Abstract: There is disclosed herein a transistor having a sidewall base contact. The base region of the transistor is in a column of selectively grown epitaxial silicon isolated from adjacent structures in a field of oxide. The sidewall base contact is a layer of doped polysilicon which is embedded in the insulating material surrounding the column of epitaxial silicon. The collector contact is formed of another column of selectively grown epitaxial silicon grown over and in electrical contact with a buried layer underlying the first column of epitaxial silicon. The emitter region is implanted into the top of column doped as the base region. In one embodiment, the base contact is a buried polysilicon layer. In another embodiment, the base contact is epitaxial silicon which is grown over oxide by uncontrolled growth following controlled selective growth.