Si/SiGe-Heterobipolartransistoren fuer integrierte Schaltungen hoechster Geschwindigkeit Abschlussbericht

Abstract

The first prototype of a self-adjusting Si/SiGe heterobipolar transistor (HBT) suited for integrated circuits was developed within the framework of this joint project. The HBT is characterized by implanted contacts and by an exalted spacer oxide on the emitter mesa edges. Guides are connected by means of a well-planarizing auxiliary polyimide layer. The entire chip is covered with passivating SiO_2. Two-layer metallization can be applied due to low-stepped individual sections. The relatively great base-collector capacity at the present stage of development is due to the existing simple mask technique as well as to preliminary base contacting in an additional contact zone. The low collector doping of 3 x 10"1"6/cm"3 which is selected for integrated circuits reduces the critical frequency of the individual transistor and adds to problems which result from e.g. line and valence band offsets. The maximum HBT transit frequency has been amounting to 40 GHz. Sputtered WSi_2 films on SiO_2 are used for implementation of integrated-circuit resistances. After circuit simulations of a multiplexer IC, an MUX layout was developed, and the first process steps were made. (orig.)Available from TIB Hannover: F94B981+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman