In general, in one aspect, a method includes forming a semiconductor substrate having an N+ diffusion region, a shallow trench isolation (STI) region adjacent to the N+ diffusion region, and a blocked salicide poly resistor (BSR) region over the STI region. An oxide layer is over the substrate. A nitride layer is formed over the oxide layer and is annealed. A resist layer is patterned on the annealed nitride layer, wherein the resist layer covers a portion of the BSR region. The annealed nitride layer is etched using the resist layer as a pattern. The resist layer is removed and the oxide layer is etched using the annealed nitride layer as a pattern. Germanium pre-amorphization is implanted into the substrate, wherein the oxide and the annealed nitride layers protect a portion of the BSR region from the implanting.