Layout designs of integrated circuits having backside routing tracks

An integrated circuit comprising:

• a semiconductor substrate;
• a first logic gate and a second logic gate formed with transistors having channel regions on the semiconductor substrate, a first output of the first logic gate being configured to generate a first output logic signal having a first output phase different from a first input phase of a first input logic signal at a first input of the first logic gate, and wherein the first output of the first logic gate is conductively connected to an second input of the second logic gate;
• horizontal routing tracks extending in a first direction in a first metal layer, wherein a first horizontal routing track is conductively connected to the first input of the first logic gate through a first via connector;
• and
• one or more backside routing tracks extending in the first direction in a backside metal layer, wherein a first backside routing track is conductively connected to the first output of the first logic gate through a backside via connector, and wherein the channel regions of the transistors are between the backside metal layer and the first metal layer.

A method of fabricating an integrated circuit, the method comprising:

• fabricating gate-strips extending in a second direction perpendicular to a first direction, wherein a gate-strip overlaps an active zone extending in the first direction at a first intersection and forms a gate terminal of a first transistor;
• fabricating conductive segments extending in the second direction, wherein a conductive segment overlaps the active zone at a second intersection and forms a channel connecting terminal of the first transistor, the channel connecting terminal including either a source terminal or a drain terminal;
• fabricating a horizontal routing track, extending in the first direction, in a first metal layer;
• forming a front side via connector connecting the horizontal routing track to a first one of the gate terminal or the channel connecting terminal of the first transistor;
• fabricating a backside routing track, extending in the first direction, in a backside metal layer, and wherein the backside metal layer and the first metal layer are formed at opposite sides of a semiconductor substrate;
• and
• forming a backside via connector connecting a backside routing track to a second one of the gate terminal or the channel connecting terminal of the first transistor.