Burroughs, Inc.

National Semiconductor Corporation

Visic, Inc.

Joel A Karp

John A Reed

Ilbok Lee

Donald L Henderson, Sr

Steven M Baldwin

Charles E Boettcher

Andrew G Varadi

Dennis J Logwood

Mohammed E Haq

A memory array of four-IGFET-transistor cells arranged in rows and columns. The array uses two patterned metal layers and two patterned poly-silicon layers. For each column there is a pair of metal differential bit lines, formed on a first patterned metal layer. For each row there is a pair of split equipotential poly-silicon word lines and a parallel metal word line with connections to the split poly word lines at defined intervals. The parallel metal word line is on a second patterned metal layer distinct from the metal layer used for the bit lines. A grounded poly-silicon plate overlies the capacitive memory nodes of said array. The grounded poly-silicon plate is on a second patterned poly-silicon layer distinct from the poly-silicon layer used for the split word lines. The poly-silicon plate is connected to the circuit ground at defined intervals. Also, the poly-silicon plate provides alpha particle protection to the array and helps decouple the bit lines from the capacitive nodes of the array.

MOS/CMOS memory cell

There is provided an improved MOS dynamic random access memory (DRAM) device having an array of dynamic RAM cells accessed by word and bit lines. Each memory cell comprises a single field-effect transistor coupled by its source to the gate of an MOS storage capacitor. The word lines are coupled to their respective memory cells at the gate of the field-effect transistor therein, while the bit lines are coupled to their respective memory cells at the drain of the field-effect transistor. The bit lines are organized into pairs of adjacent polysilicon lines that are coupled to all the memory cells on both sides of the bit lines in an alternating configuration. The word lines are coupled to alternating pairs of cells on opposite sides of the word lines.

Dynamic RAM memory

A semiconductor memory is comprised of a semiconductor substrate having first and second spaced apart arrays of memory cells disposed thereon. A plurality of first pairs of bit lines couple to the cells of the first array, and a corresponding plurality of second pairs of bit lines couple to the cells of the second array. Disposed between each first pair and corresponding second pair of bit lines is one X sense amplifier. This amplifier includes a set node selectively coupled to one bit line of the first pair and to one bit line of the second pair, and a reset node selectively coupled to the opposite bit lines of the first and second pair for selectively sensing charge on the four bit lines.

X Sense AMP memory

An IGFET integrated circuit memory cell structure utilizing a capacitor with increased charge storage capability, and a method making the same. The capacitor includes a high impurity concentration region having the same conductivity type as the substrate. An island of opposite conductivity type is inset in the region and a conductive field plate overlies the island. The structure also includes a transfer transistor in which the source region is adjacent the capacitor and overlaps the island region therein. Activation of the transistor serves to transfer the charge stored in the capacitor to the drain region where it can be read by external circuitry. In the method, the high concentration region and island in the capacitor are formed by successive ion implantation steps. A subsequent source and drain diffusion causes lateral migration of the conductive portions of the cell to increase the storage capacitance and to insure electrical contact between the island region of the capacitor and the source of the transfer transistor.

IGFET integrated circuit memory cell

IGFET Integrated circuit memory cell

In a memory circuit, first and second bit line portions, each having a plurality of memory cells coupled thereto are provided for reading and writing electrical potentials into and out of the coupled memory cells. A bistable flip-flop type sensing amplifier is coupled between the first and second bit portion for sensing the voltage difference therebetween and for latching into one of the two states in response to sensing either a '0' or a '1' accessed to one of the bit line portions from an addressed memory cell to be read out of the memory. A high input impedance amplifier is provided between the respective bit line portion and the respective input terminal of the sensing amplifier for isolating (buffering) the stray capacitance of the sensing amplifier circuit from the capacitance of its bit line. Switchable restore circuitry bypasses each of the isolating line amplifiers for the purposes of restoring electrical potentials read out of the addressed memory cells. In a preferred embodiment, the buffer line amplifiers comprise source follower amplifiers.

MOS Dynamic random access memory having an improved sensing circuit

This disclosure relates to a high impedance regenerative differential sense amplifier for use with an integrated circuit memory array of single transistor cells. Each of the sense amplifiers is formed of a cross coupled latch connected to the respective columns by source followers and leads from the latch drive write back gates coupled to the respective columns so as to restore a 'zero' level of a cell and also leave a precharged 'one' level with the cell by charging the appropriate column. The respective columns are initially precharged and balanced and then driven by negative going signals.

Ultra high sensitivity sense amplifier for memories employing single

This disclosure relates to memory array organization of single transistor cells and the differential sense amplifiers provided therewith. To accommodate the differential sense amplifiers, the array is laid out in rows and functional columns where a functional column consists of a pair of columns such that odd row cells are connected to the odd column of the pair and even row cells are connected to the even column of the pair. A differential sense amplifier is then provided for each pair of odd and even columns which are inherently balanced at the sense amplifier terminals. Single ended or edge ended I/O circuitry is provided with direct access to the respective pairs of columns.

Growing community of inventors

Palo Alto, CA, United States of America

Joel A Karp