Optoelectronic logic functions using optical bias controlled SiC multilayer devices

摘要

The purpose of this paper is the design of simple combinational optoelectronic circuit based on SiC technology, able to act simultaneously as a 4-bit binary encoder or a binary decoder in a 4-to-16 line configurations. The 4-bit binary encoder takes all the data inputs, one by one, and converts them to a single encoded output. The binary decoder decodes a binary input pattern to a decimal output code. The optoelectronic circuit is realized using a a-SiC:H double pin/pin photodetector with two front and back optical gates activated trough steady state violet background. Four red, green, blue and violet input channels impinge on the device at different bit sequences allowing 16 possible inputs. The device selects, through the violet background, one of the sixteen possible input logic signals and sends it to the output. Results show that the device acts as a reconfigurable active filter and allows optical switching and optoelectronic logic functions development. A relationship between the optical inputs and the corresponding digital output levels is established. A binary color weighted code that takes into account the specific weights assigned to each bit position establish the optoelectronic functions. A truth table of an encoder that performs 16-to-1 multiplexer (MUX) function is presented.