摘要:
An extrusion die is described for extruding a polymer from a reactive precursor mixture without plugging of the die. The extrusion die includes a die inlet leading to at least one channel having dimensions which produce a wall shear stress value that exceeds the critical wall shear stress value for the particular reactive precursor mixture to prevent occlusion of the die. The preferred configuration of the die channels is a tree-like structure to obtain a coating width which is greater than the dimensions of the individual channels. Other features of the invention include a method for determining the critical wall shear stress value and a method for extruding reactive precursor mixtures.
摘要:
A sealable enclosure for wafers has a door with an easily accessible and disassembleable latching mechanism which utilizes a minimal number of moving parts. The door includes an enclosure with a cammed member rotatable on a post and in engagement with a pair of latching arms that extend, retract, move upwardly and downwardly or forwardly and rearwardly depending on whether the door is a front side door or a bottom door. The movement of the latching arms is accomplished by cammed portion of the cammed member configured to move cam follower portions of the latching arms in an axial direction with respect to the cammed member and in a radial direction. The latching arm pivots on a fulcrum within the enclosure. The latching mechanism is accessible through a panel that attaches by integral detents on the panel that cooperate with recesses on the interior edge walls of the door enclosure. The rotatable member has a slotted center and is secured on a T-shaped post extending from the enclosure by placement on the post in an insertion rotational position. When assembled the rotation of the cammed member is restricted to the operative range by stops on the enclosure.
摘要:
A dimensionally stable and static dissipative carrier for semiconductor wafers or magnetic storage disks that has exceptionally low particle generation characteristics. The carrier having opposing side walls and connecting walls, the side walls having ribs defining slots for axial arrangement of the disks or wafers. The side walls, ribs, and end walls are all integral and formed of injection molded polybutyl terephtahalate (PBT) with sufficient carbon fiber filler for a surface resistivity less than 10.sup.12 ohms per square.
摘要:
A rheological device suitable for measuring the rate of polymerization of ultraviolet sensitive polymers includes a part of open-ended cylindrical fixtures having removable quartz windows at one end. The upper fixture is adapted with a window which permits light to enter and impinge upon the surface of an elliptically-shaped mirror. Curing is monitored by measuring the elastic and viscous moduli during polymerization.
摘要:
A container and a method of storing semiconductor wafers, wherein a closed container has sealed top and bottom portions of molded plastic material and uniquely adapted for storing semiconductor wafers, the container having, in one of its parts, a gas receiving stem and valve for removing a portion of the gaseous atmosphere within the container as to store the semiconductor wafers in a partial vacuum, one portion of the container may incorporate a thin wall of the molded container comprising a flexible membrane adjacent edges of the semiconductor wafers to be drawn against the wafers and hold them in place within the container; the walls of the closed container being covered with a diamond-like coating; and a method of storing semiconductor wafers by confining the wafers in a multipart container, sealing the container, and modifying the atmosphere within the container as by reducing the gas pressure within the container, changing the gaseous atmosphere in the container by, in some cases, substituting an inert gas for the air within the container, and relieving the vacuum pressure within the container as the container is to be opened, by supplying clean air into the container with minimial particulate.