Memory including two access devices per phase change element
AssigneesQimonda North America Corp., International Business Machines Corporation, Macronix International Co., Ltd.
InventorsThomas Nirschl, Roger Cheek, Mark Lamorey, Ming-Hsiu Lee
Life of this patent
Estimating the term…
Abstract
A memory includes a bit line and a phase change element. A first side of the phase change element is coupled to the bit line. The memory includes a first access device coupled to a second side of the phase change element and a second access device coupled to the second side of the phase change element. The memory includes a circuit for precharging the bit line and one of selecting only the first access device to program the phase change element to a first state and selecting both the first access device and the second access device to program the phase change element to a second state.
Claims27
A memory comprising:
- a bit line;
- a phase change element, a first side of the phase change element coupled to the bit line;
- a first access device coupled to a second side of the phase change element;
- a second access device coupled to the second side of the phase change element;
- and
- a circuit for precharging the bit line and one of selecting only the first access device to program the phase change element to a first state and selecting both the first access device and the second access device to program the phase change element to a second state.
A memory comprising:
- a bit line;
- a phase change element, a first side of the phase change element coupled to the bit line;
- a first access device coupled to a second side of the phase change element;
- a second access device coupled to the second side of the phase change element;
- and
- a circuit for precharging the bit line and one of selecting the first access device to program the phase change element to a first state and selecting the second access device to program the phase change element to a second state.
A memory comprising:
- a bit line;
- a phase change element, a first side of the phase change element coupled to the bit line;
- first means coupled to a second side of the phase change element for accessing the phase change element;
- second means coupled to the second side of the phase change element for accessing the phase change element;
- and
- means for precharging the bit line to a first voltage and one of selectively activating one of the first means and the second means individually and activating the first means and the second means simultaneously to program the phase change element to one of a first state and a second state.
A method for programming a memory cell, the method comprising:
- precharging a bit line coupled to a first side of a phase change element;
- and
- one of selecting a first access device coupled to a second side of the phase change element to program the phase change element to a first state and selecting the first access device and a second access device coupled to the second side of the phase change element to program the phase change element to a second state.
A method for programming a memory cell, the method comprising:
- precharging a bit line coupled to a first side of a phase change element;
- and
- one of selecting a first access device coupled to a second side of the phase change element to program the phase change element to a first state and selecting a second access device coupled to the second side of the phase change element to program the phase change element to a second state.
Dependencies are inferred from the claim text.