler and descending along the solid
As the temperature of the capsule is higher
than the inner temperature also at the bottom of the
sphere, another ascending flow is generated here,
with an opposite spinning sense to the one of the
main flow. This flow produced a high heat transfer
rate locally, accelerating the melting process at the
bottom and deforming the initially spherical shape of
the solid portion.
Fig. 4 Nodal solutions of temperature map and
contours at initial condition
The resulting temperature map and solid
shape are appreciably different from the concentric
ones that would be obtained if the convection were
not present. It should be noted that, in this work,
forces acting on the solid have not been considered.
These tend to bring the solid portion down to the
bottom of the capsule at some moment of the
melting deviating its evolution from the described by
our model. These effects should be considered in
The numerical results of the simulations of
the spheres are presented in the Figures, where
simplified analysis for constant phase change
temperature is included.
(a) After 0.39 minutes
(b) After 1.339 minutes
(C) After 1.67 MINUTES
(d) After 2.336 minutes
(e) After 2.668 minutes
(f) After 3 minutes
Fig. 5 Temperature distribution stages of Paraffin
Figure 5 shows the simulations obtained at
different time steps. The figures 5 (a) to (f) shows
the temperature distribution from heat transfer fluid
towards the centre of the node in the PCM sphere.
The time taken to complete the temperature
distribution is noted for different size of the spheres
and for different PCM materials such as paraffin and
stearic acid. The values are tabulated and
comparison study is made.
Fig. 6 Meshed model of fin type PCM sphere
Figure 6 shows the meshed model of a
PCM sphere when a copper fin is inserted in to it
radially which increases the speed of temperature
Table 2 Comparison of temperature distribution in
Paraffin wax Stearic acid
1 60 mm 3 min 3.5 min
2 50 mm 2 min 2.5 min
3 40 mm 1.2 min 1.55 min
2.724 min 3.2 min
Comparing the three different sizes of
spheres, the time taken for full phase change is
tabulated as follows in Table 2.
Fig. 7 Comparison of time taken for different sizes
Figure 7 shows the graph of time taken to
complete the phase change for different size of the
spheres with and without fin. It is observed from the
from the Fig. 7 that in these cases, the time taken to
complete the phase change in the sphere, changes as
the size changes and paraffin takes less time
compared to stearic acid. When a rectangular cross
sectional copper fin is inserted into the sphere
radially the time taken is reduced, hence output is
Fig. 8 Temperature profiles for different sphere sizes
Figure 8 shows the temperature distribution
of different sizes of balls. It is seen from the Fig. 8
that the phase change occurs at a constant
temperature in the theoretical predictions whereas a
near constant temperature is observed in the
experimental investigation. The reason is that the
PCMs do not have single melting point and they
melt normally over a temperature range. It is already
mentioned that the paraffin and stearic acid which is
used as PCM in the present investigation, has the
melting temperature in the range of 590
C to 610
The temperature rise in the experimental results is
lower than the numerical predictions after the
complete melting of PCM at any segment. This is
due to the higher specific heat value of the liquid
PCM in the actual case than the value provided in
the numerical computation.
Fig. 9 Theoretical and experimental temperature
Figure 9shows the comparison of
theoretical and experimental temperature histories of
the PCM in the TES tank for the case of constant
HTF inlet temperature. It is observed from the Fig. 7
that the experimental values are slightly lower than
the theoretical values during most of the charging
period as in constant HTF inlet temperature case. A
small temperature difference between theoretical and
experimental values is found. It is due to the
limitations of the maximum temperature obtainable
in the experiment (70 – 73 0
C) due to the type of
heat source used whereas in the theoretical analysis a
linear increase in heat flux is observed that increases
the HTF inlet temperature linearly with time.
During the melting process all the
numerical methods give almost the same results for
the temperature of the PCM when the PCM is in a
solid state. First of all the PCM starts to melt when
the effective heat capacity method with a wide
temperature range is used. The melting starts at
C. The PCM melts a little too quickly when the
experimental and theoretical results are compared.
All the numerical results compare quite well to the
experimental results of the temperature of the PCM.
During the solidification process all the
theoretical methods give uniform results for the
temperature of the PCM in a liquid state. When
solidification begins the effective heat capacity
method with a wide temperature range gives almost
the same results as the enthalpy method.The
phenomena which were observed in the storage
without fin can also be seen in the results from the
storage with the fin. During the melting process the
theoretical method gives the most precise results for
the temperature of the PCM in the middle of the
storage. At the sides of the storage the PCM melts
One reason for the difference between the
theoretical and experimental results in the material
properties of the PCM is assumed that the density
60 50 40 60 mm +
size of the sphere
Time taken to complete Paraffin wax
Time taken to complete Stearic acid
Temperatureinkelvin
60 mm 50 mm 40 mm
and the heat conductivity of the PCM are constant. If
the temperature dependent material properties are
known, the theoretical methods will give more
precise results for the temperature of the PCM.
Thus, the material properties of the PCM should be
well known in order to obtain sufficiently accurate
results with the numerical methods.Another reason
for the differences between the theoretical and
experimental results may be in the placement of the
thermocouples. The storage is filled with the liquid
PCM. The placement of the thermocouple may have
been slightly changed. After the storage is filled up
it is impossible to check the placement of the
A thermal energy storage system has been
developed for the use of hot water at an average
temperature of 450
C for domestic applications using
combined sensible and latent heat storage concept.
Charging experiments are conducted on the TES unit
to study its performance by integrating it with
constant heat source. The temperature histories of
HTF & PCM and energy storage characteristics
during charging process for various size of capsules
(60mm,50mm and 40mm) and different PCMs
(Paraffin and stearic acid) are studied.
Detailed thermal-transient analysis
simulations of the solid liquid phase change are
performed. Simulations of the charging modeis
performed and results obtained are compared against
previous results and found that they are closely
related with experimental methods. The results are
compared for paraffin and stearic acid with different
sizes of the spheres and a fin inserted in the sphere.
It is observed that in these cases, the time taken to
complete the phase change in the sphere changes as
increased. The quantity of water discharged is also is
almost same in paraffin and stearic acid, with slight
variation of 3-4%. This is because of latent heat,
thermal conductivity and specific heat quantities for
both PCMs are almost same with 5-7% variation.
But the cost of stearic acid is around Rs.48 per kg
where as paraffin cost is Rs.75 in the Indian market.
So economically the stearic acid is going to give the
same output at less initial cost. Hence stearic acid is
best option for Thermal Energy Storage System.
[1] Beasley. D.Eand Clark. J.A, Transient
response of a packed bed for thermal
energy storage,International Journal of
Heat& Mass Transfer, 27(9), 1984, 1659-
[2] Dincer.I, Dost. S andXianguo. L,
Performance analysis of sensible heat
storage systems for thermal applications,
21, 1997, 1157-1171.
[3] Collares-Pereira. M, Gordon. J.M, Rabl. A
andZarmi. Y, Design and optimization of
solar industrial hot water systems with
storage, Solar Energy, 32(1), 1984, 121-
[4] Sodha. M.S, Sharma. A.K, Sawhney. R.L
and Kumar. A, Experimental performance
of built-in-storage solar water heating
systems in laboratory and field conditions,
21, 1997, 275-287.
[5] Reddy. K.S, Avanti. P andKaushika. N.D,
Finite time thermal analysis of ground
integrated-collector-storage solar water
heater with transparent insulation cover,
23, 1999, 925-940.
[6] Saitoh. T and Hirose. K, High performance
phase-change thermal energy storage using
spherical capsules, Chemical Engineering
Communication, 41, 1986, 39-58.
[7] Beasley. D.E andRamanarayanan. C,
Thermal response of a packed bed of
spheres containing a phase change material,
13, 1989, 253-265.
[8] Barba. AandSpiga. M, Discharge mode for
encapsulated PCMs in storage tanks, Solar
energy, 74(2), 2003, 141-148.
[9] Nallusamy. N, Sampath. S and Velraj. R,
Study on performance of a packed bed
latent heat thermal energy storage unit
integrated with solar water heating systems,
Journal of Zhejiang University science A,
7(8), 2006, 1422-1430.
[10] Kalaiselvam. S, Veerappan. M, Arul
Aaron.A and Iniyan. S, Experimental and
analytical investigation of solidification and
melting characteristics of PCMs inside
cylindrical encapsulation, International
Journal of Thermal Sciences, 47, 2007,
858–874.
[11] Ella Talmatskyand Abraham Kribus, PCM
storage for solar DHW: An unfulfilled
promise?,Solar Energy ,82, 2008, 861-869.
[12] Meenakshireddy. R,Nallusamy. N,
Anjaneya Prasad. B and Hema Chandra
Reddy. K., Thermal energy storage system
using phase change materials: constant heat
source, International Journal of Thermal
Sciences, 16(4), 2012, 1097-1104.

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text: Patent US7826826 - Apparatus, and associated method, for facilitating routing of data in a ... - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inPatentsApparatus, and an associated method, for providing routing information to a mobile node operable in a radio communication system. The routing information is used by the mobile node to address data messages that are to be communicated to a relay host, or other, device. The routing information that is...http://www.google.com/patents/US7826826?utm_source=gb-gplus-sharePatent US7826826 - Apparatus, and associated method, for facilitating routing of data in a radio communication system having a mobile node capable of roaming movementAdvanced Patent SearchTry the new Google Patents, with machine-classified Google Scholar results, and Japanese and South Korean patents.Publication numberUS7826826 B2Publication typeGrantApplication numberUS 12/628,638Publication dateNov 2, 2010Filing dateDec 1, 2009Priority dateFeb 19, 2004Fee statusPaidAlso published asUS7362730, US7650141, US8036640, US8351902, US8923819, US20050185616, US20080153485, US20100074186, US20110044252, US20110317618, US20130170412Publication number12628638, 628638, US 7826826 B2, US 7826826B2, US-B2-7826826, US7826826 B2, US7826826B2InventorsIan M. Patterson, Richard Betel, Adrian Rogobete, Ken AxtmannOriginal AssigneeResearch In Motion LimitedExport CitationBiBTeX, EndNote, RefManPatent Citations (10), Referenced by (5), Classifications (12), Legal Events (3) External Links: USPTO, USPTO Assignment, EspacenetApparatus, and associated method, for facilitating routing of data in a radio communication system having a mobile node capable of roaming movement

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