A control device matrix comprising: a two dimensional array of conductive elements crossing one another but insulated at a plurality of points, current control device adjacent each of said points and each including electron emitting means disposed between the elements at the points and electrically connected with at least one of the conductive elements thereat and a discrete body of normally insulative switch-forming amorphous semiconductor material at each of said points. Primary circuit means are provided defining discrete circuit paths through the body of said switch-forming amorphous semiconductor material of each current control device. Circuits are provided for selectively actuating the electron emitting means of each current control device to selectively switch the bodies to a more conductive state by injecting high energy charge carriers into the bodies.
This application is a continuation-in-part of application Ser. No. 139,004 filed Apr. 30, 1971, abandoned, entitled "Multi-Terminal Amorphous Electronic Control Device", and a division of application Ser. No. 184,179 filed Sept. 27, 1972, now U.S. Pat. No. 3,748,501.
Certain structures are described for solid state electrical switches which employ electrochromic material. These structures involve use of a common base contact for both switching and readout circuits. The structures are particularly easy to fabricate using integrated circuit techniques and exhibit reduced electrical shorts due to reduced migration of metallic ions.
A method of making thin film devices with selective etchants. Specifically, a fabrication process in accordance with the invention provides for the manufacture of amorphous chalcogenide sandwich structures. Such structures consist of a glass substrate, a chromium or aluminum electrode on the substrate bounding one side of the chalcogenide layer, and a second electrode of aluminum bounding the other side of the chalcogenide layer. First, the aluminum electrode is etched without affecting the other layers. Secondly, the chalcogenide layer is etched with a solution which attacks only the chalcogenide material and neither the overlying aluminum nor the underlying chromium or aluminum electrode. This two-step process is particularly suitable for fabricating current controlled negative differential resistance devices which requires the precise registration of one of the electrodes with the boundary of the chalcogenide such that a coextensive boundary is achieved.
An electronic device for securing the contents of data storage and processing elements. The device includes a security element and a phase-change element connected in a parallel arrangement. The security element is a three-terminal device, having an ON state and an OFF state which differ in resistance and regulate electronic access to the phase-change element by controlling the flow of electrical current applied to the parallel combination. In the ON state, the resistance of the security element is less than that of the phase-change element, thereby precluding a determination of the resistance of the phase-change element. In this PROTECT mode, the contents of the phase-change element are secured. In the OFF state, the resistance of the security element is greater than that of the phase-change material so that the resistance of the parallel combination approaches that of the phase-change element. In this READ mode, the resistance and information content of the phase-change element can be determined.
