Material growth of SiGe quantum structures


The effect of carrier confinement in quantum structure will arise several interesting physical phenomena such as two-dimensional electronic gases (2DEGs). Among various semiconductor materials, Si-based quantum structures are of particular interest. The ubiquitous characteristics of SiGe quantum structures are in potential application in novel nanoelectronics, photonics and spintronics. In this project, we focus on the material growth of SiGe quantum well. An un-doped SiGe/strained Si/SiGe quantum well was fabricated on p-type Si at 550 ℃ by hot-wall ultrahigh vacuum chemical vapor deposition. In 2012, in collaboration with Nobel Prize laureate, Phof. D. C. Tsui, we reported the undoped 2DEG Si/SiGe QW structure with the extremely high mobility of 2.0x106 cm2/Vs, a record value, at 0.3K for 15 nm Si well with a SiGe barrier layer. The quantum Hall effect characteristics are observed in the enhancement mode insulated-gate field-effect transistors (IGFETs)







Related Publications:

  1. S. -H. Huang, T. -M. Lu, S. -C. Lu, C. -H. Lee, C. W. Liu, and D. C. Tsui, “Mobility enhancement of strained Si by optimized SiGe/Si/SiGe structures,” Appl. Phys. Lett., Vol. 101, 042111, 2012. 
  2. C. -H. Lee, C. W. Liu, H. -T. Chang, and S. W. Lee, "Hexagonal SiGe Quantum Dots and Nanorings on Si(110)," J. Appl. Phys. 107, 056103, 2010APPLIED PHYSICS (SCI, EI) T. M. Lu*, C. -H. Lee, D. C. Tsui, and C. W. Liu, "Integration of complementary circuit and two-dimensional electron gas in a Si/SiGe heterostructure," Appl. Phys. Lett., Vol. 96, 253103, 2010.
  3. C.-H. Lee, Y.-Y. Shen, C. W. Liu, S. W. Lee, B.-H. Lin, and C.-H. Hsu, "SiGe nanorings by ultrahigh vacuum chemical vapor deposition," Appl. Phys. Lett., Vol. 94, 141909, 2009
  4. T. M. Lu*, D. C. Tsui, C. -H. Lee and C. W. Liu, "Observation of two-dimensional electron gas in a Si quantum well with mobility of 1.6×106 cm2/Vs," Appl. Phys. Lett., Vol. 94, 182102, 2009.
  5. C.-H. Lee, C.-Y. Yu, C. M. Lin, C.W. Liu, H. Lin, and W.-H. Chang, "Carrier gas effects on the SiGe quantum dots formation," Applied Surface Science, Vol. 254, No. 19, pp. 6257-6260, 2008.