Vaporizer

Abstract

Vapor delivery systems and methods that control the heating and flow of vapors from solid feed material, especially material that comprises cluster molecules for semiconductor manufacture. The systems and methods safely and effectively conduct the vapor to a point of utilization, especially to an ion source for ion implantation. Ion beam implantation is shown employing ions from the cluster materials. The vapor delivery system includes reactive gas cleaning of the ion source, control systems and protocols, wide dynamic range flow-control systems and vaporizer selections that are efficient and safe. Borane, decarborane, carboranes, carbon clusters and other large molecules are vaporized for ion implantation. Such systems are shown cooperating with novel vaporizers, ion sources, and reactive cleaning systems.

1 . A flow interface device in the form of a thermally conductive valve block which defines at least one vapor passage, the passage associated with at least first and second vapor transfer interfaces, one interface comprising a vapor inlet located to receive vapor from a vaporizer of solid feed material and communicating with an inlet portion of the passage, and the other interface comprising a vapor outlet for delivery of vapor from an outlet portion of the passage to a vapor-receiving device, the valve block having at least one vapor valve and constructed to heat the passage and deliver vapor from the vaporizer to the vapor receiving device. 
     
     
         2 - 57 . (canceled) 
     
     
         58 . In a vaporizer unit having a heater and constructed to contain and heat a solid feed material to a temperature that produces vapor to be ionized, the vaporizer unit constructed to hang vertically and comprising a canister body having a solids-receiving volume and a detachable top closure member, the top closure member defining a mounting surface for the canister at a mounting station and a valve permitting vapor flow from the canister to the mounting station,
 the improvement wherein the heater for vaporizing solid material in the body of the canister is located in the detachable top closure member, and serves to maintain the valve of the top closure member at temperature higher than the temperature to which the solid material is heated.   
     
     
         59 . The vaporizer unit of  claim 58  in which the valve is comprised of thermally conductive aluminum and is disposed in conductive heat transfer relationship with the heater to maintain the vapor passage through the valve at higher temperature than that of the solid material being vaporized. 
     
     
         60 . The vaporizer until of  claim 58  having a single heating zone comprising one or more heating elements mounted by the top closure member. 
     
     
         61 . The vaporizer of  claim 59  in which the heater comprises cartridge heaters within receptacle in the top closure member. 
     
     
         62 . The vaporizer of  claim 58  including a detachable fastening for mounting the vaporizer at a mounting station and a hand-operable closing device, the closing device having a closed position preventing vapor flow from the vaporizer, the closing device associated with an access-preventing device that prevents access of workers to the detachable fastening of a mounted vaporizer except when the closing device is in closed position, thereby to prevent flow of toxic vapor from the vaporizer while the vaporizer is being detached. 
     
     
         63 . The vaporizer of  claim 62  in which the detachable fasteners comprise a pattern of holding screws or nuts engageable with mating fittings associated with the mounting station, and the access-preventing device comprises an access-preventing shield that moves dependently with a member of the closing device, the shield constructed and arranged to enable access to the holding screws or nuts for demounting the vaporizer only when the closing device is in closed position. 
     
     
         64 . The delivery system of  claim 63  in which a spring loaded, pneumatically operable valve is mounted on the vaporizer to permit flow of vapor from the vaporizer, and the closing device is a mechanical over-riding device constructed to force the pneumatically operable valve to closed position regardless of presence of pneumatic pressure. 
     
     
         65 . The delivery system of  claim 58  wherein the vaporizer includes a normally closed pneumatic valve for controlling vapor flow from the vaporizer in response to a vaporizer control system and, for pneumatic connection, is connectable to a passage for compressed air associated with a mounting station having a sealing surface adapted to mate with a corresponding sealing surface of the vaporizer, each sealing surface surrounding ports for both the vapor flow and for the compressed air in the manner that sufficient connection for the compressed air for opening the pneumatic valve is dependent upon sealing together of the corresponding sealing surfaces, thereby to prevent opening of the pneumatic valve under a condition in which vapor can flow to the atmosphere. 
     
     
         66 . The vaporizer of  claim 58  constructed for use with a system constructed to be used with a set of different vaporizers that carry different solid feed materials, the vaporizer having a characteristic physical feature that denotes its contents, the physical feature suitable for recognition by a recognition system so that a vaporizer control system can operate under conditions appropriate for the contents of the recognized vaporizer. 
     
     
         67 . The vaporizer of  claim 66  carrying one or more switch actuator formations in unique pattern dependent upon the content to which the vaporizer is dedicated, suitable for interaction with a recognition system that comprises a set of actuatable switches. 
     
     
         68 . The vaporizer of  claim 66  and other vaporizers comprising a set dedicated respectively to different solid feed materials having different vaporization temperatures and different characteristic physical features for recognition. 
     
     
         69 . The vaporizer of  claim 68  in which one vaporizer in the set is dedicated to decaborane and another to octadecaborane. 
     
     
         70 . The vaporizer of  claim 68  in which one vaporizer in the set is dedicated to a borane and another vaporizer in the set is dedicated to a carborane. 
     
     
         71 . The vaporizer of  claim 58  having a temperature limit switch set to a safe temperature lying above normal vaporizing temperature and below a hazard temperature for the respective solid material to which the vaporizer is dedicated. 
     
     
         72 . The vaporizer of  claim 71  in which one vaporizer in the set is dedicated to decaborane and another to octadecaborane, and the temperature setting of the limit switches is about 5OC and 140 C, respectively. 
     
     
         73 . A heated vaporizer unit operable under reduced pressure to vaporize feed material and provide vapor to a further device, the vaporizer unit comprising a bottom section having side and bottom walls defining by their interior surfaces a feed material-receiving, vaporizing cavity and a top section defining a removable closure and a vapor passage for delivering vapor from the unit to the further device, the top and bottom sections constructed, when assembled, to engage at a vapor-tight interface, wherein
 both the top and bottom sections of the vaporizer canister unit are comprised of heat-conductive metal,   an electric resistance heater is located in the top section,   the top section is constructed and arranged to be a heat distributor to the interface with the bottom section,   the interface is heat conductive, adapted to transmit heat to the bottom section to vaporize the feed material,   and the side and bottom walls of the bottom section are constructed to distribute heat received from the interface to surfaces of the cavity exposed to the feed material to heat and vaporize the material as the material diminishes in quantity,   the unit constructed to establish a generally positive thermal gradient from vaporizing temperature at the bottom wall of the bottom section to a higher temperature at the vapor outlet passage in the top section.   
     
     
         74 . The vaporizer unit of  claim 73  in which at least the bottom section is constructed for use as a shipping container for the feed material. 
     
     
         75 . The vaporizer unit of  claim 73  in which the heater in the top section comprises a set of cartridge heater elements disposed with tight fit in openings in a metal body of the top section, the cartridge heater elements comprising substantially the sole source of heat for vaporizing the material in the bottom section. 
     
     
         76 . The vaporizer unit of  claim 73  wherein there is vaporizable feed material resident in the cavity of the bottom section, the material comprising solid material having low vapor pressure at room temperature. 
     
     
         77 . The vaporizer unit of  claim 76  in which the vaporizable solid material comprises molecules having multiple atoms of boron, carbon, phosphorus or arsenic. 
     
     
         78 . The vaporizer unit of  claim 77  in which the solid material is decaborane (B 10 H 14 ), the unit being constructed to maintain a temperature differential between the bottom wall of the bottom section to the vapor outlet passage in the top section of about 5 C. 
     
     
         79 . The vaporizer unit of  claim 77  in which the solid material is decaborane (B 10 H 14 ), the unit being associated with a control system constructed to heat the bottom wall of the bottom section over a decaborane vaporizing range up to an operating limit of about 40 C. 
     
     
         80 . The vaporizer unit of  claim 77  in which the solid material is decaborane (B 10 H 14 ), the unit being associated with an over-temperature limit switch having setting of about 50 C arranged as a safety device to prevent over heating of the top section of the unit. 
     
     
         81 . The vaporizer unit of  claim 77  in which the solid material is octadecaborane (B 18 H 22 ), the unit being constructed to maintain a temperature differential between the bottom wall of the bottom section to the vapor outlet passage in the top section of about 10 C. 
     
     
         82 . The vaporizer unit of  claim 77  in which the solid material is octadecaborane (B 18 H 22 ) the unit being associated with a control system constructed to heat the bottom wall of the bottom unit over an octadecaborane vaporizing range up to an operating limit of about 120 C. 
     
     
         83 . The vaporizer unit of  claim 77  in which the solid material is octadecaborane (B 18 H 22 ), the unit being associated with an over-temperature limit switch having setting of about 140 C arranged as a safety device to prevent over heating of the top section of the unit. 
     
     
         84 . The vaporizer unit of  claim 77  in which the material is a carborane. 
     
     
         85 . The vaporizer unit of  claim 84  in which the material is C 2 B 10 H 12 . 
     
     
         86 . The vaporizer unit of  claim 84  in which the material is C 4 B 12 H 22 . 
     
     
         87 . The vaporizer unit of  claim 73  in which the interface of the assembled unit is defined by a vacuum seal, and outwardly of the seal, by intimately contacting metal surfaces defined respectively by the top and bottom sections of the unit, the metal surfaces engaged with pressure, microscopic open interstices due to microscopic imperfections in the matching surfaces being filled by air from the atmosphere, the portion of the interface defined by the engaged metal surfaces providing the principal heat transfer path from the top section to surfaces of the bottom section that bound the material-receiving, vaporizing cavity. 
     
     
         88 . The vaporizer unit of  claim 87  in which the top and bottom sections define substantially planar matching surfaces at the interface, the matching surfaces forced together by an array of mounting screws, the bottom section comprising a generally cylindrical container having a side wall that is of substantially uniform thickness. 
     
     
         89 . The vaporizer unit of  claim 73  including a thermal detector located at the bottom wall of the unit and adapted to be connected to control the power to the heater in the top section to enable maintaining the temperature of the bottom wall of the unit at a selected set point. 
     
     
         90 . The vaporizer unit of  claim 88  including an electrical signal conductor extending from the detector to the interface between the top and bottom sections of the unit, the top and bottom sections carrying matching electrical connector portions in position to automatically engage with each other when the matching surfaces of the top and bottom sections are brought together. 
     
     
         91 . The vaporizer unit of  claim 90  in which the conductor is recessed in an upwardly extending groove in the surface of the thermally conductive wall of the bottom section. 
     
     
         92 . The vaporizer unit of  claim 89  associated with a closed loop temperature controller responsive to the thermal detector at the bottom wall of the unit to control the power to the heater in the top section to enable maintaining the temperature of the bottom of the unit at a selected set point. 
     
     
         93 . The vaporizer unit of  claim 73  in which the vapor passage in the heated top section has a vapor-receiving portion exposed to receive vapor from the vaporizing cavity, the initial portion extending generally upwardly, followed by a bend to a generally laterally extending vapor delivery portion. 
     
     
         94 . The vaporizer unit of  claim 93  in which the heater comprises cartridge heater elements extending generally parallel to the upwardly extending portion of the vapor passage, at least one cartridge heater element being located on each side of the laterally-extending delivery portion of the vapor passage, and at least one cartridge heater element being located on the side of the top section opposite from the direction of the laterally extending delivery portion of the passage the heater elements being in heat conductive relationship with surfaces defining the vapor passage. 
     
     
         95 . The vaporizer unit of  claim 93  in which a valve permitting vapor flow from the unit resides in the bend region of the vapor passage, surfaces of the valve being in heat conductive relationship with the heater. 
     
     
         96 . The vaporizer unit of  claim 95  in which the valve is a pneumatically operable bellows valve. 
     
     
         97 . The vaporizer unit of  claim 96  including a detachable fastening for mounting the unit at a mounting station of the further vapor-receiving device, and a hand-operable closing device, the closing device of the unit having a closed position that overrides the bellows valve and prevents vapor flow through the vapor passage, the closing device associated with an access-preventing device that prevents access of workers to the detachable fastening of a mounted vaporizer except when the closing device is in closed position, thereby to prevent flow of toxic vapor from the unit while the unit is being detached. 
     
     
         98 . The vaporizer unit of  claim 97  in which the detachable fastening comprises a pattern of holding screws engageable with mating fittings associated with the mounting station, and the access-preventing device comprises an access-preventing shield that moves dependently with a member of the closing device, the shield constructed and arranged to enable access to the holding screws for demounting the unit only when the closing device is in closed position. 
     
     
         99 . The vaporizer unit of  claim 73  in which the delivery portion of the vapor passage extends through an outward lateral projection constructed to interfit in a receptacle of predetermined construction of a further vapor-receiving device. 
     
     
         100 . The vaporizer unit of  claim 99  in which the outward lateral projection is constructed to bear the weight of the unit and serve as its support when the projection is engaged in the receptacle. 
     
     
         101 . The vaporizer unit of  claim 99  in which an end surface of the outward lateral projection is constructed to define a seal with a matching surface of the further vapor-receiving device. 
     
     
         102 . The vaporizer unit of  claim 101  having screw passages constructed to receive mounting screws capable of threading into the further device to force the end surface against the matching surface of the further device to establish a seal and provide stabilizing force. 
     
     
         103 . The vaporizer unit of  claim 99  for use with a further device that is maintained at a temperature different from that of the vaporizer unit, wherein thermal insulation insulates against heat transfer between the unit and the further device through the outward lateral projection. 
     
     
         104 . The vaporizer canister unit of  claim 103  in which the thermal insulation includes an insulative sleeve portion surrounding the projection and an insulative end portion disposed between the end of the projection and a wall defining a vapor-receiving passage of the vapor-receiving device. 
     
     
         105 . The vaporizer unit of  claim 99  in which, for making electrical connection between the unit and external control and power circuits, the vaporizer unit carries an electrical connector in a predetermined position to engage a matching connector of predetermined position on the further device, the predetermined position of the connector on the vaporizer unit enabling automatic connection of the connectors with movement of the vaporizer unit in direction to engage the lateral projection with the receptacle of the further device. 
     
     
         106 . The vaporizer-canister unit of  claim 105  in which the connector includes a connecting element for connecting compressed air to the unit for actuation of a pneumatic valve of the unit. 
     
     
         107 . The vaporizer-canister unit of  claim 105  in which the outward laterally extending projection has an alignment surface constructed to slideably engage a matching alignment surface of the receptacle of the further device to guide the engagement of the unit and the further device. 
     
     
         108 . The vaporizer unit of  claim 73  constructed to serve as a shipping canister in the absence of surrounding thermal insulation and to be disposed within thermal insulation during use as a vaporizer. 
     
     
         109 . A unit constructed as a heated release vessel or vaporizer to release or vaporize the material and provide the released gas or vapor to a further device, the unit defining a material-receiving region adapted to be heated by an electrical resistance heater of the unit and defining a gas or vapor passage for delivering gas or vapor from the unit to the further device, wherein a delivery portion of the vapor passage extends through an outward laterally extending projection constructed to interfit in a receptacle of predetermined construction  5  of a gas or vapor-receiving device, the lateral projection being constructed to bear the weight of the unit and serve as its support when the projection is engaged in the receptacle, an end surface of the projection constructed to define a seal with a matching surface of the further device, and wherein for making electrical connection between the unit and external o control and power circuits, the unit carries an electrical connector in a predetermined position to engage a matching connector of predetermined position on the further device, the predetermined position of the connector on the unit enabling automatic connection of the connectors with movement of the unit in direction to engage the lateral projection with the receptacle of the further device.  5   
     
     
         110 . The unit of  claim 109  constructed as a shipping canister for material to be dispensed or vaporized. 
     
     
         111 . The unit of  claim 109  in which the outward laterally extending projection  0  has an alignment surface constructed to slideably engage a matching alignment surface of the receptacle of the further device to guide the engagement of the unit with the further device. 
     
     
         112 . The unit of  claim 109  in which the connector includes a connecting element  5  for connecting compressed air to the unit for actuation of a pneumatic valve of the unit. 
     
     
         113 . The unit of  claim 112  in which a pneumatically operable bellows valve is disposed along the passage. 
     
     
         114 . The unit of  claim 113  including a detachable fastening for mounting the unit at a mounting station of the further device, and a hand-operable closing device, the closing device of the unit having a closed position that over-rides the bellows valve and prevents flow through the passage, the closing device associated with an access-preventing device that prevents access of workers to the detachable fastening of a mounted unit except when the closing device is in closed position, thereby to prevent flow of toxic gas or vapor from the unit while the unit is being detached. 
     
     
         115 . The unit of  claim 114  in which the detachable fastening comprises a pattern of holding screws engageable with mating fittings associated with the mounting station, and the access-preventing device comprises an access-preventing shield that moves dependently with a member of the closing device, the shield constructed and arranged to enable access to the holding screws for demounting the unit only when the closing device is in closed position. 
     
     
         116 . The unit of  claim 109  having screw passages constructed to receive mounting screws capable of threading into the further device to force the end surface against the matching surface of the further device to establish a seal and provide stabilizing force. 
     
     
         117 . The unit of  claim 109  for use with a further device that is maintained at a temperature different from that of the canister unit, and thermal insulation insulates against heat transfer between the unit and the further device. 
     
     
         118 . The unit of  claim 109  in the form of a vaporizer comprising a bottom section having side and bottom walls defining by their interior surfaces a feed material-receiving, vaporizing cavity and a top section defining a removable closure and a vapor passage for delivering vapor from the unit to the further device, the top and bottom sections constructed, when assembled, to engage at a vapor-tight interface, the outward laterally extending projection protruding from the top section. 
     
     
         119 . A vaporizer unit for solid material for use with an evacuated vapor-receiving system, the unit having a bottom section defining a solids-receiving vaporization volume, and a top section defining a closure, the top and bottom units being comprised of conductive metal a heater for the vaporizer being located solely in the top detachable closure section for heating surfaces at the bottom of the bottom section by heat conduction across an interface between the top and bottom sections and through peripheral side and bottom walls defining the bottom section. 
     
     
         120 . The vaporizer unit of  claim 119  in which the heater comprises cartridge heaters installed in recesses in the metal top section. 
     
     
         121 . The vaporizer unit of  claim 120  in which a vapor passage includes an axially-extending inlet section and a valve within the top section, the cartridge heaters comprising elongated elements extending parallel to and alongside of the inlet section and the valve in heat conductive relation therewith. 
     
     
         122 . A system comprising a vaporizer in combination with a flow interface device that defines a mounting station for removably receiving and communicating with the vaporizer, and an interlock system has structure that prevents accidental flow of toxic vapor to the atmosphere at the mounting station. 
     
     
         123 . The system of  claim 122  in which the vaporizer includes a detachable fastening for mounting the vaporizer at the mounting station and a hand-operable closing device, the closing device having a closed position preventing vapor flow from the vaporizer, the closing device associated with an access-preventing device that prevents access of workers to the detachable fastening of a mounted vaporizer except when the closing device is in closed position, thereby to prevent flow of toxic vapor from the vaporizer while the vaporizer is being detached. 
     
     
         124 . The system of  claim 123  in which the detachable fasteners comprise a pattern of holding screws or nuts engageable with mating fittings associated with the mounting station, and the access-preventing device comprises an access-preventing shield that moves dependently with a member of the closing device, the shield constructed and arranged to enable access to the holding screws or nuts for demounting the vaporizer only when the closing device is in closed position. 
     
     
         125 . The system of  claim 124  in which a spring loaded, pneumatically operable valve is mounted on the vaporizer to permit flow of vapor from the vaporizer, and the closing device is a mechanical over-riding device constructed to force the pneumatically operable valve to closed position regardless of presence of pneumatic pressure. 
     
     
         126 . The system of  claim 122  in which the interface device is constructed to be used with a set of different vaporizers that carry different solid feed materials that have different vaporization temperatures, the system including a recognition system arranged to recognize a characteristic physical feature of a mounted vaporizer that denotes its contents and to cause a vaporizer control system to operate under conditions appropriate for the contents of the recognized vaporizer. 
     
     
         127 . The system of  claim 126  in which the recognition system comprises a set of actuatable switches exposed to a vaporizer when the vaporizer is in mounted position, the set of switches adapted to cooperate with a vaporizer that carries one or more switch actuator formations in unique pattern dependent upon the content of the vaporizer. 
     
     
         128 . The system of  claim 126  including a set of more than one vaporizer unit, vaporizers of the set dedicated to containing respectively different solid feed materials having different vaporization temperatures, the vaporizer units having differing characteristic physical features for recognition. 
     
     
         129 . The system of  claim 122  in which an ion source is mounted within a vacuum chamber, the flow interface device constructed to transmit vapor for the ion source. 
     
     
         130 . The system of  claim 122  in which the ion source is in an ion implanter system to provide ions for implanting. 
     
     
         131 . The system of  claim 130  in which the ion source provides ions to a beam line for implanting in a target substrate. 
     
     
         132 . The vaporizer, vaporizer unit or vaporizer system of  claim 1  containing solid feed material capable of forming ionizable vapor and comprising a cluster molecule. 
     
     
         133 . The vaporizer, vaporizer unit or vaporizer system of  claim 132  in combination with an ion source capable of ionizing vapor produced from the solid material. 
     
     
         134 . The vaporizer, vaporizer unit or vaporizer system of  claim 1  containing solid feed material comprised of C 14 H 14 , C 16 H 10 , C 16 H 12 , C 16 H 2O , C 18 H 14  or C 18 H 38 . 
     
     
         135 . The vaporizer, vaporizer unit or vaporizer system of  claim 1  in which the solid feed material comprises a compound for N-Type doping. 
     
     
         136 . The vaporizer, vaporizer unit or vaporizer system of  claim 1  in which the solid feed material comprises an arsenic, phosphorus or antimony cluster compound. 
     
     
         137 . The vaporizer, vaporizer unit or vaporizer system of  claim 1  in which the solid feed material comprises an arsenic or phosphorus compound capable of forming ions of the form A n H x   +  or A n RH x   + , where n and x are integers with n greater than 4 and x greater than or equal to 0. and A is either As or P and R is a molecule not containing phosphorus or arsenic and which is not injurious to an ion implantation process. 
     
     
         138 . The vaporizer, vaporizer unit or vaporizer system of  claim 1  in which the solid feed material comprises a phosphorus compound selected from the group consisting of phosphanes, organophosphanes and phosphides. 
     
     
         139 . The vaporizer, vaporizer unit or vaporizer system of  claim 1  in which the solid feed material comprises P 7 H 7 . 
     
     
         140 . The vaporizer, vaporizer unit or vaporizer system of  claim 1  in which the solid feed material comprises an antimony compound that comprises a trimethylstibine. 
     
     
         141 . The vaporizer, vaporizer unit or vaporizer system of  claim 1  in which the solid feed material comprises S b (CHa)Cs. 
     
     
         142 . The method of treating a semiconductor device or semiconductor material comprising using the vaporizer, vaporizer unit or vaporizer system of  claim 132  to produce cluster ions, and using the ions in the treatment. 
     
     
         143 . The method of  claim 142  which the method of treating comprises ion implantation. 
     
     
         144 . The method of  claim 142  in which the method of treating comprises ion beam implantation.