A semiconductor device including a capacitor and a proximate high-voltage gate having a boron-barrier layer that ideally serves as part of both the capacitor dielectric and the (high voltage) HV gate oxide. The boron-barrier layer is preferably formed over a poly oxide layer that is in turn deposited on a substrate infused to create a neighboring wells, and N-well over which the capacitor will be formed, and P-well to be overlaid by the HV gate. The boron-barrier helps to reduce or eliminate the harmful effects of boron diffusion from the P-well during TEOS deposition of the gate oxide material.