Photronics can't mask its main business: photomasks. The company makes high-precision quartz photomasks, a key tool in the construction of semiconductors and flat-panel displays (FPDs). Photomasks carry microscopic images of electronic circuits and are used as stencils to transfer circuit patterns onto semiconductor wafers during the manufacture of integrated circuits and FPDs. Photronics also provides related services, including maintenance for etching systems, as well as research and consulting in techniques for wafer cleaning and etching. Samsung Electronics accounts for about 19% of revenues. Photronics gets around 60% of its sales from customers in Asia.