Abstract: Techniques are provided for making asymmetric contacts to improve the performance of thin film transistors (TFT) structures. The asymmetry may be with respect to the area of contact interface with the semiconductor region and/or the depth to which the contacts extend into the semiconductor region. According to some embodiments, the TFT structures are used in memory structures arranged in a two-dimensional array within one or more interconnect layers and stacked in a vertical direction such that multiple tiers of memory structure arrays are formed within the interconnect region. Any of the given TFT structures may include asymmetric contacts, such as two contacts that each have a different contact area to a semiconductor region, and/or that extend to different depths within the semiconductor region. The degree of asymmetry may be tuned during fabrication to modulate certain transistor parameters such as, for example, leakage, capacitance, gate control, channel length, or contact resistance.

Abstract: This application describes apparatuses and methods for musculoskeletal tissue engineering. Specifically, graft collar and scaffold apparatuses are provided for promoting fixation of musculoskeletal soft tissue to bone. This application provides for graft collars comprising biopolymer mesh and/or polymer-fiber mesh for fixing tendon to bone. In one aspect, the graft collar comprises more than one region, wherein the regions can comprise different materials configured to promote integration of and the regeneration of the interfacial region between tendon and bone. This application also provides for scaffold apparatuses and methods for fixing musculoskeletal soft tissue to bone. The scaffold apparatus is multiphasic, preferably triphasic, and each phase is configured promote growth and proliferation of a different cell and its associated tissue. In one aspect, the scaffold apparatus is triphasic, with phases comprising materials to promote growth and proliferation of fibroblasts, chondroblasts, and osteoblasts.