Abstract:
Apparatus for trapping and collecting debris including an in-line trap contained in a subterranean chamber having an inlet and an outlet for connection to an underground conduit such as a sewer or storm drain conduit. The trap comprises a net being closed on all sides except on an inlet side which faces the inlet to the chamber. The chamber is contained in a vault having a set of upper doors and the bag is attached to a frame structure having suitable supports which may be grasped such that the bag may be lifted upwardly through the doors for replacement. An overflow weir is provided for allow flow past the trap when the bag is full of debris. Sensing systems are further provided for detecting and signalling when the bag is full. A multi-bag system is also disclosed in which at least two bags in parallel are provided such that one bag may accommodate overflow when the other is being serviced.
Abstract:
A sputtering target comprises a disc machined from a first piece of target grade material, having a front sputtering face and a rear face opposite. The sputtering face and target material erode during use to define a final sputtered face contour and a residual target thickness t measured from the rear face. A hub is machined from a second piece of material and is secured to the rear face of the disc. The securement device utilizes a depth of target material measured from the rear face which minimizes the thickness t in a region adjacent the hub so as to maximize the amount of the target grade material sputterable before in the region before encountering the securement device. In another form, the disc and hub are forged from a single starting slug of target grade material. The slug has an initial height to diameter ratio such that the flow lines developed in displaced target material during forging which turn upward from the disc into the hub are located at a depth of the target material measured from the rear face which also minimizes the thickness t so as to maximize the amount of the target grade material sputterable.
Abstract:
A re-entrant plug structure is disclosed which extends inside a processing chamber containing an ionized plasma in proximity to the plasma to physically displace the ionized plasma and selectively controllably vary concentration of ionized gas particles over the surface of a wafer to be sputter etched which is supported inside the chamber. The variation of concentration of the ionized plasma allows the selectively controllable variation of sputter etch rates on the surface of the wafer. The re-entrant plug structure may be formed as part of the enclosure cover of the processing chamber or may be a separable moveable unit which is inserted into the plasma through an opening in the processing chamber. The re-entrant plug may be of various lengths, diameters and shapes to displace and shape the ionized plasma. In an alternative embodiment of the invention, the plug contains a permanent or electromagnet which further magnetically displaces and shapes the plasma in addition to the physical displacement caused by the re-entrant plug.
Abstract:
An expendable target of sputter coating material is provided having secured thereto a storage medium having recorded thereon, in machine readable indicia, information relating to a characteristic of the target. The information preferably includes target identifying information and may also include information relating to the target composition, the history of the use of the target, and other information usable by the apparatus to automatically set machine parameters or to record process information. Information, particularly of the use of the target, may be updated and written to a medium on the target or target assembly, or to a machine readable medium which may be affixed to the target assembly when the target is removed. The apparatus preferably includes a read head in the sputtering chamber and may also include a write head for writing information to the target assembly. A memory and microprocessor cooperate with the machine control to utilize the information read from the target in the control of the sputtering apparatus.
Abstract:
Thickness uniformity of films sputtered from a target onto a series of substrates is maintained as the target surface shape changes due to the consumption of the target. The eroded condition of the target is sensed by directly measuring the position of a point on the target surface, by measuring power consumption of the target, by measuring deposition from the surface of the target or by some other means. A controller responds to the measurement by moving a substrate holder to determine an amount to change the distance between the substrate and the target, usually by moving the substrate closer to the target, by an amount necessary to maintain uniformity of the coatings on the wafers being processed. A servo or stepper motor responds to a signal from the controller to move the substrate holder in accordance with the determined amount of distance change required. The adjustment is made following the coating of wafers at various times over the life of the target.
Abstract:
An apparatus is disclosed for clamping a substrate or wafer with a predetermined force during a sputtering process for maintaining a minimal gap between the wafer and a backplane in order to provide a uniform temperature distribution on the wafer. The apparatus includes a first suspension system which includes a diaphragm having a plurality of spring sections positioned in contact with an outer peripheral area of an upper surface of the wafer. The spring sections are positioned immediately adjacent to each other to provide substantially continuous and uniform loading of the outer periphery in order to eliminate edge gaps. The apparatus further includes a second suspension system which includes a mounting ring having a plurality of springs each of which are secured to a fixed element. The first and second suspension systems are configured such that approximately 80 to 90% of the total spring deflection is provided by the second suspension system whereas the remaining 10 to 20% of the total spring deflection is provided by the first suspension system.
Abstract:
A composite backing plate (34) for a backing plate-target assembly (41) having a core of structural material (36) with a front face (42) and/or a rear face (44) of a different material laminated thereto. The composite backing plate (35) has the desired mechanical properties of a solid copper backing plate, for example, strength and stiffness, but is preferably less than half the density of a solid copper backing plate. The core material is preferably aluminum; the front face is preferably copper; and the rear face is preferably either copper or an organic material.
Abstract:
Method and apparatus for cooling a sputtering target is provided. The method comprises the steps of providing a sputtering target and a cooling surface in operable conductive heat transfer contact with the sputtering target, introducing a cooling liquid onto the cooling surface to conductively remove heat from the sputtering target, allowing at least a portion of the cooling liquid to change phase into a vapor, and preventing a continuous insulating vapor layer from forming on the cooling surface to ensure continuing conductive heat transfer from the target to the cooling surface so as to avoid overheating of the target. The apparatus comprises a cooling surface in operable conductive heat transfer contact with the sputtering target to conductively remove heat from the target when a cooling liquid is introduced onto the cooling surface, and means for allowing at least a portion of the cooling liquid to change phase into a vapor while preventing a continuous insulating vapor layer from forming on the cooling surface to ensure continuing conductive heat transfer from the target to the cooling surface so as to avoid overheating of the target.
Abstract:
A sputtering apparatus for forming a thin film on a substrate is disclosed. The sputtering apparatus includes a target for providing target material for forming the thin film, wherein the target includes a first area. The sputtering apparatus further includes a plasma discharge to enable removal of target material from the target. In addition, a main magnet is provided for generating a main magnetic field for controlling the plasma discharge to remove the target material. Further, a compensating magnet is utilized which is positioned adjacent to the first area. The compensating magnet generates a compensating magnetic field which interacts with the main magnetic field to control the plasma discharge in the first area to form a desired erosion pattern in the first area and enable formation of a substantially uniform film thickness on the substrate.
Abstract:
A sputtering target and target assembly includes a target member having a substantially continuously concave top surface and a bottom surface with a central, downwardly directed hub and at least three annular regions of differing radius of curvature. The shape of the target member bottom surface conforms to a backplate to which it is mounted, thereby facilitating accurate mounting of the target member during sputtering. The corresponding shapes of the target member and backplate promote maximum utilization of sputtering material.