A structure with an optically active layer embedded in a Si wafer, such that the outermost epitaxial layer exposed to the CMOS processing equipment is always Si or another CMOS-compatible material such as SiO2. The fusing unit includes a replacement opening via which the roller or the lamp cartridge can be removed from or inserted into the fusing unit along an axis of the roller for replacement. As a result, the storage node capacitance of the memory cell of the SRAM is increased to improve the soft error resistance. The HUD unit includes a USB panel member having a plurality of USB receiving ports for receiving one or more of the HUD adaptors therein.