Open AccessThis article is
- freely available
Strong Electro-Absorption in GeSi Epitaxy on Silicon-on-Insulator (SOI)
Oracle Labs, Oracle, 9515 Towne Centre Drive, San Diego, CA 92121, USA
Kotura Inc., 2630 Corporate Place, Monterey Park, CA 91754, USA
* Author to whom correspondence should be addressed.
Received: 15 March 2012; in revised form: 6 April 2012 / Accepted: 18 April 2012 / Published: 26 April 2012
Abstract: We have investigated the selective epitaxial growth of GeSi bulk material on silicon-on-insulator substrates by reduced pressure chemical vapor deposition. We employed AFM, SIMS, and Hall measurements, to characterize the GeSi heteroepitaxy quality. Optimal growth conditions have been identified to achieve low defect density, low RMS roughness with high selectivity and precise control of silicon content. Fabricated vertical p-i-n diodes exhibit very low dark current density of 5 mA/cm2 at −1 V bias. Under a 7.5 V/µm E-field, GeSi alloys with 0.6% Si content demonstrate very strong electro-absorption with an estimated effective ∆α/α around 3.5 at 1,590 nm. We compared measured ∆α/α performance to that of bulk Ge. Optical modulation up to 40 GHz is observed in waveguide devices while small signal analysis indicates bandwidth is limited by device parasitics.
Keywords: electro-absorption; germanium silicon; Franz-Keldysh effect; selective epitaxial growth
Citations to this Article
Cite This Article
MDPI and ACS Style
Luo, Y.; Zheng, X.; Li, G.; Shubin, I.; Thacker, H.; Yao, J.; Lee, J.-H.; Feng, D.; Fong, J.; Kung, C.-C.; Liao, S.; Shafiiha, R.; Asghari, M.; Raj, K.; Krishnamoorthy, A.V.; Cunningham, J.E. Strong Electro-Absorption in GeSi Epitaxy on Silicon-on-Insulator (SOI). Micromachines 2012, 3, 345-363.
Luo Y, Zheng X, Li G, Shubin I, Thacker H, Yao J, Lee J-H, Feng D, Fong J, Kung C-C, Liao S, Shafiiha R, Asghari M, Raj K, Krishnamoorthy AV, Cunningham JE. Strong Electro-Absorption in GeSi Epitaxy on Silicon-on-Insulator (SOI). Micromachines. 2012; 3(2):345-363.
Luo, Ying; Zheng, Xuezhe; Li, Guoliang; Shubin, Ivan; Thacker, Hiren; Yao, Jin; Lee, Jin-Hyoung; Feng, Dazeng; Fong, Joan; Kung, Cheng-Chih; Liao, Shirong; Shafiiha, Roshanak; Asghari, Mehdi; Raj, Kannan; Krishnamoorthy, Ashok V.; Cunningham, John E. 2012. "Strong Electro-Absorption in GeSi Epitaxy on Silicon-on-Insulator (SOI)." Micromachines 3, no. 2: 345-363.