some embodiments as a stop region next an inter gate dielectric 146 is formed as illustrated by fig9 in this embodiment the inter gate dielectric 146 is a spun on dielectric sod applied with an overburden 148 in other embodiments it may be a different material applied with a different process e g cvd or ald the spun on dielectric may be a spun on glass such as oxide and in some embodiments the spun on dielectric may be densified by placing the substrate 102 in a furnace to drive volatile compounds from the spun on dielectric in some embodiments the liner 142 may protect other portions of the substrate 102 from film stresses developed during densification after forming the inter gate dielectric 146 the substrate 102 may be generally planarized with chemical mechanical planarization cmp as illustrated by fig1 the cmp process may remove the overburden 148 a top portion of the liner 142 and stop on or near the sacrificial masking region 124 the transition between the inter gate dielectric 146 and the liner 142 may produce a detectable phenomenon such as a change in optical properties of the substrate e g color chemical properties e g waste slurry ph or mechanical properties e g sliding friction that triggers an end to the cmp process the transition between the liner 142 and the sacrificial masking region 124 may also produce similar detectable phenomena for end pointing the process in some embodiments the cmp process stops on or near the liner 142 and does not expose the sacrificial masking.