Abstract: The cleaning compositions of the present invention comprise pyridine or substituted pyridines alone or in admixture with sulfoxides. Preferred compositions comprise pyridine and dimethylsulfoxide (DMSO). Any concentration of DMSO from 0-50% can be used, but preferred compositions contain 5-25% DMSO. The present invention is employed to treat integrated circuit modules enclosed in a cap or can. Following treatment the cap or can, which is sealed to the substrate by means of the cured epoxy, can be removed to allow rework. The preferred method of removing the cured epoxy from module substrates is by refluxing in the solution. The cured epoxy is totally removed and there is no attack of the Al-Cu or Sn-Pb metallurgies or chip polyimide passivation. The silicone overcoat material is not removed from behind the chips, eliminating the need to reapply the material after rework.

Abstract: The present invention provides an improved etchant composition and method for the resistivity specific etching of doped silicon films which overlie intrinsic or lightly doped crystal regions. The composition of the etchant is 0.2-6 mole % hydrofluoric acid, 14-28 mole % nitric acid, and 66-86 mole % acetic acid/water. The etchant leaves no silicon residue and provides for controlled etching with an etch stop at the lightly doped or intrinsic region.

Abstract: A method of improving the adhesion between a synthetic substrate and metallized layers deposited thereon. A glass resin layer is spin-coated onto an epoxide substrate. The glass layer is covered by a photoresist layer which is roughened by reactive ion etching. The roughened contour of the photoresist layer is transferred via reactive ion etching to form a perforation pattern in the glass layer. The substrate is then etched vertically and horizontally to produce recesses in the substrate having overhanging walls. A thin copper layer is sputtered onto the substrate and copper conductors are sputtered onto the thin copper layer, the copper layers filling the recesses. The recesses and overhangs form mortices in the substrate, and the copper layers within the recess form tenons which fittingly engage with the mortices to produce adhesion between the substrate and the metallized layers in the order of 1000 n/m.

Abstract: An improved flexible leader for use in conveying ink ribbon from a ribbon box to the print point of a printer or typewriter is disclosed. The leader is a U-shaped channel with top latches which protects the ribbon from operator contact and provides good ribbon tracking. Vertical raised ridges on the insides of the channel reduce frictional contact between the ribbon and the leader. The leader is easy to install.

Abstract: A sealing apparatus in a magnetic brush development device is located in a non-contact fashion between the photoconductor drum and the magnetic brush roll. The seal has a plurality of ridges along the length of the seal that creates a differential air flow under the rotating photoconductor drum. This differential air flow prevents toner dust and bead carryout from axially migrating past the end of the photoconductor and magnetic roll.

Abstract: Apparatus in a vacuum deposition system positions a workpiece holder in substantial alignment with a source of material to be deposited onto a work piece affixed to the workpiece holder. The apparatus also rotates the workpiece holder about the deposition source and linearly drives the workpiece holder to varying distances from the deposition source. The apparatus used to drive the workpiece holder is sealably mounted atop an opening in the vacuum chamber. The apparatus enables multiple source depositions to be carried out consecutively without accessing the vacuum chamber. By aligning the workpiece holder over the deposition source, nonuniform deposition onto the workpiece is substantially eliminated.

Abstract: Method and apparatus for automatic optical inspection of a substantially two-dimensional pattern using digital image processing techniques are described. In a first processing step, all regions of a digitized stored image derived from the two-dimensional pattern are scanned for edges or lines, that is, transitions between regions having optically different characteristics. The scanned edge regions are marked in the image storage. In a subsequent second processing step all non-marked regions of the image storage are scanned and tested for the presence of permissible grey levels. A meander-shaped scanning track is used for scanning the edge or lined regions. The apparatus for implementing this method includes special latch circuitry for eliminating the further processing of marked regions, thus increasing the overall speed at which the two-dimensional pattern can be optically inspected.

Abstract: An optical photolithographic process in which resist lines having widths in the micron and sub-micron range are produced without the use of a fine line photomask. A positive photoresist having an additive for image reversal is applied to the surface of a semiconductor substrate. The photoresist is exposed through a photomask to ultraviolet light. The edges of the opaque sections of the mask diffract the ultraviolet light, forming partially exposed areas between the exposed and unexposed areas formed in the photoresist. After development in a solvent to remove the exposed areas, the photoresist undergoes an image reversal process. The photoresist is first baked at 100.degree. C. for 30 minutes. During this bake step, the photoactive decomposition products present in the partially exposed areas react, freezing the solubility of the partially exposed areas with respect to that of the unexposed areas.

Abstract: A ZIF connector block for establishing an electrical connection between the I/O pads of an edge-connected printed circuit board and a set of printed conductors. The connector has two opposing rows of contacts. The contacts are of two different lengths, both adjacent and opposite ones of the contacts having different lengths. An upper housing has a plurality of cams mounted thereon, each cam having a different cam surface profile. The surface profiles of the cams are staggered into two different lengths corresponding to the lengths of the contacts so that when the cams are actuated by imparting a vertical motion to the upper housing, the contacts will simultaneously engage the I/O pads in a staggered fashion. Moreover, the surface profiles of the cams are constructed so that after simultaneous engagement, the contacts perform sequential wipe cycles on the pads. The staggered and sequential wipe cycles promote the stability of the board within the connector without sacrificing electrical integrity.