Abstract:
A memory device comprises a first selector and a storage capacitor in series with the first selector. A second selector is in parallel with the storage capacitor coupled between the first selector and zero volts. A plurality of memory devices form a 2S-1C cross-point DRAM array with 4F2 or less density.
Abstract:
Techniques are disclosed for forming resistive random-access memory (RRAM) including a tunnel source access transistor, such as a tunnel source MOSFET. The use of a tunnel source access transistor includes integrating a tunnel diode on the bitcell transistor's source terminal using epitaxial growth. Accordingly, such RRAM bitcells are referred to herein as having a 1T(D)-1R configuration. As can be understood based on this disclosure, the tunnel diode's resistance is asymmetric with respect to RRAM write voltage. Thus, the tunnel diode optimizes array operations for the 1T(D)-1R bitcells described herein, enabling both control of current compliance in the SET direction and maximization of current in the RESET direction from the same RRAM bitcell. The 1T(D)-1R architecture is compatible with a multitude of RRAM device structures and transistor types, such as NMOS and PMOS configurations. Further, the tunnel diode can be integrated in a MOSFET access transistor without increasing cell layout area.
Abstract:
The present techniques generally relate to correlated electron switch elements and, more particularly, to controlling current through correlated electron switch elements during programming operations.
Abstract:
A ReRAM cell array has rows and columns and includes first and second complementary bit lines for each row, a first, second and third word lines for each column and a source bit line for each row. A ReRAM cell at each row and column includes a first resistive memory element, its first end connected to the first complementary bit line of its row, a p-channel transistor, its source connected to a second end of the first resistive memory element, its drain connected to a switch node, its gate connected to the first word line of its column, a second resistive memory element, its first end connected to the second complementary bit line of its row, an n-channel transistor, its source connected to a second end of the second resistive memory element, its drain connected to the switch node, its gate connected to the second word line of its column, and a programming transistor having a drain connected to the switch node, a source connected to the source bit line of its row and a gate connected to the third word line of its column.
Abstract:
A memristive crossbar array is described. The crossbar array includes a number of row lines and a number of column lines intersecting the row lines to form a number of cross points. A number of memristor cells are coupled between the row lines and the column lines at the cross points. A memristor cell includes a memristive memory element to store information and multiple selectors electrically coupled to the memristive memory element. The multiple selectors are to provide access to the memristive memory element.
Abstract:
In one embodiment, a semiconductor memory device includes a plurality of resistive switching memory cells, where each resistive switching memory cell can include: (i) a programmable impedance element having an anode and a cathode; (ii) a word line pair configured to control access to the programmable impedance element, where the word line pair comprises first and second word lines; (iii) a PMOS transistor having a source coupled to the cathode, a drain coupled to a bit line, and a gate coupled to the first word line; and (iv) an NMOS transistor having a source coupled to the bit line, a drain coupled to the cathode, and a gate coupled to the second word line.
Abstract:
Im Rahmen der Erfindung wurde ein Verfahren zum Auslesen eines nichtflüchtigen Speicherelements mit mindestens zwei stabilen Zuständen 0 und 1 entwickelt. Dieses umfasst mindestens eine resistive Speicherzelle, die die beiden Zustände 0 und 1 in einen Zustand HRS mit höherem elektrischem Widerstand und einen Zustand LRS mit niedrigerem elektrischem Widerstand kodiert. Das Speicherelement weist in den beiden Zuständen 0 und 1 unterschiedliche Kapazitäten C 0,1 auf; über diesen Unterschied wird bestimmt, welcher Zustand vorliegt. Erfindungsgemäß wird ein Speicherelement gewählt, in dem eine vom Zustand der Speicherzelle unabhängige Festkapazität mit der Speicherzelle in Reihe geschaltet ist. Es wurde erkannt, dass eine Reihenschaltung einer resistiven Speicherzelle mit einer Festkapazität statt mit einer zweiten resistiven Speicherzelle die Signalstärke beim kapazitiven Auslesen verbessert. Es wurde außerdem erkannt, dass die zweite Speicherzelle für die Speicherfunktion entbehrlich wird, wenn das Speicherelement kapazitiv ausgelesen wird. Im Rahmen der Erfindung wurden zudem Speicherelemente entwickelt, die einen Feldeffekttransistor bzw. eine DRAM-Struktur mit einer resistiven Speicherzelle oder einer antiseriellen Reihenschaltung derartiger Speicherzellen kombinieren. Derartige Speicherelemente sind besonders zur Durchführung des erfindungsgemäßen Verfahrens geeignet.