Semiconductor device and method of manufacturing the same

1. A method of manufacturing a semiconductor device including a complementary metal oxide semiconductor (CMOS) and a bipolar junction transistor (BJT), the method comprising the steps of:

forming a gate oxide layer on a substrate in which a p-type well and an n-type well are formed;

removing the gate oxide layer on the p-type well;

forming bases made of polysilicon on the p-type well;

forming a first photosensitive layer pattern that exposes the bases on the substrate;

implanting p-type impurity ions into the bases through the first photosensitive layer pattern;

removing the first photosensitive layer pattern;

forming a second photosensitive layer pattern that exposes the p-type well and the n-type well on the bases and the substrate; and

implanting n-type impurity ions into the p-type well and the n-type well through the second photosensitive layer pattern to form an emitter and a collector of the BJT.

2. The method of claim 1 , wherein the gate electrode of the CMOS is formed when the bases are formed.

3. The method of claim 1 , wherein p-type impurity ions are implanted into the source and drain regions of a PMOS in the CMOS when the p-type impurity ions are implanted into the bases.

4. The method of claim 1 , wherein n-type impurity ions are implanted into the source and drain regions of the PMOS in the CMOS when the n-type impurity ions are implanted into the p-type well and the n-type well.

5. The method of claim 1 , further comprising the steps of:

forming silicides on the bases, the emitter, and the collector;

forming an insulating layer having contact holes that expose the silicides on the substrate; and

forming base contacts, an emitter contact, and a collector contact for filling the contact holes.