Integrated circuit with a transitor over an interconnect layer
View Patent ↗An integrated circuit ( 101 ) includes electrical circuitry ( 105 ) formed on a substrate ( 103 ). An interconnect layer ( 109, 117 ) is formed over the electrical circuitry ( 105 ). In one example, a plurality of magneto-resistive random access memory cells (MRAM) ( 161, 171 ) is implemented above the interconnect layer. Each of the MRAM cells comprises a magneto-resistive tunnel junction (MTJ) storage element. A transistor ( 130 ) is formed-over the interconnect layer ( 109, 117 ). In one embodiment, the transistor is implemented as a thin film transistor (TFT). In one embodiment the transistor is a select transistor and may be coupled to one or more of the MTJ storage elements. Access circuitry ( 203, 205, 207, 209 ) is formed on the substrate ( 103 ) under the plurality of MRAM cells ( 161, 171 ).
1. An integrated circuit comprising:
a substrate having an electrical circuit formed thereon;
an interconnect layer formed over the electrical circuit; and
a thin film transistor (TFT) formed over the interconnect layer;
wherein the integrated circuit includes a memory having a plurality of memory cells and the electrical circuit is an access circuit for accessing the plurality of memory cells.
2. The integrated circuit of claim 1 , wherein the thin film transistor is for coupling at least one of the plurality of memory cells to a data path in response to receiving a select signal from the access circuit.
3. The integrated circuit of claim 1 , wherein the plurality of memory cells is characterized as being a plurality of magneto-resistive random access memory (MRAM) cells, each of the plurality of MRAM cells comprising a magneto tunnel junction (MTJ) storage element.
4. The integrated circuit of claim 3 , wherein a group of the plurality of MRAM cells is coupled to the thin film transistor.
5. The integrated circuit of claim 3 , wherein:
the thin film transistor is for coupling at least one of the plurality of memory cells to a data path in response to receiving a select signal from the access circuit;
the thin film transistor has a first current electrode coupled to an MTJ storage element of the at least one of the plurality of memory cells, a second current electrode coupled to a bitline, and a control electrode coupled to a wordline for receiving the select signal.
6. The integrated circuit of claim 5 , wherein the thin film transistor is coupled to an MTJ storage element of more ta one of the plurality of memory cells.
7. The integrated circuit of claim 6 , wherein the MTJ storage elements of the more than one of the plurality of memory cells are coupled together in parallel.
8. The integrated circuit of claim 1 , wherein the interconnect layer is one of a plurality of metal interconnect layers formed over the electrical circuit.
9. The integrated circuit of claim 8 , further, comprising a top metal interconnect layer formed over the thin film transistor.
10. An integrated circuit comprising:
a substrate having active circuitry formed thereon;
an interconnect layer formed over the substrate;
a plurality of memory cells formed over the interconnect layer; and
a transistor formed over the interconnect layer, the transistor for selectively coupling a memory cell of the plurality of memory cells to the active circuitry.
11. The integrated circuit of claim 10 , wherein the transistor is a thin film transistor (TFT).
12. The integrated circuit of claim 10 , wherein the active circuitry comprises an access circuit for coupling the plurality of memory cells to a data path.
13. The integrated circuit of claim 12 wherein the transistor is for coupling at least one of the plurality of memory cells to a data path in response to receiving a select signal from the access circuit.
14. The integrated circuit of claim 10 , wherein the plurality of memory cells is characterized as being a plurality of magneto-resistive random access memory (MRAM) cells, each of the plurality of MRAM cells comprising a magneto tunnel junction (MTJ) storage element.
15. The integrated circuit of claim 14 , wherein:
the active circuitry comprises an access circuit for coupling the plurality of memory cells to a data path;
the transistor is for coupling at least one of the plurality of memory cells to a data path in response to receiving a select signal from the access circuit;
the transistor has a first current electrode coupled to an MTJ storage element of at least one of the plurality of memory cells, a second current electrode coupled to a bitline, and a control electrode coupled to a wordline for receiving the select signal.
16. The integrated circuit of claim 14 , wherein the transistor coupled to MTJ storage elements or more than one cells of the plurality of memory cells, the more than one cells are coupled together in parallel.
17. The integrated circuit of claim 10 , wherein the interconnect layer is one of a plurality of metal interconnect layers formed over the substrate.
18. The integrated circuit of claim 17 , further comprising a top metal interconnect layer formed over the transistor.
19. An integrated circuit comprising:
a substrate having active circuitry formed thereon, wherein the active circuitry includes a plurality of transistors;
an interconnect layer formed over the substrate including over the active circuitry; and
a transistor formed over the interconnect layer.
20. The integrated circuit of claim 19 , wherein the transistor is a thin film resistor (TFT).
21. The integrated circuit of claim 19 wherein the plurality of transistor are CMOS transistors.
22. The integrated circuit of claim 19 wherein each of the plurality of transistors includes a source/drain region formed by doping material or the substrate.