A method of masking a feature of a substrate using a fixture includes removably coupling a fixture to a first side of the feature of the substrate, the fixture including walls configured to abut sides of the feature and extend beyond a top surface of the feature when the fixture is removably coupled to the first side. The method further includes applying a masking material to the top surface of the feature. The method further includes removably coupling the fixture to a second side of the feature, the second side opposing the first side, the walls of the fixture configured to abut the sides of the feature and extend beyond a bottom surface of the feature when the fixture is removably coupled to the second side. The method further includes applying the masking material to the bottom surface of the feature while the fixture is removably coupled.