A semiconductor device includes a first and a second power rails extending in a row direction, a third power rail extending in the row direction between the first and second power rail, and a first cell arranged between the first second power rails. A cell height of the first cell in a column direction perpendicular to the row direction is equal to a pitch between the first and second power rails. The semiconductor device also includes a second cell arranged between the first and third power rails. A cell height of the second cell in the column direction is equal to a pitch between the first and third power rails. A first active region of the first cell includes a first width in the column direction greater than a second width, in the column direction, of a second active region in the second cell.

A method includes receiving a substrate having a front surface and a back surface; forming an isolation feature of a first dielectric material in the substrate, thereby defining an active region surrounded by the isolation feature; forming a gate stack on the active regions; forming a first and a second S/D feature on the fin active region; forming a front contact feature contacting the first S/D feature; thinning down the substrate from the back surface such that the isolation feature is exposed; selectively etching the active region, resulting in a trench surrounded by the isolation feature, the second S/D feature being exposed within the trench; forming, in the trench, a liner layer of a second dielectric material being different from the first dielectric material; forming a backside via feature landing on the second S/D feature within the trench; and forming a backside metal line landing on the backside via feature.

A semiconductor device (1) according to an embodiment includes: a semiconductor substrate; a first well (15) formed on the semiconductor substrate; a second well (15) formed on the semiconductor substrate; first fins (11) formed in the first well; second fins (21) formed in the second well; and a first electrode (12a) connected to each of the first and second fins. The first well and the first fins (11) have the same conductivity type, and the second well and the second fins (21) have different conductivity types.

A semiconductor device includes: a virtual power line extended in a first direction; an n-well extended in the first direction, wherein the virtual power line and the n-well are disposed in a row; a first power gate switch cell disposed in the n-well; a second power gate switch cell disposed in the n-well, wherein the first and second power gate switch cells are first type cells; and a third power gate switch cell disposed in the n-well between the first and second power gate switch cells, wherein the third power gate switch cell is a second type cell different from the first type cells.

A semiconductor structure includes an isolation structure, a source or drain region over the isolation structure, a channel layer connecting to the source or drain region, a gate structure over the isolation structure and engaging the channel layer, an isolating layer below the channel layer and the gate structure, a dielectric cap below the isolating layer, and a contact structure having a first portion and a second portion. The first portion of the contact structure extends through the isolation structure, and the second portion of the contact structure extends from the first portion of the contact structure, through the dielectric cap and the isolating layer, and to the source or drain region. The first portion of the contact structure is below the second portion and wider than the second portion.

A MOS IC logic cell includes a plurality of gate interconnects extending on tracks in a first direction. The logic cell includes intra-cell routing interconnects coupled to at least a subset of the gate interconnects. The intra-cell routing interconnects include intra-cell Mx layer interconnects on an Mx layer extending in the first direction. The Mx layer is a lowest metal layer for PG extending in the first direction. The intra-cell Mx layer interconnects extend in the first direction over at least a subset of the tracks excluding every m.sup.th track, where 2≤m<P.sub.PG and P.sub.PG is a PG grid pitch. A MOS IC may include at least one MOS IC logic cell, and may further include a first set of PG Mx layer interconnects extending in the first direction over the at least one logic cell. The first set of PG Mx layer interconnects have the pitch P.sub.PG>m*P.

A cell architecture and a method for placing a plurality of cells to form the cell architecture are provided. The cell architecture includes at least a 1.sup.st cell and a 2.sup.nd cell placed next to each other in a cell width direction, wherein the 1.sup.st cell includes a one-fin connector which is formed around a fin among a plurality of fins of the 1.sup.st cell, and connects a vertical field-effect transistor (VFET) of the 1.sup.st cell to a power rail of the 1.sup.st cell, wherein a 2.sup.nd cell includes a connector connected to a power rail of the 2.sup.nd cell, wherein the fin of the 1.sup.st cell and the connector of the 2.sup.nd cell are placed next to each other in the cell width direction in the cell architecture, and wherein the one-fin connector of the 1.sup.st cell and the connector of the 2.sup.nd cell are merged.

A semiconductor device and a method of forming the same are provided. In an embodiment, an exemplary semiconductor device includes two stacks of channel members; a source/drain feature extending between the two stacks of channel members along a direction; a source/drain contact disposed under and electrically coupled to the source/drain feature; two gate structures over and interleaved with the two stacks of channel members; a low-k spacer horizontally surrounding the source/drain contact; and a dielectric layer horizontally surrounding the low-k spacer.

An integrated circuit includes a trench power rail to reduce resistance in a power rail or avoid an increase in resistance of a power rail as a result of the metal tracks being reduced in size as the technology node size is reduced. The trench power rail is formed in isolation regions between cell circuits. A cell isolation trench in the isolation region provides additional volume in which to dispose additional metal material for forming the trench power rail to increase its cross-sectional area. The trench power rail extends through a via layer to a metal layer, including signal interconnects. The trench power rail extends in a width direction out of the cell isolation trench in the via layer to couple to trench contacts of the adjacent cell circuits without vertical interconnect accesses (vias). A high-K dielectric layer can selectively isolate the trench power rail from the cell circuits.

A semiconductor device includes a first transistor formed on a first side of a substrate. The semiconductor device includes a first power rail structure vertically disposed over the first transistor, a second power rail structure vertically disposed over the first power rail structure, and a memory portion vertically disposed over the second power rail structure. The first power rail structure, and a second power rail structure, and the memory portion are all disposed on a second side of the substrate opposite to the first side.