A backlight unit for a liquid crystal display device, the backlight unit including: an light emitting diode (“LED”) light source; a light conversion layer disposed separate from the LED light source to convert light emitted from the LED light source to white light and to provide the white light to the liquid crystal panel; and a light guide panel disposed between the LED light source and the light conversion layer, wherein the light conversion layer includes a semiconductor nanocrystal and a polymer matrix, and wherein the polymer matrix includes a first polymerized polymer of a first monomer including at least two thiol (—SH) groups, each located at a terminal end of the first monomer, and a second monomer including at least two unsaturated carbon-carbon bonds, each located at a terminal end of the second monomer.