Abstract: An environmental scanning electron microscope which achieves image resolution comparable to that of a conventional SEM. A biased ring electrode which detects secondary electron signals emanating from the surface of the specimen is provided in the specimen chamber. A biased pressure limiting aperture electron detector is also provided to reduce signals emanating from backscattered electrons and to reduce signal noise generated by the electron beam. This environmental SEM also optimizes the signal amplification of the secondary electrons following detection thereof, such that the detector noise is reduced below the noise in the signal itself, while still maintaining an overall bandwidth that is suitable for setting up the image. An optical window system is also provided in this environmental SEM which allows the user to easily switch between the normal environmental SEM electron image (limited to 0.5 mm in diameter) to an optical light view of the sample that covers a field-of-view of up to about 7 to 10 mm.

Abstract: An ion beam treatment system for treating silicon wafers placed in the ion beam path. A rotatably mounted wafer pedestal has a plurality of wafer supporting substrates spaced about the pedestal. The substrates are constructed from an elastomer that is chosen for its ability to transfer heat generated by ion collision with the wafers away from the wafers. Each wafer substrate defines a series of elongated depressions across its surface. Certain of these depressions are connected to a pressure source at a wafer loading/unloading station to help acquire the wafers during loading and to facilitate removal of the wafers during unloading. Other depressions vent the interface between the wafers and the substrate to atmosphere to avoid undue pressure build-up on the wafers as they lift off the substrate.

Abstract: A target chamber for a mechanically scanned ion implanter in which semiconductor wafers are maintained in contact with a rotating target disk entirely by body forces, thus eliminating the need for clamping members contacting the wafer surface. The axis of the disk is inclined, and the disk is in the form of a shallow dish having an inclined rim with cooled wafer-receiving stations formed on the inner surface of the rim. Centrifugal force is relied on to force the wafers against the cooled disk. Each wafer-receiving station includes fence structures which are engaged by the wafer during loading and when the disk is spinning. The fence structures are resilient so that wafer damage and thus particulate contamination is minimized. In accordance with another aspect of the invention the ion beam is projected against the wafers obliquely to the radius of the disk as to minimize striping effects and overscan.

Abstract: Peripherally-driven scroll apparatus. The orbiting scroll member is attached through radially-compliant linking means to eccentrics mounted on three equally spaced crankshafts to accommodate differential thermal expansion without the generation of any appreciable elastic forces to increase bearing loads. Means are provided to prevent axial deflections in the stationary scroll members while permitting their supports to be designed and constructed for strength rather than stiffness. The apparatus may be staged and employed as a compressor or expander.

Abstract: The calipers of a brake assembly are sequentially displaced into engagement with the wheel rim of a bicycle at low and high leverage ratios respectively by a force applied through an actuating cable device. A preload spring force resisting displacement of the high leverage caliper is reduced by buckling of a toggle device when the actuating cable begins displacement of the caliper at the high leverage ratio.

Abstract: Multi-stage engagement of a bicycle wheel rim is effected by force simultaneously applied to a slidable caliper and a pivoted caliper causing sequential displacement of the calipers. Displacement of the slidable caliper at a low leverage ratio is terminated by a locking action in response to initial brake contact to cause subsequent pivotal displacement of the pivoted caliper at a high leverage ratio for increased braking contact with the wheel rim.

Abstract: A control mechanism adapted for incrementally and positively controlling the displacement of a biassed member or the like associated with a bicycle gear-change transmission between a plurality of predetermined positions for effectuating changes in gear ratios of such transmission in response to unidirectional movement of an operator control lever of the control mechanism. In addition, the control mechanism is also, preferably, provided with an "overshift" arrangement which effectively and effortlessly enables an operator to shift the bicycle sprocket chain from one sprocket to another sprocket of larger diameter. In an alternate embodiment, the control mechanism is directly mounted on and connected to a derailleur type bicycle change-gear mechanism.