Structure, structure and method for providing an on-chip variable delay transmission line with fixed characteristic impedance

A method of manufacturing a semiconductor structure, comprising:

• forming a signal line;
• forming a first ground return rail and a first capacitance structure;
• forming a second ground return rail and a second capacitance structure;
• forming the first ground return rail and the first capacitance structure as a first ground return structure;
• and
• forming the second ground return rail and the second capacitance structure as a second ground return structure,
• wherein the first ground return rail is further away from the signal line than the second ground return rail,
• the first capacitance structure is closer to the signal line than the second capacitance structure,
• grounding for the signal line is selectively switched between the first ground return rail and the second ground return rail,
• the signal line, the first ground return structure, and the second ground return structure are comprised in a transmission line structure,
• the first ground return structure creates a first delay and a first characteristic impedance in the transmission line structure,
• the second ground return structure creates a second delay different from the first delay and a second characteristic impedance substantially equal to the first characteristic impedance, and
• the first ground return structure provides a higher inductance than the second ground return structure.

A method of manufacturing a semiconductor structure, comprising:

• forming a signal line;
• forming a first ground return rail and a first capacitance structure;
• and
• forming a second ground return rail and a second capacitance structure,
• wherein the first ground return rail is further away from the signal line than the second ground return rail,
• the first capacitance structure is closer to the signal line than the second capacitance structure,
• grounding for the signal line is selectively switched between the first ground return rail and the second ground return rail, and
• the first ground return rail and the first capacitance structure provide a higher inductance than the second ground return rail and the second capacitance structure.