Deep Diffusion Doping of Macroporous Silicon

• Published in: Physica status solidi. A, Applied research Vol. 182; no. 1; pp. 145 - 150
• Main Authors: Astrova, E.V., Voronkov, V.B., Grekhov, I.V., Nashchekin, A.V., Tkachencko, A.G.
• Format: Journal Article
• Language: English
• Published: Berlin WILEY-VCH Verlag Berlin GmbH 01-11-2000; WILEY‐VCH Verlag Berlin GmbH
• ISSN: 0031-8965; 1521-396X
• DOI: 10.1002/1521-396X(200011)182:1<145::AID-PSSA145>3.0.CO;2-#

We studied the diffusion of boron and phosphorus impurities into the walls of macroporous silicon with a regular pattern of deep cylindrical pores. The layers obtained had a depth of ∼150–250 μm, were quasiuniformly doped, and were characterized by a flat diffusion front. Their electric parameters were very similar to those of doped nonporous crystal. It was demonstrated that deep diffusion of phosphorus may be used to produce n–n+ structures and this technique is compatible with the conventional processes of silicon device fabrication.