High mobility metal-oxide-semiconductor-field-effect-transistors (MOSFETs) are demonstrated on high quality epitaxial Si0.75Ge0.25 films selectively grown on Si (100) substrates. With a Si cap processed on Si0.75Ge0.25 channels, HfSiO2 high-k gate dielectrics exhibited low C-V hysteresis (<10 mV), interface trap density (7.5 × 1010), and gate leakage current (∼10-2A/cm2 at an EOT of 13.4 Å), which are comparable to gate stack on Si channels. The mobility enhancement afforded intrinsically by the Si0.75Ge0.25 channel (60%) is further increased by a Si cap (40%) process, resulting in a combined ∼100% enhancement over Si channels. The Si cap process also mitigates the low potential barrier issues of Si0.75Ge0.25 channels, which are major causes of the high off-state current of small band gap energy Si0.75Ge0.25 pMOSFETs, by improving gate control over the channel.
Bibliographical noteFunding Information:
The author would like to acknowledge the support of Front End Processes Division at SEMATECH Inc for the use of device fabrication, electrical-physical characterization, and helpful technical discussions. This work is supported by the MSIP (Ministry of Science, ICT and Future Planning), Korea, under the “IT Consilience Creative Program (NIPA-2013-H0203-13-1002) supervised by the NIPA (National IT Industry Promotion Agency). This work was supported by the Future Semiconductor Device Technology Development Program (10044735) funded By MOTIE (Ministry of Trade, Industry & Energy) and KSRC (Korea Semiconductor Research Consortium).
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Physics and Astronomy(all)