Abstract: An apparatus and method for efficiently creating layout for memory bit cells are described. In various implementations, a memory bit cell uses pairs of transistors that are vertically stacked gate all around (GAA) transistors with gate terminals forming a T-shape with respect to one another and a single gate contact that overlaps only one active layer of the two active layers of the pair. Transistors of such a pair of field effect transistors (FETs) are referred to as TFETs. With respect to one another, the active layers of TFETs use opposite doping polarities and conduct current in an orthogonal direction. A non-overlapping distance between top and bottom active layers of a pair of TFETs is at least a width of a drain/source contact. The orthogonal current flow of the top and bottom active layers simplifies local connections that reduces the resistance and capacitance of the signal routes.

Abstract: A system and method for efficiently creating layout for memory bit cells are described. In various implementations, cells of a library use Cross field effect transistors (FETs) that include vertically stacked gate all around (GAA) transistors with conducting channels oriented in an orthogonal direction between them. The channels of the vertically stacked transistors use opposite doping polarities. A first category of cells includes devices where each of the two devices in a particular vertical stack receive a same input signal. The second category of cells includes devices where the two devices in a particular vertical stack receive different input signals. The cells of the second category have a larger height dimension than the cells of the first category.

Abstract: An apparatus and method for efficiently routing power signals across a semiconductor die. In various implementations, an integrated circuit uses Cross field effect transistors (FETs) with a first device, such as n-type device, having a first channel oriented in a first direction and connected to a ground reference voltage level provided by a backside metal layer. The Cross FETs also use a second device, such as the p-type device, having a second channel oriented in a second direction orthogonal to the first direction and connected to a power supply reference voltage level provided by a frontside metal layer. A micro through silicon via (TSV) traverses the silicon substrate layer in order to be placed between the backside metal layer and the source region of an n-type device. The power connections reduce on-die area, reduces semiconductor fabrication complexity, which improves wafer yield, and reduces voltage droop, which increases performance.

Abstract: An apparatus and method for efficiently routing power signals across a semiconductor die. In various implementations, an integrated circuit includes a micro through silicon via (TSV) that traverses a silicon substrate layer to a backside metal layer. The integrated circuit also includes power switches. The integrated circuit routes a power supply signal from the output of a power switch to a frontside power rail using the micro TSV and the backside metal layer. The integrated circuit also routes the power supply signal from the output of the power switch to the frontside power rail using a frontside metal layer. Therefore, the frontside metal layer and the backside metal layer provide power connection redundancy that increases charge sharing, improves wafer yield, reduces voltage droop, and reduces on-die area. In addition, the process routes a ground reference voltage level using both a frontside power rail and a backside power rail.

Abstract: An apparatus and method for efficiently routing power signals across a semiconductor die. In various implementations, an integrated circuit includes, at a first node that receives a power supply reference, a first micro through silicon via (TSV) that traverses through a silicon substrate layer to a backside metal layer. The integrated circuit includes, at a second node that receives the power supply reference, a second micro TSV that physically contacts at least one source region. The integrated circuit includes a first power rail that connects the first micro TSV to the second micro TSV. This power rail replaces contacts between the micro TSVs and a second power rail such as the frontside metal zero (M0) layer. Each of the first power rail, the second power rail, and the backside metal layer provides power connection redundancy that increases charge sharing, improves wafer yield, and reduces voltage droop.

Abstract: An apparatus and method for efficiently routing power signals across semiconductor dies. A semiconductor fabrication process (or process) places a first semiconductor die in an integrated circuit and stacks a second semiconductor die vertically adjacent to the first semiconductor die. The process forms multiple backside metal layers vertically adjacent to a backside of a silicon substrate of the second semiconductor die. The process forms a first backside metal layer that includes at least a first power route that forms a rectangle within the first backside metal layer. The process forms a second backside metal layer that includes at least a second power rail that forms an L-shape within the second backside metal layer. The process connects one or more corners of the rectangle of the first power rail to a corresponding corner of a separate power rail of the second backside metal layer that forms an L-shape.

Abstract: An apparatus and method for efficiently increasing semiconductor chip functionality in a particular area. A semiconductor fabrication process (or process) grows a silicon substrate layer, and forms multiple p-type and n-type transistors along a front side surface of the silicon substrate layer. The process flips the silicon substrate layer and removes silicon substrate leaving a particular thickness of the silicon substrate layer. The process forms multiple p-type and n-type transistors along the back side surface of the silicon substrate layer, and forms metal layers that connect terminals of the transistors formed along the back side surface to particular signals. The process forms through silicon vias (TSVs) that traverse through the silicon substrate layer. The process again flips the silicon substrate layer, and forms metal layers that connect terminals of the transistors formed along the front side surface to particular signals.

Abstract: A system and method for efficiently creating layout for memory bit cells are described. In various implementations, a memory bit cell uses Cross field effect transistors (FETs) that include vertically stacked gate all around (GAA) transistors with conducting channels oriented in an orthogonal direction between them. The channels of the vertically stacked transistors use opposite doping polarities. The memory bit cell includes one of a read bit line and a write word line routed in no other metal layer other than a local interconnect layer. In addition, a six transistor (6T) random access data storage of the given memory bit cell consumes a planar area above a silicon substrate of four transistors.

Abstract: A system and method for efficiently creating layout for memory bit cells are described. In various implementations, cells of a library use Cross field effect transistors (FETs) that include vertically stacked gate all around (GAA) transistors with conducting channels oriented in an orthogonal direction between them. The channels of the vertically stacked transistors use opposite doping polarities. A first category of cells includes devices where each of the two devices in a particular vertical stack receive a same input signal. The second category of cells includes devices where the two devices in a particular vertical stack receive different input signals. The cells of the second category have a larger height dimension than the cells of the first category.

Abstract: A system and method for efficiently creating layout for memory bit cells are described. In various implementations, cells of a library use Cross field effect transistors (FETs) that include vertically stacked gate all around (GAA) transistors with conducting channels oriented in an orthogonal direction between them. The channels of the vertically stacked transistors use opposite doping polarities. One or more of these cells use a dual polarity local interconnect power connection to receive a voltage reference level from a backside bus. For example, a power supply reference voltage level is received by a p-type device from a backside bus where the connection traverses both a p-type local interconnect layer and an n-type local interconnect layer.

Abstract: A system and method for efficiently creating layout for memory bit cells are described. In various implementations, a memory bit cell uses Cross field effect transistors (FETs) that include vertically stacked gate all around (GAA) transistors with conducting channels oriented in an orthogonal direction between them. The channels of the vertically stacked transistors use opposite doping polarities. The memory bit cell includes one of a read bit line and a write word line routed in no other metal layer other than a local interconnect layer. In addition, a six transistor (6T) random access data storage of the given memory bit cell consumes a planar area above a silicon substrate of four transistors.

Abstract: A layout for a 6T SRAM cell array is disclosed. The layout doubles the number of bits per bit cell in the array by implementing dual pairs of bitlines spanning bit cell columns in the array. Alternating connections (e.g., alternating vias) may be provided for wordline access to the bitlines in the layout. Alternating the connections may reduce RC delay in the layout.

Abstract: A system and method for efficiently creating layout for memory bit cells are described. In various implementations, cells of a library use Cross field effect transistors (FETs) that include vertically stacked gate all around (GAA) transistors with conducting channels oriented in an orthogonal direction between them. The channels of the vertically stacked transistors use opposite doping polarities. One or more of these cells use a dual polarity local interconnect power connection to receive a voltage reference level from a backside bus. For example, a power supply reference voltage level is received by a p-type device from a backside bus where the connection traverses both a p-type local interconnect layer and an n-type local interconnect layer.

Abstract: A system and method for creating layout for standard cells are described. In various implementations, a standard cell uses Cross field effect transistors (FETs) that include vertically stacked gate all around (GAA) transistors with conducting channels oriented in an orthogonal direction between them. The direction of current flow of the top GAA transistor is orthogonal to the direction of current flow of the bottom GAA transistor. The channels of the vertically stacked transistors use opposite doping polarities. The orthogonal orientation allows both the top and bottom GAA transistors to have the maximum mobility for their respective carriers based on their orientation. The Cross FETs utilize a single metal layer and a single via layer for connections between the top and bottom GAA transistors.

Abstract: A system and method for efficiently creating layout for memory bit cells are described. In various implementations, cells of a library use Cross field effect transistors (FETs) that include vertically stacked gate all around (GAA) transistors with conducting channels oriented in an orthogonal direction between them. The channels of the vertically stacked transistors use opposite doping polarities. A first category of cells includes devices where each of the two devices in a particular vertical stack receive a same input signal. The second category of cells includes devices where the two devices in a particular vertical stack receive different input signals. The cells of the second category have a larger height dimension than the cells of the first category.

Abstract: A system and method for efficiently creating layout for memory bit cells are described. In various implementations, a memory bit cell uses Cross field effect transistors (FETs) that include vertically stacked gate all around (GAA) transistors with conducting channels oriented in an orthogonal direction between them. The channels of the vertically stacked transistors use opposite doping polarities. The memory bit cell includes one of a read bit line and a write word line routed in no other metal layer other than a local interconnect layer. In addition, a six transistor (6T) random access data storage of the given memory bit cell consumes a planar area above a silicon substrate of four transistors.

Abstract: A system and method for creating chip layout are described. In various implementations, a standard cell uses unidirectional tracks for power connections and signal routing. A single track of the metal one layer that uses a minimum width of the metal one layer is placed within a pitch of a single metal gate. The single track of the metal one layer provides a power supply reference voltage level or ground reference voltage level. This placement of the single track provides a metal one power post contacted gate pitch (CPP) of 1 CPP. To further reduce voltage droop, a standard cell uses dual height and half the width of a single height cell along with placing power posts with 1 CPP. The placement of the multiple power rails of the dual height cell allows alignment of the power rails with power rails of other standard cells.

Abstract: A layout for a 6T SRAM cell is disclosed. The cell layout takes a conventional 6T SRAM cell layout and restructures the layout into a more square cell layout with a single p-channel and a single n-channel across the width of the cell. Restructuring the cell layout reduces the height of wordlines and allows dual wordlines to be placed in the cell to reduce wordline resistance in the cell. Dual pairs of bitlines may also be placed in separate metal layers in the cell layout to reduce bitline resistance.

Abstract: A system and method for laying out power grid connections for standard cells are described. In various implementations, gate metal is placed over non-planar vertical conducting structures, which are used to form non-planar devices (transistors). Gate contacts connect gate metal to gate extension metal (GEM) above the gate metal. GEM is placed above the gate metal and makes a connection with gate metal through the one or more gate contacts. Gate extension contacts are formed on the GEM above the active regions. Similar to gate contacts, gate extension contacts are formed with a less complex fabrication process than using a self-aligned contacts process. Gate extension contacts connect GEM to an interconnect layer such as a metal zero layer. Gate extension contacts are aligned vertically with one of the non-planar vertical conducting structures. Therefore, in an implementation, one or more gate extension contacts are located above the active region.

Abstract: A system and method for laying out power grid connections for standard cells are described. In various embodiments, a standard cell uses unidirectional tracks for each of the multiple power vertical metal 3 layer tracks and power horizontal metal 2 tracks. One or more of the multiple vertical metal 3 layer posts are routed with a minimum length based on a pitch of power horizontal metal 2 layer straps. One or more vertical metal 1 posts used for a power connection or a ground connection are routed from a top to a bottom of an active region permitting multiple locations to be used for connections to one of the multiple power horizontal metal 2 layer straps. Two or more power horizontal metal 2 layer straps are placed within a power metal 2 layer track without being connected to one another.