On the mechanisms limiting mobility in InP/InGaAs buried channel nMISFETs

• Published in: Microelectronic engineering 2011-07, Vol.88 (7), p.1076-1078
• Main Authors: Urabe, Y., Yasuda, T., Ishii, H., Itatani, T., Miyata, N., Yamada, H., Fukuhara, N., Hata, M., Takenaka, M., Takagi, S.
• Format: Article
• Language: English
• Subjects: Al 2O 3; Applied sciences; Barrier layers; Buried channel; Channels; Condensed matter: structure, mechanical and thermal properties; Constraining; Diffusion in nanoscale solids; Diffusion in solids; Electronics; Exact sciences and technology; Fractures; Indium gallium arsenides; Indium phosphides; InGaAs; InP; Inversions; Management information systems; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; MISFET; Mobility; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Transistors; Transport properties of condensed matter (nonelectronic)
• ISSN: 0167-9317; 1873-5568
• DOI: 10.1016/j.mee.2011.03.039

Device structure of the buried-channel nMISFETs (left) and their channel mobility characteristics (right) [Display omitted] ► High peak mobility has been achieved using the InP/InGaAs buried-channel structure. ► Mobility degradation by the carrier spillover effect has been clearly observed. ► Remote scattering limits the barrier thickness scaling. MISFETs incorporating the InP/InGaAs buried channel showed a high peak mobility of 5500 cm 2/V s. Spillover of the inversion carriers from the buried channel to the MIS interface on the InP barrier layer caused drastic mobility degradation as the carrier concentration was increased. The spillover was evidenced by observing a negative transconductance and a kink in split capacitance–voltage curves. Remote scattering by the trapped charges at the MIS interface also reduced the mobility when the InP barrier layer was as thin as 2 nm.