Optical I/O "Pins" and "Pin" Grid Arrays for MCM Inter-Layer and External Connectivity

The increased complexity of electronic circuits and reduced component sizes has resulted in large numbers of input/output (I/O) interconnections for each module layer. However, the number of electrical interconnects are sensitive to external electromagnetic interference and inter-channel electrical crosstalk. Thus, Physical Optics Corporation (POC) proposed a new optical input/output "pin" and "pin" grid array concept for two-dimensional inter-layer interconnects and system I/O. POC's concept is based on commercially developed graded index lenses, vertical cavity surface emitting lasers, holographic diffractions gratings, holographic fanout elements, and optical backplanes. The advantages of the optical "pin" concept include high data rate input/output (over 3 GHz), low loss, low signal propagation delay, high immunity to EMI, low crosstalk at high speeds, high "pin" count (200/cm2[squared] to 2500/cm2 [squared]), and low cost. In Phase I, POC will provide a feasibility demonstration of a small optical interconnect prototype based on the proposed optical "pin" concept. The Phase II research will produce a fully integrated multi-element high "pin" count prototype system for both inter-layer and external interconnects of compact packaged multichip module systems.