One embodiment of the present invention provides a system that approximates a shape of an object with a closed Bezier curve. Such consumers are provided with an opportunity to purchase or otherwise learn about such complementary products andor services, and secondary merchants are provided with the opportunity to sell or market such complimentary products andor services in a way that would not jeopardize the first merchant’s sale, and indeed, in a way that might provide a benefit to the first merchant. The method include selectively etching the doped oxide layer with an etchant comprising DI:HF and an acid to provide a pH of the etchant such that the etchant includes a selectivity of phosphosilicate glass to nitride of greater than 250:1, and an etch rate through PSG of greater than 9,000 \u212bminute.