WO2014022844A2 - In-vacuum high speed pre-chill and post-heat stations - Google Patents

In-vacuum high speed pre-chill and post-heat stations Download PDF

Info

Publication number
WO2014022844A2
WO2014022844A2 PCT/US2013/053567 US2013053567W WO2014022844A2 WO 2014022844 A2 WO2014022844 A2 WO 2014022844A2 US 2013053567 W US2013053567 W US 2013053567W WO 2014022844 A2 WO2014022844 A2 WO 2014022844A2
Authority
WO
WIPO (PCT)
Prior art keywords
workpiece
station
post
temperature
chill
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US2013/053567
Other languages
French (fr)
Other versions
WO2014022844A3 (en
Inventor
William Lee
William Reynolds
Stanley STONE
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Axcelis Technologies Inc
Original Assignee
Axcelis Technologies Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Axcelis Technologies Inc filed Critical Axcelis Technologies Inc
Priority to KR1020157005135A priority Critical patent/KR102126367B1/en
Priority to JP2015525641A priority patent/JP6267201B2/en
Priority to CN201380041167.6A priority patent/CN104685604B/en
Publication of WO2014022844A2 publication Critical patent/WO2014022844A2/en
Publication of WO2014022844A3 publication Critical patent/WO2014022844A3/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/02—Details
    • H01J37/18—Vacuum locks ; Means for obtaining or maintaining the desired pressure within the vessel
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/02—Details
    • H01J37/20—Means for supporting or positioning the object or the material; Means for adjusting diaphragms or lenses associated with the support
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/30—Electron-beam or ion-beam tubes for localised treatment of objects
    • H01J37/317—Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. for ion implantation
    • H01J37/3171—Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. for ion implantation for ion implantation
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/04—Apparatus for manufacture or treatment
    • H10P72/0431—Apparatus for thermal treatment
    • H10P72/0434—Apparatus for thermal treatment mainly by convection
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/04—Apparatus for manufacture or treatment
    • H10P72/0451—Apparatus for manufacturing or treating in a plurality of work-stations
    • H10P72/0466—Apparatus for manufacturing or treating in a plurality of work-stations characterised by the construction of the load-lock chamber
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/04—Apparatus for manufacture or treatment
    • H10P72/0451—Apparatus for manufacturing or treating in a plurality of work-stations
    • H10P72/0468—Apparatus for manufacturing or treating in a plurality of work-stations comprising a chamber adapted to a particular process
    • H10P72/0471—Apparatus for manufacturing or treating in a plurality of work-stations comprising a chamber adapted to a particular process comprising at least one ion or electron beam chamber
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/30—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for conveying, e.g. between different workstations
    • H10P72/33—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for conveying, e.g. between different workstations into and out of processing chamber
    • H10P72/3302—Mechanical parts of transfer devices
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P72/00—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof
    • H10P72/30—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for conveying, e.g. between different workstations
    • H10P72/34—Handling or holding of wafers, substrates or devices during manufacture or treatment thereof for conveying, e.g. between different workstations the wafers being stored in a carrier, involving loading and unloading
    • H10P72/3402—Mechanical parts of transfer devices
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/20—Positioning, supporting, modifying or maintaining the physical state of objects being observed or treated
    • H01J2237/2001—Maintaining constant desired temperature
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/20—Positioning, supporting, modifying or maintaining the physical state of objects being observed or treated
    • H01J2237/2002—Controlling environment of sample
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/20—Positioning, supporting, modifying or maintaining the physical state of objects being observed or treated
    • H01J2237/2007—Holding mechanisms
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/20—Positioning, supporting, modifying or maintaining the physical state of objects being observed or treated
    • H01J2237/201—Positioning, supporting, modifying or maintaining the physical state of objects being observed or treated for mounting multiple objects
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/20—Positioning, supporting, modifying or maintaining the physical state of objects being observed or treated
    • H01J2237/204—Means for introducing and/or outputting objects
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/30—Electron or ion beam tubes for processing objects
    • H01J2237/317—Processing objects on a microscale
    • H01J2237/31701—Ion implantation
    • H01J2237/31705—Impurity or contaminant control
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
    • H10P90/00—Preparation of wafers not covered by a single main group of this subclass, e.g. wafer reinforcement

Definitions

  • the present invention relates generally to ion implantation systems, and more specifically to preventing condensation from forming on a wor (piece in an ion implantation system.
  • Electrostatic clamps or chucks are often utilized in th ⁇
  • a typical ESC for example, comprises a dielectric layer po sitioned over a conductive electrode, wherein the semiconductor wafer is placec Dn a surface of the ESC (e.g., the wafer is placed on a surface of the dielectric layer).
  • a clamping volta:je is typically applied between the wafer and the electrode, wherein the wafer is clamped against the chuck surface by electrostatic forces.
  • cooling the workpieo via a cooling of the ESC is desirable.
  • condensation can form on the workpiece, or even freezing of atmospheric water on thu surface of the workpiece can occur, when the workpiece is transferred from tho cold ESC in the process environment (e.g., a vacuum environment) to an external environment (e.g., a higher pressure, temperature, and humidity environment).
  • the process environment e.g., a vacuum environment
  • an external environment e.g., a higher pressure, temperature, and humidity environment.
  • the load lock ch amber is subsequently is vented.
  • the load lock chamber is opened tc emove the workpiece therefrom, the workpiece is typically exposed to ambient atmosphere (e.g., warm, "wet" air at atmospheric pressure), wherein condensation can occur
  • the condensation can deposit particles on the workpiece, and/or leave residues on the workpiece that can have adverse effects on front side particles (e.g., on active areas), and can lead to defects and ptoduction losses.
  • Heating of the workpiece can be performed in order to attenot to alleviate the adverse effects of condensation; however, such heating often 'soaks" the workpiece for a period of time on the ESC in order to reach a predsitermined temperature, prior to transferring the wafer. Long soak times conv ⁇ ; ntiona!ly adversely affect workpiece throughput in the ion implantation system.
  • the present invention overcomes the limitations of the prior ;.rt by providing a system, apparatus, and method for abating condensat ion on a workpiece and maintaining reasonable process throughput in a chil ed ion implantation system. Accordingly, the following presents a simplified summary of the disclosure in order to provide a basic understanding of some a;; pects of the invention. This summary is not an extensive overview of the inversion. It is intended to neither identify key or critical elements of the invention lor delineate the scope of the invention. Its purpose is to present some concept;; of the invention in a simplified form as a prelude to the more detailed de3 ⁇ 4;t:ription that is presented later.
  • an ion implantat c n system for implanting ions into a cold workpiece comprises an ion implantation apparatus configured to provide a plurality of ions to a workpiece positioned in a process chamber, wherein the process chamber has a process environment associated therewith.
  • a sub-ambient temperature chuck such as a cryogenically cooled electrostatic chuck, is configured to support the workpiece within tliu process chamber during an exposure of the workpiece to the plurality of ions.
  • the cryogenic chuck is further configured to cool the workpiece to a pr messing temperature, wherein the process temperature is below a dew poin : of an external environment.
  • a load lock chamber is provided, wierein the load lock chamber is operably coupled to the process chamber and is configured to isolate the process environment from the external environment.
  • the load lock chamber further comprises a workpiece support configured to support the workpiece during a transfer of the workpiece between the process chamber and the intermediate chamber.
  • a pre-chill station is further positioned within the process chamber, wherein the pre-chill station comprises a chilled workpiece support configured to cool the workpiece to a first temperature.
  • the firsc temperature is significantly lower than the process temperature.
  • the pre-chill station for example, comprises a cooling plate configured to support the worl iece and to cool the workpiece to the first temperature.
  • a pressure of the pre-chill gas for example, generally determines a fooling of the workpiece.
  • a post-heat station is also positioned within the process chamber, wherein the post-heat station comprises a heated workpiece support config -ired to heat the workpiece to a second temperature.
  • the post-heat station comprises a heating station support comprising a heating plate cci figured to support the workpiece and to heat the workpiece to the second temperature.
  • the post-heat station further comprises a post-ht:at gas sealing ring configured to support a periphery of the workpiece, a post-heEit clamp configured to maintain a position of the workpiece on the heated workpiece support, and a post-heat gas source configured to provide a post- uat gas between a gas heating space defined between the workpiece and a surface of the heated workpiece support. Accordingly, a pressure of the posl eat gas generally determines a heating of the workpiece.
  • the chuck is diametrically opposed to the lo:id lock chamber within the vacuum chamber, and the pre-chill station is dii; metrically opposed to the post-heat station within the vacuum chamber.
  • the chilled workpiece holding E;tation is positioned within the process chamber, wherein the chilled workpi e holding station comprises a cold workpiece support configured to support li e workpiece when the workpiece is at the first temperature.
  • a heated workpiecEi holding station may be further positioned within the process chamber, wheoin the heated workpiece holding station comprises a hot workpiece suppol configured to support the workpiece when the workpiece is at the second temperature.
  • the chuck is diametrically opposed to the load lock chamber
  • the pre-chill station is diametrically opposed to the post-heat station
  • the chilled workpiece holding station is diametrically opposed to the he;ited workpiece holding station within the vacuum chamber.
  • a workpiece transfer arm is configured to concurrently transfer two or more workpieces between two or more of the chuck, load lock chamber, pre-chill station, and post-heat station.
  • the workpiece transfer arm for example, comprises two pairs of workpiece transfer clamps positioned approximately 90 degrees from one another, wherein each pair of workpiece transfe * clamps is diametrically opposed to each other.
  • Each pair of workpiece transfer clamps is configured to concurrently grasp or release a workpiece from the cl uck and load lock chamber, from the pre-chill station and post-heat station, and c:r the chilled workpiece holding station and heated workpiece holding station, b ; 3 sed on a rotational position of the workpiece transfer arm.
  • a controller may be further configured to determine the first temperature and the second temperature, based, at least in part, on a desired process throughput.
  • a temperature monitoring system for example, is conf gured to measure a temperature of the workpiece at the pre-chill station and the post-heat station. The controller is thus further configured to control cooling cf the workpiece to the first temperature and the heating of the workpiece to the second temperature, based, at least in part, on the measured temperature of the workpiece.
  • a method fo ⁇ implanting ions into a workpiece at sub-ambient temperatures is provided.
  • a vrorkpiece is provided in an external environment at an external temperature anc external pressure and transferred from the external environment to the load lock chamber.
  • the pressure within the load lock chamber is lowered to a substantial vacuum, and the workpiece is transferred from the load lock chamber to the Dre-chill for cooling.
  • the pre-chill station for example, is cooled to the first tern Derature that is lower than a process temperature, thus quickly cooling the work:>:ece.
  • the workpiece is then transferred from the pre-chill station to the chuck that is cooled to the process temperature.
  • Ions are implanted into the workpiece via an ion implantation apparatus, and the workpiece is subsequently transferred from the chuck to ti n;: post-heat station within the vacuum environment.
  • the workpiece is heated ⁇ il the post-heat station, wherein the post-heat station is heated to the second temperature that is greater than the external temperature, therein quickly heating the WDrkpiece.
  • the workpiece is then transferred from the post-heat station to the bad lock chamber, the pressure within the load lock chamber is increased to the external pressure, and the workpiece is removed from the load lock chambi'.
  • the workpiece is transferred from the load ic.ck chamber to the pre-chill station occurs while concurrently transferring anothu " workpiece from the chuck to the post-heat station.
  • the workpiece is transferred from the pre-chill station to the chuck occurs while concurrently transferring another workpiece from the post-heat station to the load lock chamber.
  • transferring the workpiece from the pre- hill station to the chuck comprises transferring the workpiece from the pre-chill st ation to the chilled workpiece holding station, and then transferring the workpiece from the chilled workpiece holding station to the chuck, while transferring the workpiece from the post-heat station to the load lock chamber comprises transferring the workpiece from the post-heat station to the heated workpiece holdirg station, and then transferring the workpiece from the heated workpiece holding station to the load lock chamber.
  • Such transfers permit concurrent transfers of f jr workpieces via the workpiece transfer arm in a logical and through jt-sensitive manner.
  • Fig. 1 is a block diagram of an exemplary vacuum system comprising an ion implantation system in accordance with several aspects of the prssent disclosure.
  • Fig. 2 is a cross-sectional view of an exemplary pre-chill station in accordance with another aspect of the disclosure.
  • Fig. 3 is a cross-sectional view of an exemplary post-heat s ; tion in accordance with yet another aspect of the disclosure.
  • Fig. 4 illustrates a process chamber in accordance with ano tier exemplary aspect of the disclosure.
  • Figs. 5A and 5B illustrate an exemplary workpiece transfer ai m in respective open and closed positions in accordance with still anotht; r aspect of the disclosure.
  • Fig. 6 is a schematic view of another exemplary process chamber in accordance with another aspect of the disclosure.
  • Fig. 7 illustrates an exemplary flow of workpieces through a chilled ion implantation system in accordance with another aspect of the disclo sure.
  • Fig. 8 illustrates a methodology for implanting ions into a workpiece at sub-ambient temperatures, in accordance with to still another aspect.
  • the present disclosure is directed generally toward a systei apparatus, and method for abating condensation on a workpiece and maintain ing
  • any connection which is described as being wire-based in the following specification may also be implemented as a wireless communication, unless nolcd to the contrary.
  • Fig . 1 illustrates an exemplary vacuum system 100.
  • the vacuum system 100 in the present example comprises an ion implantation system 101 , however variou 5 other types of vacuum systems are also contemplated, such as plasma proces s ng systems, or other semiconductor processing systems.
  • the ion implantation i;/stem 101 for example, comprises a terminal 102, a beamline assembly 104, and an end station 106.
  • an ion source 108 in the terminal 102 in coupled to a power supply 1 10 to ionize a dopant gas into a plurality of ions and to form an ion beam 112.
  • the ion beam 112 in the present example is directed th Dugh a beam- steering apparatus 114, and out an aperture 116 towards the end :s ation 106.
  • the ion beam 1 12 bombards a workpiece 118 O.g., a semiconductor such as a silicon wafer, a display panel, etc.), which is selectively clamped or mounted to a chuck 120 (e.g., an electrostatic chuck o - ESC).
  • a chuck 120 e.g., an electrostatic chuck o - ESC.
  • the implanted ions hange the physical and/or chemical properties of the workpiece. Because of this, ion implantation is used in semiconductor device fabrication and in met al finishing, as well as various applications in materials science research.
  • the ion beam 1 2 of the present disclosure can take any form, such as a pencil or spot beam, a ribbon beam, a scanned beam, or any other form in which ions are directed toward end station 106, and all such forms are ccintemplated as falling within the scope of the disclosure.
  • the end station 06 comprises a process chamber 122, such as a vacuum chamber 124, wherein a process environment 126 is associated with the process chamber.
  • the prcc ess environment 126 generally exists within the process chamber 122, .and in one example, comprises a vacuum produced by a vacuum source 28 ( ?.g., a vacuum pump) coupled to the process chamber and configured to substantially evacuate the process chamber.
  • energy can build up on the workpiece 1 18 in the form of heat, as the charged ions collide with the workpiece. Absent countermeasures, such heat can poteir ially warp or crack the workpiece 18, which may render the workpiece worthier,!; (or significantly less valuable) in some implementations.
  • the heat can xirther cause the dose of ions delivered to the workpiece 118 to differ from the d sage desired, which can alter functionality from what is desired.
  • the chuck 120 cc mprises a sub-ambient temperature chuck 130, wherein the sub-ambient temperature chuck is configured to both support and cool or otherwise maintain ;
  • the chuck 20 is referred to in the present example! as being the sub-ambient temperature chuck 130, the chuck 120 can likewise comprise a super-ambient temperature chuck (not shown), wherein the super-?; mbient temperature chuck is configured to support and heat the workpiec 1 18 within the process chamber 122.
  • the sub-ambient temperature, chuck 130 is an electrostatic chuck configured to cool or chill the workpiece 118 to a processinci :emperature that is considerably lower than an ambient or atmospheric tempers lure of the surroundings or external environment 132 ⁇ e.g., also called an "atmospheric environment").
  • the super-ambient temperature chuck may comprise an electrostatic chuck configured to heat the workpiece 8 to a processing temperature that is considerably higher than the an bient or atmospheric temperature of the surroundings or external environmc nt 132.
  • a cooling system 134 may be further provided, wherein, in another example, the cooling system is configured to cool or chill the sub-ambient temperature chuck 130, and thus, the workpiece 118 residing thereon, to the processing
  • a heatir g system (not shown) may be further provided in the case of a super-ambient temperature chuck, wherein the heating system is configured to heat the super- ;;imbient temperature chuck and workpiece 118 residing thereon to the proc ssing temperature.
  • l e processing temperature is be!ow the ambient dew point (e.g., 8 degrees C, al:» called dew point temperature) of the external environment 132, such as a processing temperature of approximately -40 degrees C.
  • the present disclosure thus provides a pre-chill station 36 positioned within the vacuum environment 126 of the process chamber 120.
  • the pre-chill station 136 for example, comprises a chilled workpiece support 138, as illustr ted further in Fig. 2, wherein the chilled workpiece support 38 is configured to cool the workpiece to a first temperature.
  • the chilled workpiece support 138 for example, comprises ;3 thermal pad 140, such as a cooling plate 142, wherein the thermal pad is configured to support the workpiece and to cool the workpiece to the first tempe rature.
  • the thermal pad 140 for example, comprises a cooling plate 142 comprising one or . more of a peltier cooler, an expansion chamber, a cryogenic head, and a circulatory refrigeration loop.
  • the pre-chill station 136 of Fiy 1 further comprises a pre-chill gas sealing ring 144, as illustrated again in Fig. 2, wherein the pre-chill gas sealing ring is generally disposed about a perimeter of the chilled workpiece support 138.
  • the pre-chill gas sealing ring 144 or example, is configured to support a periphery 146 of the workpiece 118, and t:i generally provide a seal between the workpiece and the chilled workpiece si. pport 138.
  • a pre-chill clamp 148 is further provided, wherein the pre-chill clamp is configured to maintain a position of the workp ece 1 18 on the chilled workpiece support 138. As illustrated again in Fig.
  • a f>re-chill gas source 150 is further provided, wherein the pre-chill gas source is configured to provide a pre-chill gas 152 between a gas cooling space 154 illustrated in Fig. 2, wherein the gas cooling space is defined between the workpiece 1 ' 8 and a surface 156 of the chilled workpiece support 138.
  • a pres ure of the pre- chill gas 152 within the gas cooling space 154 is configured to generally determine a cooling of the workpiece 1 18.
  • the rate of heat transfer between the workpiece 118 and tri ⁇ ; chilled workpiece support 138 is generally proportional to the temperature difference between the workpiece and the chilled workpiece support.
  • T(t) T ⁇ + (To - e W (1)
  • T(t) is the temperature of the workpiece 18 being cooled or heated as a function of time
  • T ⁇ is the temperature of object doing the cooling oi heating, which in this case, sit he chilled workpiece support 138
  • T 0 is the inkial temperature of the workpiece
  • e is the Euler number (2.71828%)
  • t is time
  • ⁇ a time constant which depends, among other factors, on the heat transfer coefficient. As will be understood from equation (1 ), it is substantia ly quicker to get the workpiece 118 to a predetermined temperature when the t, nperature of the chilled workpiece support 138 is overdriven to a first temperature that is lower than the processing temperature.
  • the first tempera ture is at least an order of magnitude lower than the process temperature, lor example, if a process temperature of -40C is desired, it would take many time tOnstants to be acceptably close to -40C if the chilled workpiece support 138 we re held at - 40C. However, if the chilled workpiece support 138 is driven to a first
  • the ch ' lled workpiece support 138 is configured to cool at the first temperature wherein the first temperature is significantly lower than the desired processing temperature.
  • the post-heat station 58 c:f Fig. 1 is further positioned within the vacuum environment 126 of the proce s chamber 122, wherein the post-heat station further comprises a heated workpiece support 160, as illustrated in Fig. 3, configured to heat the workpiece 118 to a second temperature.
  • the heated workpiece support 160 for example, com arises another thermal pad 140, such as a heating plate 161 , wherein the thermal pad is configured to support the workpiece and to heat the workpiece to tin. second temperature.
  • the post-heat station 158 for example, further comprises a post- heat gas sealing ring 162, wherein the post-heat gas sealing ring is.
  • the post- heat gas sealing ring 162 is configured to support the jeriphery 146 of the workpiece 118, and to generally provide a seal between the w orkpiece and the heated workpiece support 160.
  • a post-heat damp 166 is further provided, wherein the post-heat clamp is configured to maintain a position of ie workpiece 118 on the heated workpiece support 160.
  • a post- heat gas source 168 is further provided, wherein the post-heat gas i;ource is configured to provide a post-heat gas 170 between a gas heating ⁇
  • a pressure of the post-heat gas 170 within the gas heating space 172 is configured to generally determine a heating of the workpiece 118.
  • heating of the workpiece 118 in the post-heat station 158 of Fig. 1 can be overdriven, wherein the seccr d
  • the post-heat station 15.! and pre-chill station 136 are generally isolated from one another within the proos >s chamber 122, wherein heat transfer between the post-heat station and pre-cNII station is minimized.
  • the second temperature is no greater than 100C to approximately 150C, wherein stability of a conventional photoresisi: Degins to decay.
  • a temperature monitor ng system 176 is further provided, and configured to measure a temperature ⁇ :f the workpiece 118 at the pre-chill station 136 and the post-heat station 158, as illustrated in Fig. 4.
  • the temperature monitoring system 176 for e :> ample, comprises one or more workpiece temperature monitoring devices: 78A, 178B configured to measure a temperature of the workpiece 1 18 residing on the respective pre-chill station 136 and the post-heat station 58, thus nonitoring the temperature of the workpiece during cooling and heating thereof, a id improving process efficiencies.
  • a controller 180 illustrated in Fig. 1 is further configured to control cooling of the workpiece 1 18 to the first temp* rature and the heating of the workpiece to the second temperature, based, at least in part, on the measured temperature of the workpiece.
  • a load lock chamber 182 is further operably coupled to the process chamber ⁇ : 2, wherein the load lock chamber is configured to isolate the process environment 126 from the external environment 132.
  • the load lock chamber 182 further comprises a workpiece support 184 configured to support the workpiece 118 du 'ing a transfer of the workpiece between the process chamber 122 and the extern al
  • a plurality of load lock doors 186A, 186B operably couple the load lock chamber 182 to the respective process chamber 122 and the external environment 132.
  • One or more auxiliary transfer arms 189 may be further provided to assist in transferring workpieces, in accordance with another example.
  • the workpiece transfer arm 188 as illustrated in greater detail in Fig. 4, comprise.: two pairs 190A, 190B of workpiece transfer clamps 192A, 192B positioned approximately 90 degrees from one another, wherein each pair of workpiece transfer clamps is diametrically opposed to each other.
  • Each pair 190A, 190B of wci piece transfer clamps 192A, 192B is configured to concurrently grasp or release a workpiece 118 from the chuck 120 and load lock chamber 182, or Inm the pre- chill station 136 and post-heat station 158, based on a rotational position of the workpiece transfer arm 88.
  • the workpiece transfer arm 188 has the ability to rotate
  • T workpiece transfer arm 188 is part of an assembly (not shown) o>mprised of two arms that rotate together and can be opened and close like sc !i sors, in order to effectuate gripping and releasing workpieces 118.
  • Fig. 5A illustrates the two pairs 190A, 190B of workpiece transfer clamps ' !2A, 192B in an open position 193A, wherein the workpiece transfer clamps are operable to generally surround, but not contact the two or more workpieces 11 i: .
  • the workpiece transfer clamps 192A, 192B are in a closed position 193B, wherein the workpiece transfer clamps are position id to contact and concurrently grip the two or more workpieces 18.
  • a chilled workpiece holding station 194 is positioned within the process chamber 122, wherein the chilled workpiece holding station comprises a co t: workpiece support 196 configured to support the workpiece 1 18 once the wc piece is at the first temperature in the pre-chill station 136.
  • the cold workpie:;3 support 196 for example, is further configured to maintain the temperature of thi3 ⁇ 4 workpiece 1 18 while the workpiece resides on the cold workpiece support 1 S ⁇ : .
  • a heated workpiece holding station 198 is further positioned within the proc ss chamber 122, wherein the heated workpiece holding station comprises a hoi workpiece support 199 configured to support the workpiece 8 when the woikpiece is at the second temperature.
  • the hot workpiece support 199 for exair pie, is further configured to maintain the temperature of the workpiece 118 whilii the workpiece resides on the hot workpiece support 199.
  • the chuck 120 is diametrically opposed to the load lock chamber 182
  • the pre-chill station 136 is diametrically opposed to the post-heat station 158
  • the chilled workpiece holding station 194 is diametrically opposed to the heated workpiece holding station 198 within the process chamber 122.
  • various other configurations and locations of the chuck 120, load lock chamber 182, pre-chill sta tion 136, post-heat station 158, chilled workpiece holding station 194, and h eated workpiece holding station 198 within the process chamber 122 are; contemplated as falling within the scope of the present disclosure.
  • :he chilled workpiece holding station 194 may be positioned opposite the pre -chill station 136, and the heated workpiece holding station 198 may be positioned opposite the post-heat station 158.
  • Such a configuration may provide an advantageous flow of workpieces 1 18, depending on the configuration of the wor kpiece transfer arm 188.
  • the load lock chamber 182 is illustrated as being within the process chamber 122; however, it should be understood that the load lock door 186A of Fig. 4 operably couples the load lock chamber 1 ii2 to process chamber.
  • a sub-ambient implantatio i e.g., an implantation at a temperature below ambient temperature
  • the workpiece 1 18 is transferred to the pre-chill station 136, wherein the workpiece is pro-chilled to approximately the processing temperature.
  • the workpiece 1 18 is either transferred to the chuck 1 20 for appropriate implantation of ions according to process requirements., or transferred to the chilled workpiece holding station 194, to wait for ubsequent transfer to the chuck.
  • the workpiece 118 is removed from the chuck 120 and transferred to one of the pre-chill station 136 and pit; -heat station 158, again depending on whether a sub-ambient or super-ambient i nplantation is desired.
  • the workpiece 118 is transferred to the pre-heat station 158, wherein in the present example, the workpiece is heated to a temperature greater than the dew point ter iperature of the external environment 132, as described above. Once heated c ppropriately, the workpiece 1 18 is transferred back to the load lock chamber 18.1? or transferred to the heated workpiece holding station 198.
  • the workpiece transfer arm 188 of Figs. 1 , 4, 5A-5B, and 6 is confici.ired to transfer two or more workpieces 118 concurrently between the load lock chamber 182, chuck 120, pre-chill station 136 and pre-heat station ' 58, as described above.
  • Fig. 8 illustrates an exemplary method 300 is provided for processing a workpiece at sub-ambient temperatures. It should be noted that while exemplar methods are illustrated and described herein as a series of acts or events, it will be
  • the present invention is not limited by the illustrat i.l ordering of such acts or events, as some steps may occur in different orders arid/or concurrently with other steps apart from that shown and described I erein, in accordance with the invention.
  • not all illustrated steps may be required to implement a methodology in accordance with the prese i t invention.
  • the methods may be implemen ed in association with the systems illustrated and described herein as wull as in association with other systems not illustrated.
  • the method 300 of Fig. 8 begins at act 302, wherein a first workpiece is provided in an external environment at an external temperature an:l external pressure.
  • act 304 the first workpiece is transferred from the external environment to a load lock chamber, and in act 306, the pressure v. ithin the load lock chamber is lowered to a substantial vacuum.
  • the first workpi Eice is transferred from the load lock chamber to pre-chill station within a vacuum environment of a process chamber in a cold implant ion implantatbn system in act 308, the first workpiece is cooled at the pre-chill station in act 310.
  • the first workpiece is transferred from the pre-chill station to a chuck that is cooled to the process temperature, and the workpiece is processed, such as having ions implanted therein, in act 314.
  • the first workpiece is then transferred from the chuck to a post-heat station within the vacuum environment in act 316, and the first wo Apiece is heated at the post-heat station in act 318, wherein the post-heat station is heated to a second temperature that is greater than the external- temperature.
  • Heating the workpiece in act 318 for example, comprises clamping the wc i piece to a heated workpiece support and providing a backside gas at the second
  • the first workpiece is then transferred in act 320 from the post-heat station to the load lock chamber, and the pressure within the load lock chamber is increased to the external pressure in act 322.
  • transferring the workpiece from the post-heat station to i:he load lock chamber in act 320 further comprises transferring the workpiece from the post- heat station to a heated workpiece holding station, and further tran sferring the workpiece from the heated workpiece holding station to the load look chamber.
  • the workpiece can then be removed from the load lock chamber ir act 324.
  • transferring the first workplace from the load lock chamber to the pre-chill station act 308 occurs while conoi.
  • a continuou s transfer of workpieces from the load lock chamber to the pre-chill station, to th chilled workpiece holding station, to the chuck, to the post-heat station, to ie heated workpiece holding station, and back to the load lock chamber can ij achieved by the present disclosure.
  • the workpiece transfer arm 188 can additionally transfer workpiece;; between the chilled workpiece holding station 194 and heated workpiece holdimj station 198 of Figs. 6 and 7, as described above, therein advantageously increasing throughput, while optimally providing appropriate heating and coolir g of the workpieces to prevent condensation.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Container, Conveyance, Adherence, Positioning, Of Wafer (AREA)
  • Engineering & Computer Science (AREA)
  • Robotics (AREA)
  • Physical Vapour Deposition (AREA)

Abstract

An ion implantation system provides ions to a workpiece positioned in a vacuum environment of a process chamber on a cooled chuck. A pre-chill station within the process chamber has a chilled workpiece support configured to cool the workpiece to a first temperature, and a post-heat station within the process chamber, has a heated workpiece support configured to heat the workpiece to a second temperature. The first temperature is lower than a process temperature, and the second temperature is greater than an external temperature. A workpiece transfer arm is further configured to concurrently transfer two or more workpieces between two or more of the chuck, a load lock chamber, the pre-chill station, and the post-heat station.

Description

IN-VACUUM HIGH SPEED PRE-CHILL AND POST-HEAT STATIONS
TECHNICAL FIELD
The present invention relates generally to ion implantation systems, and more specifically to preventing condensation from forming on a wor (piece in an ion implantation system.
BACKGROUND
Electrostatic clamps or chucks (ESCs) are often utilized in th≥
semiconductor industry for clamping workpieces or substrates during plasma- based or vacuum-based semiconductor processes such as ion implantation, etching, chemical vapor deposition (CVD), etc. Clamping capabilities of the ESCs, as well as workpiece temperature control, have proven to b ~.- quite valuable in processing semiconductor substrates or wafers, such ε;; silicon wafers. A typical ESC, for example, comprises a dielectric layer po sitioned over a conductive electrode, wherein the semiconductor wafer is placec Dn a surface of the ESC (e.g., the wafer is placed on a surface of the dielectric layer). During semiconductor processing (e.g., ion implantation), a clamping volta:je is typically applied between the wafer and the electrode, wherein the wafer is clamped against the chuck surface by electrostatic forces.
For certain ion implantation processes, cooling the workpieo:: via a cooling of the ESC is desirable. At colder temperatures, however, condensation can form on the workpiece, or even freezing of atmospheric water on thu surface of the workpiece can occur, when the workpiece is transferred from tho cold ESC in the process environment (e.g., a vacuum environment) to an external environment (e.g., a higher pressure, temperature, and humidity environment). For example, after an implantation of ions into the workpiece, the workpiece is typically transferred into a load lock chamber, and the load lock ch amber is subsequently is vented. When the load lock chamber is opened tc emove the workpiece therefrom, the workpiece is typically exposed to ambient atmosphere (e.g., warm, "wet" air at atmospheric pressure), wherein condensation can occur
l on the workpiece. The condensation can deposit particles on the workpiece, and/or leave residues on the workpiece that can have adverse effects on front side particles (e.g., on active areas), and can lead to defects and ptoduction losses.
· Heating of the workpiece can be performed in order to attenot to alleviate the adverse effects of condensation; however, such heating often 'soaks" the workpiece for a period of time on the ESC in order to reach a predsitermined temperature, prior to transferring the wafer. Long soak times conv<; ntiona!ly adversely affect workpiece throughput in the ion implantation system.
Therefore, a need exists in the art for an apparatus, system, and method for mitigating condensation on a workpiece while improving workpic ce throughput when transferring a cold workpiece between a "dry" or evacuated e ivironment and a "wet" or atmospheric environment. SUMMARY
The present invention overcomes the limitations of the prior ;.rt by providing a system, apparatus, and method for abating condensat ion on a workpiece and maintaining reasonable process throughput in a chil ed ion implantation system. Accordingly, the following presents a simplified summary of the disclosure in order to provide a basic understanding of some a;; pects of the invention. This summary is not an extensive overview of the inversion. It is intended to neither identify key or critical elements of the invention lor delineate the scope of the invention. Its purpose is to present some concept;; of the invention in a simplified form as a prelude to the more detailed de¾;t:ription that is presented later.
In accordance with the present disclosure, an ion implantat c n system for implanting ions into a cold workpiece is provided. The ion implantEition system, for example, comprises an ion implantation apparatus configured to provide a plurality of ions to a workpiece positioned in a process chamber, wherein the process chamber has a process environment associated therewith. In one example, a sub-ambient temperature chuck, such as a cryogenically cooled electrostatic chuck, is configured to support the workpiece within tliu process chamber during an exposure of the workpiece to the plurality of ions. The cryogenic chuck is further configured to cool the workpiece to a pr messing temperature, wherein the process temperature is below a dew poin : of an external environment.
According to one aspect, a load lock chamber is provided, wierein the load lock chamber is operably coupled to the process chamber and is configured to isolate the process environment from the external environment. The load lock chamber further comprises a workpiece support configured to support the workpiece during a transfer of the workpiece between the process chamber and the intermediate chamber.
A pre-chill station is further positioned within the process chamber, wherein the pre-chill station comprises a chilled workpiece support configured to cool the workpiece to a first temperature. In one example, the firsc temperature is significantly lower than the process temperature. The pre-chill station, for example, comprises a cooling plate configured to support the worl iece and to cool the workpiece to the first temperature. In another example, th-¾ pre-chill station further comprises a pre-chill gas sealing ring configured to iiupport a periphery of the workpiece, a pre-chill clamp configured to maintair a position of the workpiece on the chilled workpiece support, and a pre-chill ga=. source configured to provide a pre-chill gas between a gas cooling space ilefined between the workpiece and a surface of the chilled workpiece sup port. A pressure of the pre-chill gas, for example, generally determines a fooling of the workpiece.
A post-heat station is also positioned within the process chamber, wherein the post-heat station comprises a heated workpiece support config -ired to heat the workpiece to a second temperature. The post-heat station, fo- example, comprises a heating station support comprising a heating plate cci figured to support the workpiece and to heat the workpiece to the second temperature. In another example, the post-heat station further comprises a post-ht:at gas sealing ring configured to support a periphery of the workpiece, a post-heEit clamp configured to maintain a position of the workpiece on the heated workpiece support, and a post-heat gas source configured to provide a post- uat gas between a gas heating space defined between the workpiece and a surface of the heated workpiece support. Accordingly, a pressure of the posl eat gas generally determines a heating of the workpiece.
In one example, the chuck is diametrically opposed to the lo:id lock chamber within the vacuum chamber, and the pre-chill station is dii; metrically opposed to the post-heat station within the vacuum chamber.
In another exemplary aspect, the chilled workpiece holding E;tation is positioned within the process chamber, wherein the chilled workpi e holding station comprises a cold workpiece support configured to support li e workpiece when the workpiece is at the first temperature. A heated workpiecEi holding station may be further positioned within the process chamber, wheoin the heated workpiece holding station comprises a hot workpiece suppol configured to support the workpiece when the workpiece is at the second temperature. In another example, the chuck is diametrically opposed to the load lock chamber, the pre-chill station is diametrically opposed to the post-heat station, and the chilled workpiece holding station is diametrically opposed to the he;ited workpiece holding station within the vacuum chamber.
In accordance with another exemplary aspect of the disclosure, a workpiece transfer arm is configured to concurrently transfer two or more workpieces between two or more of the chuck, load lock chamber, pre-chill station, and post-heat station. The workpiece transfer arm, for example, comprises two pairs of workpiece transfer clamps positioned approximately 90 degrees from one another, wherein each pair of workpiece transfe * clamps is diametrically opposed to each other. Each pair of workpiece transfer clamps is configured to concurrently grasp or release a workpiece from the cl uck and load lock chamber, from the pre-chill station and post-heat station, and c:r the chilled workpiece holding station and heated workpiece holding station, b;3 sed on a rotational position of the workpiece transfer arm. A controller may be further configured to determine the first temperature and the second temperature, based, at least in part, on a desired process throughput. A temperature monitoring system, for example, is conf gured to measure a temperature of the workpiece at the pre-chill station and the post-heat station. The controller is thus further configured to control cooling cf the workpiece to the first temperature and the heating of the workpiece to the second temperature, based, at least in part, on the measured temperature of the workpiece.
According to another example in the disclosure, a method fo · implanting ions into a workpiece at sub-ambient temperatures is provided. A vrorkpiece is provided in an external environment at an external temperature anc external pressure and transferred from the external environment to the load lock chamber. The pressure within the load lock chamber is lowered to a substantial vacuum, and the workpiece is transferred from the load lock chamber to the Dre-chill for cooling. The pre-chill station, for example, is cooled to the first tern Derature that is lower than a process temperature, thus quickly cooling the work:>:ece. The workpiece is then transferred from the pre-chill station to the chuck that is cooled to the process temperature.
Ions are implanted into the workpiece via an ion implantation apparatus, and the workpiece is subsequently transferred from the chuck to ti n;: post-heat station within the vacuum environment. The workpiece is heated <il the post-heat station, wherein the post-heat station is heated to the second temperature that is greater than the external temperature, therein quickly heating the WDrkpiece. The workpiece is then transferred from the post-heat station to the bad lock chamber, the pressure within the load lock chamber is increased to the external pressure, and the workpiece is removed from the load lock chambi'.
In one example, the workpiece is transferred from the load ic.ck chamber to the pre-chill station occurs while concurrently transferring anothu " workpiece from the chuck to the post-heat station. Likewise, in another exarrr. le, the workpiece is transferred from the pre-chill station to the chuck occurs while concurrently transferring another workpiece from the post-heat station to the load lock chamber.
In another example, transferring the workpiece from the pre- hill station to the chuck comprises transferring the workpiece from the pre-chill st ation to the chilled workpiece holding station, and then transferring the workpiece from the chilled workpiece holding station to the chuck, while transferring the workpiece from the post-heat station to the load lock chamber comprises transferring the workpiece from the post-heat station to the heated workpiece holdirg station, and then transferring the workpiece from the heated workpiece holding station to the load lock chamber. Such transfers permit concurrent transfers of f jr workpieces via the workpiece transfer arm in a logical and through jt-sensitive manner.
The above summary is merely intended to give a brief overview of some features of some embodiments of the present invention, and other embodiments may comprise additional and/or different features than the ones mentioned above. In particular, this summary is not to be construed to be limi :i ig the scope of the present application. Thus, to the accomplishment of the fore ;oing and related ends, the invention comprises the features hereinafter described and particularly pointed out in the claims. The following description and he annexed drawings set forth in detail certain illustrative embodiments of the in. ention. These embodiments are indicative, however, of a few of the various ways in which the principles of the invention may be employed. Other objeds, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in c function with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a block diagram of an exemplary vacuum system comprising an ion implantation system in accordance with several aspects of the prssent disclosure. Fig. 2 is a cross-sectional view of an exemplary pre-chill station in accordance with another aspect of the disclosure.
Fig. 3 is a cross-sectional view of an exemplary post-heat s ; tion in accordance with yet another aspect of the disclosure.
Fig. 4 illustrates a process chamber in accordance with ano tier exemplary aspect of the disclosure.
Figs. 5A and 5B illustrate an exemplary workpiece transfer ai m in respective open and closed positions in accordance with still anotht; r aspect of the disclosure.
Fig. 6 is a schematic view of another exemplary process chamber in accordance with another aspect of the disclosure.
Fig. 7 illustrates an exemplary flow of workpieces through a chilled ion implantation system in accordance with another aspect of the disclo sure.
Fig. 8 illustrates a methodology for implanting ions into a workpiece at sub-ambient temperatures, in accordance with to still another aspect.
DETAILED DESCRIPTION
The present disclosure is directed generally toward a systei apparatus, and method for abating condensation on a workpiece and maintain ing
reasonable process throughput in a chilled ion implantation system . Accordingly, the present invention will now be described with reference to the drawings, wherein like reference numerals may be used to refer to like eleme its
throughout. It is to be understood that the description of these aspu ts are merely illustrative and that they should not be interpreted in a limitiri ;j sense. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be evident to one skilled in the art, however, that thi; present invention may be practiced without these specific details. Further, li e scope of the invention is not intended to be limited by the embodiments or examples described hereinafter with reference to the accompanying drawings, but is intended to be only limited by the appended claims and equivalents thereof. It is also noted that the drawings are provided to give an illui- tration of some aspects of embodiments of the present disclosure and therefore are to be regarded as schematic only. In particular, the elements shown in li e drawings are not necessarily to scale with each other, and the placement of various elements in the drawings is chosen to provide a clear understanding of the respective embodiment and is not to be construed as necessarily tuning a representation of the actual relative locations of the various compc r ents in implementations according to an embodiment of the invention. Fulhermore, the features of the various embodiments and examples described here may be combined with each other unless specifically noted otherwise.
It is also to be understood that in the following description, e ny direct connection or coupling between functional blocks, devices, compon 3nts, circuit elements or other physical or functional units shown in the drawings or described herein could also be implemented by an indirect connection or coupling.
Furthermore, it is to be appreciated that functional blocks or units si' own in the drawings may be implemented as separate features or circuits in one
embodiment, and may also or alternatively be fufly or partially implemented in a common feature or circuit in another embodiment. For example, several functional blocks may be implemented as software running on a common processor, such as a signal processor. It is further to be understooc that any connection which is described as being wire-based in the following specification may also be implemented as a wireless communication, unless nolcd to the contrary.
In accordance with one aspect of the present disclosure, Fig . 1 illustrates an exemplary vacuum system 100. The vacuum system 100 in the present example comprises an ion implantation system 101 , however variou 5 other types of vacuum systems are also contemplated, such as plasma proces s ng systems, or other semiconductor processing systems. The ion implantation i;/stem 101 , for example, comprises a terminal 102, a beamline assembly 104, and an end station 106. Generally speaking, an ion source 108 in the terminal 102 in coupled to a power supply 1 10 to ionize a dopant gas into a plurality of ions and to form an ion beam 112. The ion beam 112 in the present example is directed th Dugh a beam- steering apparatus 114, and out an aperture 116 towards the end :s ation 106. In the end station 106, the ion beam 1 12 bombards a workpiece 118 O.g., a semiconductor such as a silicon wafer, a display panel, etc.), which is selectively clamped or mounted to a chuck 120 (e.g., an electrostatic chuck o - ESC). Once embedded into the lattice of the workpiece 18, the implanted ions hange the physical and/or chemical properties of the workpiece. Because of this, ion implantation is used in semiconductor device fabrication and in met al finishing, as well as various applications in materials science research.
The ion beam 1 2 of the present disclosure can take any form, such as a pencil or spot beam, a ribbon beam, a scanned beam, or any other form in which ions are directed toward end station 106, and all such forms are ccintemplated as falling within the scope of the disclosure.
According to one exemplary aspect, the end station 06 comprises a process chamber 122, such as a vacuum chamber 124, wherein a process environment 126 is associated with the process chamber. The prcc ess environment 126 generally exists within the process chamber 122, .and in one example, comprises a vacuum produced by a vacuum source 28 ( ?.g., a vacuum pump) coupled to the process chamber and configured to substantially evacuate the process chamber.
During an implantation utilizing the ion implantation system 1 31 , energy can build up on the workpiece 1 18 in the form of heat, as the charged ions collide with the workpiece. Absent countermeasures, such heat can poteir ially warp or crack the workpiece 18, which may render the workpiece worthier,!; (or significantly less valuable) in some implementations. The heat can xirther cause the dose of ions delivered to the workpiece 118 to differ from the d sage desired, which can alter functionality from what is desired. Furthermore, in some circumstances, it is desirable to not only cool the workpiece 1 18 dL ring implantation to prevent heat build-up, but it may be further desirable: to implant ions at a temperature below or above an ambient temperature, sudi as to allow for desirable amorphization of the surface of the workpiece 118 enabling, among other things, ultra-shallow junction formation in advanced CMOS inlegrated circuit device manufacturing.
Thus, in accordance with another example, the chuck 120 cc mprises a sub-ambient temperature chuck 130, wherein the sub-ambient temperature chuck is configured to both support and cool or otherwise maintain ;a
predetermined temperature on the workpiece 118 within the process chamber 122 during the exposure of the workpiece to the ion beam 112. It :s iould be noted that while the chuck 20 is referred to in the present example! as being the sub-ambient temperature chuck 130, the chuck 120 can likewise comprise a super-ambient temperature chuck (not shown), wherein the super-?; mbient temperature chuck is configured to support and heat the workpiec 1 18 within the process chamber 122.
The sub-ambient temperature, chuck 130, for example, is an electrostatic chuck configured to cool or chill the workpiece 118 to a processinci :emperature that is considerably lower than an ambient or atmospheric tempers lure of the surroundings or external environment 132 {e.g., also called an "atmospheric environment"). Likewise, in a case where the chuck 120 comprises; the above- described super-ambient temperature chuck, the super-ambient temperature chuck may comprise an electrostatic chuck configured to heat the workpiece 8 to a processing temperature that is considerably higher than the an bient or atmospheric temperature of the surroundings or external environmc nt 132. A cooling system 134 may be further provided, wherein, in another example, the cooling system is configured to cool or chill the sub-ambient temperature chuck 130, and thus, the workpiece 118 residing thereon, to the processing
temperature. In another example, and in a similar manner, a heatir g system (not shown) may be further provided in the case of a super-ambient temperature chuck, wherein the heating system is configured to heat the super- ;;imbient temperature chuck and workpiece 118 residing thereon to the proc ssing temperature. In some exemplary operations of the vacuum system 100, l e processing temperature is be!ow the ambient dew point (e.g., 8 degrees C, al:» called dew point temperature) of the external environment 132, such as a processing temperature of approximately -40 degrees C. In such an operation since the processing temperature is significantly lower than the dew point tenperature of the external environment 32, without warming of the workpiece 1 18 prior to exposure to the external environment, condensation may form ther son, thus potentially deleteriously affecting the workpiece, as will be discusse d in greater detail hereafter.
However, the inventors appreciate that cooling of the workplace 118 can deleteriously affect cycle time through the vacuum system 100, wherein conventionally, the workpiece is allowed to "soak" on the chuck 1 0 until the desired temperature is reached. In order to increase process throi.ghput, the present disclosure thus provides a pre-chill station 36 positioned within the vacuum environment 126 of the process chamber 120. The pre-chill station 136, for example, comprises a chilled workpiece support 138, as illustr ted further in Fig. 2, wherein the chilled workpiece support 38 is configured to cool the workpiece to a first temperature.
The chilled workpiece support 138, for example, comprises ;3 thermal pad 140, such as a cooling plate 142, wherein the thermal pad is configured to support the workpiece and to cool the workpiece to the first tempe rature. The thermal pad 140, for example, comprises a cooling plate 142 comprising one or . more of a peltier cooler, an expansion chamber, a cryogenic head, and a circulatory refrigeration loop.
In another exemplary aspect, the pre-chill station 136 of Fiy 1 further comprises a pre-chill gas sealing ring 144, as illustrated again in Fig. 2, wherein the pre-chill gas sealing ring is generally disposed about a perimeter of the chilled workpiece support 138. The pre-chill gas sealing ring 144, or example, is configured to support a periphery 146 of the workpiece 118, and t:i generally provide a seal between the workpiece and the chilled workpiece si. pport 138. According to another example, a pre-chill clamp 148 is further provided, wherein the pre-chill clamp is configured to maintain a position of the workp ece 1 18 on the chilled workpiece support 138. As illustrated again in Fig. 1 , a f>re-chill gas source 150 is further provided, wherein the pre-chill gas source is configured to provide a pre-chill gas 152 between a gas cooling space 154 illustrated in Fig. 2, wherein the gas cooling space is defined between the workpiece 1 ' 8 and a surface 156 of the chilled workpiece support 138. As such, a pres ure of the pre- chill gas 152 within the gas cooling space 154 is configured to generally determine a cooling of the workpiece 1 18.
The rate of heat transfer between the workpiece 118 and tri<; chilled workpiece support 138 is generally proportional to the temperature difference between the workpiece and the chilled workpiece support. In gems al,
T(t) = T∞ + (To - e W (1) where T(t) is the temperature of the workpiece 18 being cooled or heated as a function of time, T∞ is the temperature of object doing the cooling oi heating, which in this case, sit he chilled workpiece support 138, T0 is the inkial temperature of the workpiece, e is the Euler number (2.71828...), t is time, and τ a time constant which depends, among other factors, on the heat transfer coefficient. As will be understood from equation (1 ), it is substantia ly quicker to get the workpiece 118 to a predetermined temperature when the t, nperature of the chilled workpiece support 138 is overdriven to a first temperature that is lower than the processing temperature. In one example, the first tempera ture is at least an order of magnitude lower than the process temperature, lor example, if a process temperature of -40C is desired, it would take many time tOnstants to be acceptably close to -40C if the chilled workpiece support 138 we re held at - 40C. However, if the chilled workpiece support 138 is driven to a first
temperature of -100C, for example, the desired process temperatu e of -40C could be achieved in just over half a time constant. As such, the ch'lled workpiece support 138 is configured to cool at the first temperature wherein the first temperature is significantly lower than the desired processing temperature.
In still another exemplary aspect, the post-heat station 58 c:f Fig. 1 is further positioned within the vacuum environment 126 of the proce s chamber 122, wherein the post-heat station further comprises a heated workpiece support 160, as illustrated in Fig. 3, configured to heat the workpiece 118 to a second temperature. The heated workpiece support 160, for example, com arises another thermal pad 140, such as a heating plate 161 , wherein the thermal pad is configured to support the workpiece and to heat the workpiece to tin. second temperature. The post-heat station 158 for example, further comprises a post- heat gas sealing ring 162, wherein the post-heat gas sealing ring is. generally disposed about a perimeter 164 of the heated workpiece support 1 :>D. The post- heat gas sealing ring 162, for example, is configured to support the jeriphery 146 of the workpiece 118, and to generally provide a seal between the w orkpiece and the heated workpiece support 160.
According to another example, a post-heat damp 166 is further provided, wherein the post-heat clamp is configured to maintain a position of ie workpiece 118 on the heated workpiece support 160. As illustrated again in F ig. 1 , a post- heat gas source 168 is further provided, wherein the post-heat gas i;ource is configured to provide a post-heat gas 170 between a gas heating∑|: ace 172 illustrated in Fig. 3, wherein the gas heating space is defined between the workpiece 118 and a surface 174 of the heated workpiece support 138. As such, a pressure of the post-heat gas 170 within the gas heating space 172 is configured to generally determine a heating of the workpiece 118.
Similar to the cooling described above, heating of the workpiece 118 in the post-heat station 158 of Fig. 1 can be overdriven, wherein the seccr d
temperature is significantly greater than the processing temperatut E!. As such, a time needed to heat the workpiece back to the external temperature of the external environment 132 can be significantly reduced by the present disclosure. In one exemplary aspect of the disclosure, the post-heat station 15.! and pre-chill station 136 are generally isolated from one another within the proos >s chamber 122, wherein heat transfer between the post-heat station and pre-cNII station is minimized. In one example, the second temperature is no greater than 100C to approximately 150C, wherein stability of a conventional photoresisi: Degins to decay. In accordance with another example, a temperature monitor ng system 176 is further provided, and configured to measure a temperature <:f the workpiece 118 at the pre-chill station 136 and the post-heat station 158, as illustrated in Fig. 4. The temperature monitoring system 176, for e :> ample, comprises one or more workpiece temperature monitoring devices: 78A, 178B configured to measure a temperature of the workpiece 1 18 residing on the respective pre-chill station 136 and the post-heat station 58, thus nonitoring the temperature of the workpiece during cooling and heating thereof, a id improving process efficiencies. A controller 180 illustrated in Fig. 1 , for example, is further configured to control cooling of the workpiece 1 18 to the first temp* rature and the heating of the workpiece to the second temperature, based, at least in part, on the measured temperature of the workpiece.
In accordance with another aspect, referring again to Fig. 1 , a load lock chamber 182 is further operably coupled to the process chamber \: 2, wherein the load lock chamber is configured to isolate the process environment 126 from the external environment 132. The load lock chamber 182 further comprises a workpiece support 184 configured to support the workpiece 118 du 'ing a transfer of the workpiece between the process chamber 122 and the extern al
environment 132. A plurality of load lock doors 186A, 186B operably couple the load lock chamber 182 to the respective process chamber 122 and the external environment 132.
In accordance with still another aspect of the disclosure, a workpiece transfer arm 188 is provided, wherein the workpiece transfer arm i=; configured to concurrently transfer two or more workpieces 1 8 between two or nore of the chuck 120, load lock chamber 182, pre-chill station 136, and post-heat station 158. One or more auxiliary transfer arms 189 may be further provided to assist in transferring workpieces, in accordance with another example. The workpiece transfer arm 188, as illustrated in greater detail in Fig. 4, comprise.: two pairs 190A, 190B of workpiece transfer clamps 192A, 192B positioned approximately 90 degrees from one another, wherein each pair of workpiece transfer clamps is diametrically opposed to each other. Each pair 190A, 190B of wci piece transfer clamps 192A, 192B is configured to concurrently grasp or release a workpiece 118 from the chuck 120 and load lock chamber 182, or Inm the pre- chill station 136 and post-heat station 158, based on a rotational position of the workpiece transfer arm 88.
The workpiece transfer arm 188, for example, has the ability to rotate
(e.g., Θ) as well as to move in and out (e.g., in the z-direction). T workpiece transfer arm 188, for example, is part of an assembly (not shown) o>mprised of two arms that rotate together and can be opened and close like sc !i sors, in order to effectuate gripping and releasing workpieces 118. For example, Fig. 5A illustrates the two pairs 190A, 190B of workpiece transfer clamps ' !)2A, 192B in an open position 193A, wherein the workpiece transfer clamps are operable to generally surround, but not contact the two or more workpieces 11 i: . In the example of Fig. 5B, the workpiece transfer clamps 192A, 192B are in a closed position 193B, wherein the workpiece transfer clamps are position id to contact and concurrently grip the two or more workpieces 18.
According to still another aspect, as illustrated schematicall in Fig. 6, a chilled workpiece holding station 194 is positioned within the process chamber 122, wherein the chilled workpiece holding station comprises a co t: workpiece support 196 configured to support the workpiece 1 18 once the wc piece is at the first temperature in the pre-chill station 136. The cold workpie:;3 support 196, for example, is further configured to maintain the temperature of thi¾ workpiece 1 18 while the workpiece resides on the cold workpiece support 1 S<: . A heated workpiece holding station 198 is further positioned within the proc ss chamber 122, wherein the heated workpiece holding station comprises a hoi workpiece support 199 configured to support the workpiece 8 when the woikpiece is at the second temperature. The hot workpiece support 199, for exair pie, is further configured to maintain the temperature of the workpiece 118 whilii the workpiece resides on the hot workpiece support 199.
As illustrated in the example of Fig. 6, the chuck 120 is diametrically opposed to the load lock chamber 182, the pre-chill station 136 is diametrically opposed to the post-heat station 158, and the chilled workpiece holding station 194 is diametrically opposed to the heated workpiece holding station 198 within the process chamber 122. It should be noted that various other configurations and locations of the chuck 120, load lock chamber 182, pre-chill sta tion 136, post-heat station 158, chilled workpiece holding station 194, and h eated workpiece holding station 198 within the process chamber 122 are; contemplated as falling within the scope of the present disclosure. For example: :he chilled workpiece holding station 194 may be positioned opposite the pre -chill station 136, and the heated workpiece holding station 198 may be positioned opposite the post-heat station 158. Such a configuration may provide an advantageous flow of workpieces 1 18, depending on the configuration of the wor kpiece transfer arm 188. Further, for simplicity, the load lock chamber 182 is illustrated as being within the process chamber 122; however, it should be understood that the load lock door 186A of Fig. 4 operably couples the load lock chamber 1 ii2 to process chamber.
An exemplary flow scheme or transference of workpieces 1 18 in association with the vacuum system 100 of Fig. 1 will now be briellv discussed in order to provide one of many operational examples of an operatio n of the vacuum system. It should be noted that the present disclosure is riot limited to the exemplary flow provided, and that various other transferences of workpieces 1 18 into, out of, and within the vacuum system 100 are contemplated as falling within the scope of the present disclosure.
In one exemplary workpiece flow 200, as illustrated in Fig. 7 the workpiece 18 of Fig. 6, for example, is transferred out of the load ock chamber 182 to one of the pre-chill station 136 and pre-heat station 158 within the process chamber 122, depending on whether a sub-ambient or super-ambient implantation is desired. For example, in a sub-ambient implantatio i (e.g., an implantation at a temperature below ambient temperature), the workpiece 1 18 is transferred to the pre-chill station 136, wherein the workpiece is pro-chilled to approximately the processing temperature. Once cooled via the p-i s-chill station 136 (or heated via the pre-heat station 158) to approximately the processing temperature, the workpiece 1 18 is either transferred to the chuck 1 20 for appropriate implantation of ions according to process requirements., or transferred to the chilled workpiece holding station 194, to wait for ubsequent transfer to the chuck.
Once the implantation is complete, the workpiece 118 is removed from the chuck 120 and transferred to one of the pre-chill station 136 and pit; -heat station 158, again depending on whether a sub-ambient or super-ambient i nplantation is desired. In the above sub-ambient implantation example, the workpiece 118 is transferred to the pre-heat station 158, wherein in the present example, the workpiece is heated to a temperature greater than the dew point ter iperature of the external environment 132, as described above. Once heated c ppropriately, the workpiece 1 18 is transferred back to the load lock chamber 18.1? or transferred to the heated workpiece holding station 198. It should bs noted that the workpiece transfer arm 188 of Figs. 1 , 4, 5A-5B, and 6 is confici.ired to transfer two or more workpieces 118 concurrently between the load lock chamber 182, chuck 120, pre-chill station 136 and pre-heat station ' 58, as described above.
In accordance with another exemplary aspect of the invention, Fig. 8 illustrates an exemplary method 300 is provided for processing a workpiece at sub-ambient temperatures. It should be noted that while exemplar methods are illustrated and described herein as a series of acts or events, it will be
appreciated that the present invention is not limited by the illustrat i.l ordering of such acts or events, as some steps may occur in different orders arid/or concurrently with other steps apart from that shown and described I erein, in accordance with the invention. In addition, not all illustrated steps may be required to implement a methodology in accordance with the prese i t invention. Moreover, it will be appreciated that the methods may be implemen ed in association with the systems illustrated and described herein as wull as in association with other systems not illustrated.
The method 300 of Fig. 8 begins at act 302, wherein a first workpiece is provided in an external environment at an external temperature an:l external pressure. In act 304, the first workpiece is transferred from the external environment to a load lock chamber, and in act 306, the pressure v. ithin the load lock chamber is lowered to a substantial vacuum. The first workpi Eice is transferred from the load lock chamber to pre-chill station within a vacuum environment of a process chamber in a cold implant ion implantatbn system in act 308, the first workpiece is cooled at the pre-chill station in act 310. The pre- chill station, for example, is cooled to a first temperature that is lov/ijr than a process temperature. Cooling of the workpiece in act 310, for exanple, comprises clamping the workpiece to a chilled workpiece support =nd providing a backside gas at the first temperature to a backside of the workpieosj.
In act 312, the first workpiece is transferred from the pre-chill station to a chuck that is cooled to the process temperature, and the workpiece is processed, such as having ions implanted therein, in act 314. In accordance ith one example, transferring the workpiece from the pre-chill station to th=: chuck in act 312 further comprises transferring the workpiece from the pre-chill station to a chilled workpiece holding station, and further transferring the work|: iece from the chilled workpiece holding station to the chuck.
The first workpiece is then transferred from the chuck to a post-heat station within the vacuum environment in act 316, and the first wo Apiece is heated at the post-heat station in act 318, wherein the post-heat station is heated to a second temperature that is greater than the external- temperature. Heating the workpiece in act 318, for example, comprises clamping the wc i piece to a heated workpiece support and providing a backside gas at the second
temperature to a backside of the workpiece.
The first workpiece is then transferred in act 320 from the post-heat station to the load lock chamber, and the pressure within the load lock chamber is increased to the external pressure in act 322. In accordance wit one other example, transferring the workpiece from the post-heat station to i:he load lock chamber in act 320 further comprises transferring the workpiece from the post- heat station to a heated workpiece holding station, and further tran sferring the workpiece from the heated workpiece holding station to the load look chamber. The workpiece can then be removed from the load lock chamber ir act 324. In accordance with one example, transferring the first workplace from the load lock chamber to the pre-chill station act 308 occurs while conoi. rrently transferring a second workpiece from the chuck to the post-heat st;a ion in act 318. Likewise, transferring the workpiece from the pre-chill station 1:D the chuck in act 312 occurs while concurrently transferring a third workpiece IV Dm the post- heat station to the load lock chamber, and so on. Thus, a continuou s transfer of workpieces from the load lock chamber to the pre-chill station, to th chilled workpiece holding station, to the chuck, to the post-heat station, to ie heated workpiece holding station, and back to the load lock chamber can ij achieved by the present disclosure. Further, the workpiece transfer arm 188 of Figs. 1 , 4, 5A- 5B, and 6 can advantageously transfer two or more workpieces 1 1 Ei concurrently between the load lock chamber 182, chuck 120, pre-chill station and preheat station 158, as illustrated in Figs. 4, 5A, and 5B. In an additior al example, the workpiece transfer arm 188 can additionally transfer workpiece;; between the chilled workpiece holding station 194 and heated workpiece holdimj station 198 of Figs. 6 and 7, as described above, therein advantageously increasing throughput, while optimally providing appropriate heating and coolir g of the workpieces to prevent condensation.
Although the invention has been shown and described with r aspect to a certain embodiment or embodiments, it should be noted that the al: Dve-described embodiments serve only as examples for implementations of some embodiments of the present invention, and the application of the present invention is not restricted to these embodiments. In particular regard to the various; functions performed by the above described components (assemblies, devices, circuits, etc.), the terms (including a reference to a "means") used to describ e such components are intended to correspond, unless otherwise indicate;-:!, to any component which performs the specified function of the described component (i.e., that is functionally equivalent), even though not structurally e jivalent to the disclosed structure which performs the function in the herein illustra ted
exemplary embodiments of the invention. In addition, while a part cular feature of the invention may have been disclosed with respect to only one of several embodiments, such feature may be combined with one or more ot Ί sr features of the other embodiments as may be desired and advantageous for a y given or particular application. Accordingly, the present invention is not to be limited to the above-described embodiments, but is intended to be limited only by the appended claims and equivalents thereof.

Claims

CLAIMS In the Claims:
1. An ion implantation system, comprising:
a vacuum chamber having a process environment associated therewith;
an ion implantation apparatus configured to provide a plurality of ions to a workpiece positioned in the vacuum chamber;
a chuck configured to support the workpiece within the vacuum cha mber during an exposure of the workpiece to the plurality of ions, wherein the chuck \u configured to cool the workpiece to a processing temperature;
a load lock chamber operably coupled to the vacuum chamber, whurein the load lock chamber is configured to isolate the process environment from an e lernal environment, and wherein the load lock chamber comprises a workpiece support configured to support the workpiece during a transfer of the workpiece between the process chamber and external environment; and
a pre-chill station positioned within the process chamber, wherein 1 ie pre-chill station comprises a chilled workpiece support configured to cool the workpiece to a first temperature;
a post-heat station positioned within the process chamber, wherei the post-heat station comprises a heated workpiece support configured to heat the WOJ I· piece to a second temperature; and
a workpiece transfer arm, wherein the workpiece transfer arm is configured to concurrently transfer two or more workpieces between two or more of the chuck, load lock chamber, pre-chill station, and post-heat station.
2. The ion implantation system of claim 1 , wherein the chuck comprises an electrostatic chuck configured to cool the workpiece to the processing ten perature.
3. The ion implantation system of claim 1 , wherein the workpiese transfer arm comprises two pairs of workpiece transfer clamps positioned approximately 90 degrees from one another, wherein each pair of workpiece transfer clam :>s is diametrically opposed to each other, and wherein each pair of workpiece Iransfer clamps is configured to concurrently grasp or release a workpiece from tlvj chuck and load lock chamber, or from the pre-chill station and post-heat station, ba d on a rotational position of the workpiece transfer arm.
4. The ion implantation system of claim 1 , wherein the first tenoerature is lower than the process temperature.
5. The ion implantation system of claim 1 , wherein the pre-chil! station comprises a cooling plate configured to support the workpiece and to cool the workpiece to the first temperature.
6. The ion implantation system of claim 5, wherein the coolinc Dlate comprises one or more of a pettier cooler, an expansion chamber, a cryo enic head, and a circulatory refrigeration loop.
7. The ion implantation system of claim 5, wherein the pre-chill station further comprises:
a pre-chill gas sealing ring disposed about a perimeter of the chilled workpiece support, wherein the pre-chill gas sealing ring is configured to support a sriphery of the workpiece;
a pre-chill clamp configured to maintain a position of the workpiecs: on the chilled workpiece support; and
a pre-chill gas source configured to provide a pre-chill gas betwee i a gas cooling space defined between the workpiece and a surface of the chilled workp c ce support, wherein a pressure of the pre-chill gas generally determines a cooling of t:ne workpiece.
8. The ion implantation system of claim 1 , wherein the post-hi2.at station comprises a heating station support comprising a heating plate configure d to support the workpiece and to heat the workpiece to the second temperature.
9. The ion implantation system of claim 8, wherein the post-he ;:t station further comprises:
a post-heat gas sealing ring disposed about a perimeter of the he£ii:3d workpiece support, wherein the post-heat gas sealing ring is configured to support a Deriphery of the workpiece;
a post-heat clamp configured to maintain a position of the workpie :^ on the heated workpiece support; and
a post-heat gas source configured to provide a post-heat gas between a gas heating space defined between the workpiece and a surface of the heatec; workpiece support, wherein a pressure of the post-heat gas generally determines a 1' eating of the workpiece.
10. The ion implantation system of claim 1 , further comprising:
a chilled workpiece holding station positioned within the process chamber, wherein the chilled workpiece holding station comprises a cold workpiece support configured to support the workpiece when the workpiece is at the first temperature; a heated workpiece holding station positioned within the process chamber, wherein the heated workpiece holding station comprises a hot workpiece support configured to support the workpiece when the workpiece is at the second temperature.
11. The ion implantation system of claim 10, wherein the chuck s
diametrically opposed to the load lock chamber, the pre-chill station is di:a metrically opposed to the post-heat station, and the chilled workpiece holding station is diametrically opposed to the heated workpiece holding station within the \acuum chamber.
12. The ion implantation system of claim 1 1 , wherein the workpiece transfer arm comprises two pairs of workpiece transfer clamps positioned approximately 90 degrees from one another, wherein each pair of workpiece transfer clampis is diametrically opposed to each other, and wherein each pair of workpiece xansfer clamps is configured to concurrently grasp or release a workpiece from the chuck and load lock chamber, the from the pre-chill station and post-heat station, or 1 ie chilled workpiece holding station and heated workpiece holding station, based on a rotational position of the workpiece transfer arm.
13. The ion implantation system of claim 1 , wherein the chuck i:; diametrically opposed to the load lock chamber, and the pre-chill station is diametricall ' opposed to the post-heat station within the vacuum chamber.
14. The ion implantation system of claim 1 , wherein the workpiec e transfer arm comprises a pair of workpiece transfer clamps that are diametrically opposed to each other, and wherein the pair of workpiece transfer clamps are configu. ed to concurrently grasp or release a workpiece from the chuck and load lock chamber, or from the pre-chill station and post-heat station, based on a rotational posi J :>n of the workpiece transfer arm.
15. The ion implantation system of claim 1 , wherein the post-he^t station and pre-chill station are generally isolated from one another within the proces;; chamber.
16. The ion implantation system of claim 1 , further comprising a controller configured to determine the first temperature and the second temperature, based, at least in part, on a desired process throughput.
17. The ion implantation system of claim 16, further comprising =i temperature monitoring system configured to measure a temperature of the workpiece ;it the pre-chill station and the post-heat station, wherein the controller is further configure j to control cooling of the workpiece to the first temperature and the heating of the workpiece to the second temperature, based, at least in part, on the measured temperature; of the workpiece.
18. A method for implanting ions into a workpiece at sub-ambie nt temperatures, the method comprising:
providing a workpiece in an external environment at an external ten perature and external pressure;
transferring the workpiece from the external environment to a load luck chamber; lowering the pressure within the load lock chamber to a substantial vacuum; transferring the workpiece from the load lock chamber to pre-chili st ation within a vacuum environment of a process chamber in a cold implant ion implanta n Dn system; cooling the workpiece at the pre-chill station, wherein the pre-chill Nation is cooled to a first temperature that is lower than a process temperature;
transferring the workpiece from the pre-chill station to a chuck that i:; cooled to the process temperature;
implanting ions into the workpiece;
transferring the workpiece from the chuck to a post-heat station witVm the vacuum environment;
heating the workpiece at the post-heat station, wherein the post-he.it station is heated to a second temperature that is greater than the external temperat.ire;
transferring the workpiece from the post-heat station to the load lock chamber; increasing the pressure within the load lock chamber to the external pressure; and
removing the workpiece from the load lock chamber.
19. The method of claim 18, wherein cooling the workpiece comp-ises clamping the workpiece to a chilled workpiece support and providing a bad :side gas at the first temperature to a backside of the workpiece.
20. The method of claim 8, wherein heating the workpiece comprises clamping the workpiece to a heated workpiece support and providing a ai: (side gas at the second temperature to a backside of the workpiece.
21. The method of claim 18, wherein the first temperature is at l ast an order of magnitude lower than the process temperature and the second temper itu re is not more than approximately 150C.
22. The method of claim 18, wherein transferring the workpiece: From the load lock chamber to the pre-chill station occurs while concurrently transferrin :! another workpiece from the chuck to the post-heat station.
23. The method of claim 22, wherein transferring the workpiec from the pre- chill station to the chuck occurs while concurrently transferring the anothia - workpiece from the post-heat station to the load lock chamber.
24. The method of claim 18, wherein transferring the workpiect; from the pre- chill station to the chuck comprises:
transfenring the workpiece from the pre-chill station to a chilled wor cpiece holding station; and
transferring the workpiece from the chilled workpiece holding statbn to the chuck.
25. The method of claim 18, wherein transferring the workpiece from the post- heat station to the load lock chamber comprises:
transferring the workpiece from the post-heat station to a heated u rkpiece holding station; and
transferring the workpiece from the heated workpiece holding station to the load lock chamber.
26. The method of claim 18, wherein transferring the workpiece comprises concurrently transferring two or more workpieces.
PCT/US2013/053567 2012-08-03 2013-10-02 In-vacuum high speed pre-chill and post-heat stations Ceased WO2014022844A2 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
KR1020157005135A KR102126367B1 (en) 2012-08-03 2013-10-02 In-vacuum high speed pre-chill and post-heat stations
JP2015525641A JP6267201B2 (en) 2013-10-02 2013-10-02 Fast pre-cooling and post-heating station under vacuum
CN201380041167.6A CN104685604B (en) 2013-10-02 2013-10-02 High speed in vacuum pre-chill station and rear heat stations

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US13/566,013 2012-08-03
US13/566,013 US9236216B2 (en) 2012-08-03 2012-08-03 In-vacuum high speed pre-chill and post-heat stations

Publications (2)

Publication Number Publication Date
WO2014022844A2 true WO2014022844A2 (en) 2014-02-06
WO2014022844A3 WO2014022844A3 (en) 2014-03-27

Family

ID=49585569

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2013/053567 Ceased WO2014022844A2 (en) 2012-08-03 2013-10-02 In-vacuum high speed pre-chill and post-heat stations

Country Status (3)

Country Link
US (1) US9236216B2 (en)
KR (1) KR102126367B1 (en)
WO (1) WO2014022844A2 (en)

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080138178A1 (en) * 2006-12-06 2008-06-12 Axcelis Technologies,Inc. High throughput serial wafer handling end station
US9663854B2 (en) * 2013-03-14 2017-05-30 Taiwan Semiconductor Manufacturing Company, Ltd. High-throughput system and method for post-implantation single wafer warm-up
JP6151080B2 (en) * 2013-04-26 2017-06-21 株式会社ニューフレアテクノロジー Charged particle beam lithography system
US9378992B2 (en) * 2014-06-27 2016-06-28 Axcelis Technologies, Inc. High throughput heated ion implantation system and method
US20160203950A1 (en) * 2015-01-13 2016-07-14 Advanced Ion Beam Technology, Inc. Method and ion implanter for low temperature implantation
US9607803B2 (en) * 2015-08-04 2017-03-28 Axcelis Technologies, Inc. High throughput cooled ion implantation system and method
CN109417010B (en) * 2016-06-02 2021-04-13 艾克塞利斯科技公司 Apparatus and method for heating or cooling wafers
US10128084B1 (en) * 2017-09-18 2018-11-13 Axcelis Technologies, Inc. Wafer temperature control with consideration to beam power input
US10227693B1 (en) 2018-01-31 2019-03-12 Axcelis Technologies, Inc. Outgassing impact on process chamber reduction via chamber pump and purge
JP7130127B2 (en) * 2018-11-06 2022-09-02 エーエスエムエル ネザーランズ ビー．ブイ． Systems and methods for thermal conditioning of wafers in charged particle beam devices
US11901198B2 (en) 2019-07-12 2024-02-13 Axcelis Technologies, Inc. Toxic outgas control post process
US12563997B2 (en) * 2020-07-21 2026-02-24 Taiwan Semiconductor Manufacturing Co., Ltd. Warm wafer after ion cryo-implantation
JP2022165477A (en) * 2021-04-20 2022-11-01 日新イオン機器株式会社 Wafer support device
CN117941024A (en) 2021-08-05 2024-04-26 艾克塞利斯科技公司 Hybrid energy ion implantation
CN113972154B (en) * 2021-10-20 2026-04-21 北京北方华创微电子装备有限公司 Process chambers, semiconductor process equipment and semiconductor process methods
CN115101399B (en) * 2022-06-28 2025-06-17 上海集成电路研发中心有限公司 Low temperature ion implantation method and device

Family Cites Families (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0614516B2 (en) * 1991-04-18 1994-02-23 東京エレクトロン株式会社 Wafer vacuum processing equipment
DE69316872T2 (en) * 1992-11-06 1998-05-28 Varian Associates ELECTROSTATIC CLAMPING DEVICE FOR HOLDING A WAFER
US5828070A (en) 1996-02-16 1998-10-27 Eaton Corporation System and method for cooling workpieces processed by an ion implantation system
US6167274A (en) * 1997-06-03 2000-12-26 At&T Wireless Svcs. Inc. Method for locating a mobile station
JP2000003879A (en) * 1998-06-12 2000-01-07 Sony Corp Substrate cooling mechanism
US6158951A (en) * 1998-07-10 2000-12-12 Asm America, Inc. Wafer carrier and method for handling of wafers with minimal contact
US6322312B1 (en) * 1999-03-18 2001-11-27 Applied Materials, Inc. Mechanical gripper for wafer handling robots
JP2003022962A (en) * 2001-07-10 2003-01-24 Canon Inc Exposure system, device manufacturing method, semiconductor manufacturing factory, and maintenance method for exposure apparatus
US6597964B1 (en) * 2002-05-08 2003-07-22 Taiwan Semiconductor Manufacturing Co., Ltd Thermocoupled lift pin system for etching chamber
US7458763B2 (en) * 2003-11-10 2008-12-02 Blueshift Technologies, Inc. Mid-entry load lock for semiconductor handling system
US7344352B2 (en) * 2005-09-02 2008-03-18 Axcelis Technologies, Inc. Workpiece transfer device
US7655933B2 (en) * 2006-08-15 2010-02-02 Varian Semiconductor Equipment Associates, Inc. Techniques for temperature-controlled ion implantation
US7935942B2 (en) * 2006-08-15 2011-05-03 Varian Semiconductor Equipment Associates, Inc. Technique for low-temperature ion implantation
WO2008039943A2 (en) * 2006-09-27 2008-04-03 Vserv Tech Wafer processing system with dual wafer robots capable of asynchronous motion
US7960297B1 (en) * 2006-12-07 2011-06-14 Novellus Systems, Inc. Load lock design for rapid wafer heating
US7789443B2 (en) * 2007-03-16 2010-09-07 Axcelis Technologies, Inc. Workpiece gripping device
US8328494B2 (en) * 2009-12-15 2012-12-11 Varian Semiconductor Equipment Associates, Inc. In vacuum optical wafer heater for cryogenic processing
JP5635378B2 (en) * 2010-11-30 2014-12-03 日東電工株式会社 Semiconductor wafer transfer method and semiconductor wafer transfer apparatus

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None

Also Published As

Publication number Publication date
KR102126367B1 (en) 2020-06-24
WO2014022844A3 (en) 2014-03-27
US9236216B2 (en) 2016-01-12
KR20150067134A (en) 2015-06-17
US20140034846A1 (en) 2014-02-06

Similar Documents

Publication Publication Date Title
US9236216B2 (en) In-vacuum high speed pre-chill and post-heat stations
US9711324B2 (en) Inert atmospheric pressure pre-chill and post-heat
KR100692496B1 (en) Heat treatment method and apparatus for semiconductor substrate
KR101817185B1 (en) Active dew point sensing and load lock venting to prevent condensation of workpieces
CN104685604B (en) High speed in vacuum pre-chill station and rear heat stations
US20080042078A1 (en) Techniques for temperature-controlled ion implantation
WO2012064371A1 (en) Post implant wafer heating using light
CN107851546B (en) High-throughput cooled ion implantation system and method
KR20030096732A (en) Cooling stage of CVD apparatus for manufacturing semiconductor device
KR102470334B1 (en) Radiant heating pre-soak
TWI910264B (en) Hybrid high-temperature electrostatic clamp for improved workpiece temperature uniformity
US20250183085A1 (en) Large range heated electrostatic chuck
JP7440414B2 (en) Impact of outgassing on process chamber reduction with chamber pumps and purges
TWI633570B (en) Ion implantation system and method for implanting ions into a workpiece

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 13792115

Country of ref document: EP

Kind code of ref document: A2

ENP Entry into the national phase

Ref document number: 2015525641

Country of ref document: JP

Kind code of ref document: A

ENP Entry into the national phase

Ref document number: 20157005135

Country of ref document: KR

Kind code of ref document: A

122 Ep: pct application non-entry in european phase

Ref document number: 13792115

Country of ref document: EP

Kind code of ref document: A2