Place-holding library elements for defining routing paths

A stopper cell for use in combination with a plurality of additional library cells to form a netlist description of an integrated circuit formed on and within a semiconductor layer, the stopper cell defined by code comprising:

• a. data specifying a first conductor adapted to convey a first power-supply voltage through the stopper cell from a first adjacent one of the additional library cells to a second adjacent one of the additional library cells;
• b. data specifying a second conductor adapted to convey a second power-supply voltage through the stopper cell from the first adjacent library cell to the second adjacent library cell;
• c. data specifying an input port defined between the first and second conductors and electrically isolated from the first and second conductors and from a portion of the semiconductor layer beneath the stopper cell;
• d. data specifying an output port defined between the first and second conductors and electrically isolated from the first and second conductors and from the portion of the semiconductor layer beneath the stopper cell;
• and
• e. data specifying a third conductor connected between the input port and the output port.

An integrated circuit comprising:

• a. a semiconductor layer;
• b. a first logic cell defined within a bounding box in a plane parallel to the semiconductor layer, the first logic cell including:
• i. an input port located within the bounding box;
• ii. an output port located within the bounding box;
• and
• iii. a conductive strip connected between the input port and the output port;
• iv. an insulating layer disposed over the semiconductor layer and separating the semiconductor layer within the first logic cell from each of the input port, the output port, and the conductive strip;
• and
• v. a conductive segment extending from the output port to an edge of the bounding box;
• and
• c. a second logic cell including an electrical contact extending between the semiconductor layer and the one conductive segment.

A method of routing functional blocks of an integrated circuit, the method comprising:

• a. preparing a netlist that includes data structures defining each functional block, the data structure including data representing input and output ports for each functional block;
• b. associating a place-holding cell with each at least one of the input and output ports of one of the functional blocks, the place-holding cell including a first port defined as connected to the at least one port;
• c. adding the place-holding cell to the netlist;
• d. grouping the place-holding cell with the one functional block;
• e. defining routing paths interconnecting the functional blocks, wherein one of the routing paths extends through the place-holding cell to the at least one of the input and output ports.