According to one exemplary embodiment, a bipolar transistor comprises a base having a top surface. The bipolar transistor further comprises a base oxide layer situated on top surface of the base. The bipolar transistor further comprises a sacrificial post situated on base oxide layer. The bipolar transistor further comprises a conformal layer situated over the sacrificial post and top surface of the base, where the conformal layer has a density greater than a density of base oxide layer. The conformal layer may be, for example, HDPCVD oxide. According to this exemplary embodiment, the bipolar transistor further comprises a sacrificial planarizing layer situated over the conformal layer. The sacrificial planarizing layer has a first thickness in a first region between first and second link spacers and a second thickness in a second region outside of first and second link spacers, where the second thickness is generally greater than the first thickness.