Method and apparatus for distributing an optical clock in an integrated circuit

A method for optically clocking an integrated circuit in a semiconductor having at least front and back sides, the method comprising the steps of:

• receiving master laser pulses having a master clock frequency through the back side of the semiconductor into a first photo detector disposed in the semiconductor;
• converting a current generated in the first photo detector in response to the master laser pulses into a clock signal;
• and
• clocking a first area of the integrated circuit disposed in the semiconductor.

An optical clock distribution network, comprising:

• a first photo detector disposed in a first semiconductor having at least front and back sides;
• a mode locked laser configured to emit master laser pulses at a master clock frequency through the back side of the first semiconductor into the first photo detector;
• and
• a first current to voltage converter coupled to the first photo detector, the first current to voltage converter generating a first clock signal configured to clock a first area of an integrated circuit disposed in the first semiconductor.

An optical clock distribution network, comprising:

• a first photo detector disposed in a first semiconductor having at least front and back sides;
• a second photo detector disposed in the first semiconductor;
• a laser configured to emit master laser pulses at a master clock frequency through the back side of the first semiconductor into the first and second photo detectors;
• a first current to voltage converter coupled to the first photo detector, the first current to voltage converter generating a first clock signal configured to clock a first area of an integrated circuit disposed in the first semiconductor;
• a second current to voltage converter coupled to the second photo detector, the second current to voltage converter generating a second clock signal configured to clock a second area of the integrated circuit in the first semiconductor, the first and second clock signals having the master clock frequency;
• and
• an optics element coupled between the laser and the first and second photo detectors, the optics element configured to split the master laser pulses into first and second split laser pulses focused through the back side of the first semiconductor into the first and second photo detectors respectively.

An optical clock distribution network, comprising:

• a first photo detector disposed in a first semiconductor having at least front and back sides;
• a second photo detector disposed in a second semiconductor having at least front and back sides;
• a laser configured to emit master laser pulses at a master clock frequency through the back side of the first semiconductor into the first photo detector and through the back side of the second semiconductor into the second photo detector;
• a first current to voltage converter coupled to the first photo detector, the first current to voltage converter generating a first clock signal configured to clock a first area of an integrated circuit disposed in the first semiconductor;
• a second current to voltage converter coupled to the second photo detector, the second current to voltage converter generating a second clock signal configured to clock a second area of an integrated circuit in the second semiconductor, the first and second clock signals having the master clock frequency;
• and
• an optics element coupled between the laser and the first and second photo detectors, the optics element configured to split the master laser pulses into first and second split laser pulses, the first split laser pulses focused through the back side of the first semiconductor into the first photo detector, the second split laser pulses focused through the back side of the second semiconductor into the second photo detector.