A base-collector architecture for SiGeHBTs using low-temperature CVD epitaxy combined with chemical-mechanical polishing
2002 (English)In: Physica Scripta, ISSN 0031-8949, E-ISSN 1402-4896, Vol. T101, 64-66 p.Article in journal (Refereed) Published
A new collector technology intended for an integrated high-speed SiGe heterojunction bipolar transistor (HBT) is reported. The collector was fabricated by selective epitaxial growth (SEG) using chemical vapor deposition at 770degreesC under reduced pressure (20 torr) using SiH2Cl2 as silicon precursor and PH3 as n-type dopant source. Chemical-mechanical polishing (CMP) was applied to the overgrown SEG collector in order to achieve a smooth surface in level with the surrounding oxide. Finally, a SiGe base doped with boron was deposited using non-selective epitaxial growth (NSEG) at 650degreesC. The topography of the collector is inspected after each process step by atomic force microscopy and the topography of the completed collector/base stack indicates that this structure is promising for fabrication of the emitter window. A further advantage with the CMP procedure is the elimination of phosphorous segregation as evidenced by secondary ion mass spectroscopy of the base-collector stack.
Place, publisher, year, edition, pages
2002. Vol. T101, 64-66 p.
bipolar-transistors, leakage currents, silicon, growth
IdentifiersURN: urn:nbn:se:kth:diva-22076ISI: 000179465600017OAI: oai:DiVA.org:kth-22076DiVA: diva2:340774
QC 201005252010-08-102010-08-10Bibliographically approved