{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T13:13:20Z","timestamp":1768742000224,"version":"3.49.0"},"reference-count":35,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2012,4,26]],"date-time":"2012-04-26T00:00:00Z","timestamp":1335398400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>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 \u22121 V bias. Under a 7.5 V\/\u00b5m E-field, GeSi alloys with 0.6% Si content demonstrate very strong electro-absorption with an estimated effective \u2206\u03b1\/\u03b1 around 3.5 at 1,590 nm. We compared measured \u2206\u03b1\/\u03b1 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.<\/jats:p>","DOI":"10.3390\/mi3020345","type":"journal-article","created":{"date-parts":[[2012,4,26]],"date-time":"2012-04-26T11:04:10Z","timestamp":1335438250000},"page":"345-363","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Strong Electro-Absorption in GeSi Epitaxy on Silicon-on-Insulator (SOI)"],"prefix":"10.3390","volume":"3","author":[{"given":"Ying","family":"Luo","sequence":"first","affiliation":[{"name":"Oracle Labs, Oracle, 9515 Towne Centre Drive, San Diego, CA 92121, USA"}]},{"given":"Xuezhe","family":"Zheng","sequence":"additional","affiliation":[{"name":"Oracle Labs, Oracle, 9515 Towne Centre Drive, San Diego, CA 92121, USA"}]},{"given":"Guoliang","family":"Li","sequence":"additional","affiliation":[{"name":"Oracle Labs, Oracle, 9515 Towne Centre Drive, San Diego, CA 92121, USA"}]},{"given":"Ivan","family":"Shubin","sequence":"additional","affiliation":[{"name":"Oracle Labs, Oracle, 9515 Towne Centre Drive, San Diego, CA 92121, USA"}]},{"given":"Hiren","family":"Thacker","sequence":"additional","affiliation":[{"name":"Oracle Labs, Oracle, 9515 Towne Centre Drive, San Diego, CA 92121, USA"}]},{"given":"Jin","family":"Yao","sequence":"additional","affiliation":[{"name":"Oracle Labs, Oracle, 9515 Towne Centre Drive, San Diego, CA 92121, USA"}]},{"given":"Jin-Hyoung","family":"Lee","sequence":"additional","affiliation":[{"name":"Oracle Labs, Oracle, 9515 Towne Centre Drive, San Diego, CA 92121, USA"}]},{"given":"Dazeng","family":"Feng","sequence":"additional","affiliation":[{"name":"Kotura Inc., 2630 Corporate Place, Monterey Park, CA 91754, USA"}]},{"given":"Joan","family":"Fong","sequence":"additional","affiliation":[{"name":"Kotura Inc., 2630 Corporate Place, Monterey Park, CA 91754, USA"}]},{"given":"Cheng-Chih","family":"Kung","sequence":"additional","affiliation":[{"name":"Kotura Inc., 2630 Corporate Place, Monterey Park, CA 91754, USA"}]},{"given":"Shirong","family":"Liao","sequence":"additional","affiliation":[{"name":"Kotura Inc., 2630 Corporate Place, Monterey Park, CA 91754, USA"}]},{"given":"Roshanak","family":"Shafiiha","sequence":"additional","affiliation":[{"name":"Kotura Inc., 2630 Corporate Place, Monterey Park, CA 91754, USA"}]},{"given":"Mehdi","family":"Asghari","sequence":"additional","affiliation":[{"name":"Kotura Inc., 2630 Corporate Place, Monterey Park, CA 91754, USA"}]},{"given":"Kannan","family":"Raj","sequence":"additional","affiliation":[{"name":"Oracle Labs, Oracle, 9515 Towne Centre Drive, San Diego, CA 92121, USA"}]},{"given":"Ashok V.","family":"Krishnamoorthy","sequence":"additional","affiliation":[{"name":"Oracle Labs, Oracle, 9515 Towne Centre Drive, San Diego, CA 92121, USA"}]},{"given":"John E.","family":"Cunningham","sequence":"additional","affiliation":[{"name":"Oracle Labs, Oracle, 9515 Towne Centre Drive, San Diego, CA 92121, USA"}]}],"member":"1968","published-online":{"date-parts":[[2012,4,26]]},"reference":[{"key":"ref_1","unstructured":"Pavesi, L., and Lockwood, D.J. 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