Abstract: The disclosure describes a technique whereby the electrical characteristics of an electrical circuit in a package may be adjusted to a predetermined value by changes in the dielectric structure between two levels of circuitry.This adjustment in the composite dielectric structure is accomplished by changes in the electrical properties of the composite dielectric material, one level being preset to a value and the other level being adjusted by alterations of predetermined amounts that depend upon the performance desired.

Abstract: An electronic packaging structure includes a second level electronic package having at least one opening formed therein and circuitry for electrical connection to a semiconductor chip. A circuitized polyimide film chip carrier includes at least one semiconductor chip mounted on one major surface thereof and at least one decoupling capacitor mounted on an opposite surface thereof. The decoupling capacitor is electrically coupled to input/output contacts of the semiconductor chip. The carrier is then mounted on the second level electronic package so that one semiconductor chip is positioned within a respective opening and the circuitry formed on the carrier is coupled to the circuitry formed on the second level package thereby interconnecting the semiconductor chip to the electronic package.

Abstract: A system for measuring the lateral displacement between edges located on two spaced apart objects, with a precision in the order of 1 microinch, generates and analyses the diffraction pattern produced by the physical edge on one object and the aerial image of the edge on the other object. The system can be used for the alignment of the objects or the comparison of patterns located on the objects.

Abstract: A spot of collimated monochromatic radiation is applied to a semiconductor wafer to obtain a diffraction pattern from two edges within an area, which is the size of the spot, on the wafer. The diffraction pattern is reflected to a photodiode array wherein the light intensity of the diffraction pattern at each of a plurality of positions is obtained. Each of the photodiodes is scanned separately for the same period of time to determine the light intensity at its location. The distance between the zero intensity positions on the photodiode array is determined very precisely and utilized with the wavelength of a laser, which supplies the spot of collimated monochromatic radiation, and the effective focal length of the lens system, which images the diffraction pattern to the photodiode array, to calculate the linear distance between the edges.