Atomic layer processing for doping of SiGe

• Published in: Thin solid films Vol. 508; no. 1; pp. 279 - 283
• Main Authors: Tillack, Bernd, Yamamoto, Yuji, Bolze, Detlef, Heinemann, Bernd, Rücker, Holger, Knoll, Dieter, Murota, Junichi, Mehr, Wolfgang
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Lausanne Elsevier B.V 05.06.2006; Elsevier Science
• Subjects: Applied sciences; Atomic layer doping; Electronics; Epitaxy; Exact sciences and technology; HBT; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; SiGe; Transistors; SiGe; HBT; Epitaxy; Atomic layer doping; High performance; Atomic layer method; Voltage current curve; Ge-Si alloys; Experimental study; Doping profile; Chemical vapor deposition; Phosphorus addition; Inorganic compound; Adsorption; Sheet resistivity; Low pressure; Boron addition; Heterojunction bipolar transistors; Gallium selenides
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2005.08.408

Atomic layer processing has been demonstrated for doping of SiGe during Reduced Pressure Chemical Vapour Deposition (RPCVD) in a commercial single wafer reactor. Atomic level control of dose and location has been obtained for B doping using B 2H 6 and for P doping using PH 3. The main idea of atomic layer processing is the separation of adsorption of the reactant gases from the deposition process. By this way, self-limitation has been shown for P doping. By lowering the temperature for B 2H 6 exposure (100 °C), the non-self-limiting character of the B doping process can be changed to self-limitation. By this manner, very shallow doping profiles with low sheet resistance have been obtained, capable for future ultra-shallow junction applications. P atomic layer doping is shown to be suitable for the creation of steep and narrow doping profiles suitable for high-performance pnp Heterojunction Bipolar Transistors (HBTs). This result, together with the already demonstrated usage of B atomic layer doping for npn HBTs, demonstrates the capability of the atomic layer processing approach for future devices with critical requirements for dopant dose and location control.