Fabrication and characterisation of SiGe based in-plane-gate transistors

• Published in: Microelectronic engineering Vol. 35; no. 1-4; pp. 301 - 304
• Main Authors: Köster, T., Stein, J., Hadam, B., Gondermann, J., Spangenberg, B., Roskos, H.G., Kurz, H., Holzmann, M., Riedinger, M., Abstreiter, G.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.1997
• ISSN: 0167-9317; 1873-5568
• DOI: 10.1016/S0167-9317(96)00132-3

We present an in-situ technology for fabrication of barrier structures in modulation-doped SiSiGe in-plane-gate (IPG) transistors. A special multilayer-resist system is developed for pattern transfer by electron-beam lithography (EBL) and anisotropic SF6O2 dry etching. Barriers are realized by etch-trenches cutting the two dimensional electron gas (2DEG). The trenches are filled up with a low temperature remote plasma enhanced chemical vapour deposition (RPECVD) of silicondioxide (SiO2). Dry-etching and passivation are done in-situ to avoid contamination. IPG transistors with different geometric dimensions have been fabricated and electrically characterised. Transistor operation is demonstrated up to T=77 K. The breakdown voltage and the depletion length of the devices are estimated. The obtained data indicate the advantage of the presented in-situ technology in comparison to other fabrication techniques.