Ultra dense vertical transport FET circuits

Patent metadata

Field	Value
Publication number	US-9954529-B2
Application number	US-201715464696-A
Country	US
Kind code	B2
Filing date	Mar 21, 2017
Priority date	Feb 18, 2016
Publication date	Apr 24, 2018
Grant date	Apr 24, 2018

Abstract

Logic circuits, or logic gates, are disclosed comprising vertical transport field effect transistors and one or more active gates, wherein the number of C PP 's for the logic circuit, in isolation, is equal to the number of active gates. The components of the logic circuit can be present in at least three different vertical circuit levels, including a circuit level comprising at least one horizontal plane passing through a conductive element that provides an input voltage to the one or more gate structures and another conductive element that provides an output voltage of the logic circuit, and another circuit level that comprises a horizontal plane passing through a conductive bridge from the N output to P output of the field effect transistors. Such logic circuits can include single-gate inverters, two-gate inverters, NOR2 logic gates, and NAND3 logic gates, among other more complicated logic circuits.

First claim

What is claimed is:

1. A logic circuit comprising:
a first vertical transport field effect transistor and a second vertical transport field effect transistor, each having source/drain regions on vertically opposing sides of a gate structure and a vertical fin extending vertically upwards with respect to a supporting substrate of a vertical inverter, from a bottom source/drain region to a top drain/source region;
one or more gate structures;
wherein components of the logic circuit are present in at least three different and distinct vertical levels, a Level FET comprising a horizontal plane passing through the fins of the first and second vertical transport field effect transistors, Circuit Level M 1 , and Circuit Level M 2 ;
wherein Circuit Level M 1 comprises at least one horizontal plane through at least one conductive element that provides an input voltage to the one or more gate structures and another conductive element that provides an output voltage of the logic circuit; and
wherein Circuit Level M 2 comprises a horizontal plane through at least one conductive element that forms a conductive bridge from N output to P output of the field effect transistors.

2. The logic circuit of claim 1 , wherein the logic circuit comprises a logic gate selected from the group consisting of one-C PP vertical transport inverter, two-C PP double width vertical transport inverter, two-C PP NOR vertical transport logic gate, and three-C PP NAND vertical transport logic gate, and combinations thereof, wherein:
the two-C PP double width vertical transport inverter provides a function equivalent to a three-C PP inverter in which the field effect transistors are planar; and
wherein the three-C PP NAND vertical transport logic gate provides a function equivalent to a five-C PP logic gate in which the field effect transistors are planar.

3. The logic circuit of claim 1 , wherein Circuit Level M 1 is located vertically above a Circuit Level M 0 and below Circuit Level M 2 , wherein Circuit Level M 0 comprises conductive elements connected to contacts in trenches in top source/drain regions and contacts in trenches in bottom source/drain regions.

4. The logic circuit of claim 1 , wherein one or more via elements are vertically located between, and electrically connected, to conductive elements in both Circuit Levels M 1 and M 2 .

5. The logic circuit of claim 1 , wherein Circuit Level M 1 comprises one or all of the following components: a conductive element electrically connected in the same level to ground and power, a conductive element electrically connected in the same level to a voltage output, and a conductive element electrically connected in the same level to a voltage input to the gate.

6. The logic circuit of claim 1 , further comprising a Circuit Level M 0 comprising a vertical portion of the logic circuit above Level FET and below Circuit Level M 1 , which Circuit Level M 0 comprises a horizontal plane through at least one of the conductive elements in the level, which conductive elements in Circuit Level M 0 comprise at least one, or all, of the following components: a conductive element indirectly connected, at a higher level, to ground, power, input, output, and a conductive bridge from the N output to P output.

7. The logic circuit of claim 6 , wherein Level FET is located vertically below Circuit Level M 0 , and wherein at least one conductive via is vertically located between Level FET and Circuit Level M 0 .

8. The logic circuit of claim 1 , wherein Level FET comprises at least one horizontal plane through the fins or gates of the vertical transport field effect transistors.

9. The logic circuit of claim 1 , wherein the vertical transport in the logic circuit is, from a bottom S/D region, in order from lower to upper levels, as follows: a contact with a bottom S/D region to, through a via element, a conductive element in Circuit Level M 0 and, through another via element, to a conductive element in Circuit Level M 1 and thereafter to ground and power.

10. The logic circuit of claim 1 , wherein the vertical transport in the logic circuit is, in order from the top S/D regions, as follows: a conductive element in Circuit Level M 0 and, through a via element, a conductive element in Circuit Level M 1 and, through another via element, a conductive element bridging and connecting N output to P output.

11. The logic circuit of claim 1 , comprising a vertical transport NOR logic gate that comprises first and second gate structures and, at Circuit level M 1 , two voltage inputs, respectively, to the first and second gate structures.

12. The logic circuit of claim 1 , comprising a NAND logic gate having three separate gate structures and a plurality of VTFETs.

Assignees

• IBM

Inventors

• Anderson Brent A
• Chu Albert M
• Nowak Edward J

Classifications

• H10W20/43

  Layouts of interconnections · CPC title

• H10W20/42

  Vias, e.g. via plugs · CPC title

• H10D84/837

  comprising vertical IGFETs · CPC title

• H10D84/85

  Complementary IGFETs, e.g. CMOS · CPC title

• H01L23/5226

  Electricity · mapped topic