A method of manufacturing a radio frequency bipolar transistor includes fabricating a structure including a substrate having a main surface, a collector formed in the substrate, a monocrystalline base and a cavity. The collector faces the monocrystalline base in a first direction perpendicular to the main surface and the monocrystalline base faces the cavity in the first direction. A spacer layer is formed in the cavity and the spacer layer is contacting the monocrystalline base and extending in the first direction. An emitter is formed by selective epitaxial growing doped semiconductor material from a first region of the monocrystalline base wherein during the selective epitaxial growing a first sticking coefficient on the spacer layer is zero or a factor 1/10 or less of a second sticking coefficient on the monocrystalline base.

The present disclosure provides a semiconductor processing apparatus according to one embodiment. The semiconductor processing apparatus includes a chamber; a base station located in the chamber for supporting a semiconductor substrate; a preheating assembly surrounding the base station; a first heating element fixed relative to the base station and configured to direct heat to the semiconductor substrate; and a second heating element moveable relative to the base station and operable to direct heat to a portion of the semiconductor substrate.

A method includes forming a first masking layer over a substrate, the first masking layer including a first mask line and a second mask line, heating respective top surfaces of the first mask line and the second mask line with polarized light, and forming a second masking layer over the first masking layer with an area selective deposition process. The second masking layer is thinner over a sidewall of the first mask line than over a top surface of the first mask line.