Abstract: A method and an apparatus for optically clocking an integrated circuit in a semiconductor. In one embodiment, a laser is configured to emit infrared laser pulses at a desired clock frequency. The laser pulses are separated into a plurality of split laser pulses, each of which are focused through the back side of a C4 packaged integrated circuit die into P-N junctions distributed throughout the integrated circuit die. Each P-N junction locally generates a photocurrent in response to the split laser beams. Each of the photocurrents are locally converted into voltages and thus into local clock signals, which are used to clock the local area of the integrated circuit. With the presently described optical clocking technique, the local clock signals have extremely low clock skew. The presently described technique may be employed in integrated circuits system-wide, in multi-chip modules, or in an individual integrated circuit.

Abstract: A method and an apparatus for optically clocking an integrated circuit in a semiconductor. In one embodiment, a laser is configured to emit infrared laser pulses at a desired clock frequency. The laser pulses are separated into a plurality of split laser pulses, each of which are focused through the back side of a C4 packaged integrated circuit die into P-N junctions distributed throughout the integrated circuit die. Each P-N junction locally generates a photocurrent in response to the split laser beams. Each of the photocurrents are locally converted into voltages and thus into local clock signals, which are used to clock the local area of the integrated circuit. With the presently described optical clocking technique, the local clock signals have extremely low clock skew. The presently described technique may be employed in integrated circuits system-wide, in multi-chip modules, or in an individual integrated circuit.