43. 3D IC-

♤ In electronics, a three-dimensional integrated circuit (3D IC, 3D-IC, or 3-D IC) is a chip in which two or more layers of active electronic components are integrated both vertically and horizontally into a single circuit. The semiconductor industry is pursuing this promising technology in many different forms, but it is not yet widely used; consequently, the definition is still somewhat fluid.

♤ Traditional scaling of semiconductor chips also improves signal propagation speed. However, scaling from current manufacturing and chip-design technologies has become more difficult, in part because of power-density constraints, and in part because interconnects do not become faster while transistors do 3-D integrated circuits were proposed invented to address the scaling challenge by stacking 2-D dies and connecting them in the 3rd dimension. This promises to speed up communication between layered chips, compared to planar layout.