Method of manufacturing a semiconductor device including mesa bipolar transistor with edge contacts

A method of manufacturing a semiconductor device characterized in that

• 1. a silicon oxide containing insulated intermediate layer is provided on the surface of a monocrystalline silicon region and a first silicon nitride layer is provided on said intermediate layer,
• 2. a first silicon layer is provided on said first silicon nitride layer,
• 3. a silicon pattern is etched from the first silicon layer,
• 4. at least the edge of said silicon pattern is provided by thermal oxidation with an oxide layer,
• 5. the uncovered part of the first silicon nitride layer, and the subjacent intermediate layer are removed,
• 6. a depression is etched into the exposed part of the silicon region,
• 7. the uncovered oxide is removed,
• 8. the uncovered silicon is provided by thermal oxidation with a further oxide layer,
• 9. the remaining exposed parts of said first silicon nitride layer and said intermediate layer are removed,
• 10. a second highly doped silicon layer is provided on the assembly, said second silicon layer being removed by planarization and etching down to a level lying below that of the oxide present on the first silicon layer,
• 11. the exposed silicon oxide is selectively removed by etching,
• 12. the exposed parts of said first silicon nitride layer are removed and at least one connection zone is formed by doping in the underlying parts of said silicon region,
• 13. said first silicon layer is selectively etched away, said second silicon layer and said connection zone are oxidized and at least one first zone is formed by diffusion from said second silicon layer,
• 14. said first silicon nitride layer is removed, and
• 15. an electrode is provided on the surface of a second zone located within the window thus formed, which is bounded by said further oxide layer.