80 nm gate-length Si/Si
 0.7
 Ge
 0.3
 n
 -MODFET with 194 GHz
 
 f
 
 max

Koester, Steven J.; Saenger, K. L.; Chu, J. O.; Ouyang, Q.; Ott, J. A.; Rooks, M. J.; Canaperi, D.; Tornello, J. A.; Jahnes, C.; Steen, S.E.

doi:10.1049/el:20031082

Cited by 14 publications

(16 citation statements)

References 2 publications

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“…For the device shown in Fig. 3(a), was only 2 , while a previous device [9] with , also shown in Fig. 3(b), had of only 175 GHz at V. The RF measurement results for devices with nm are shown in Fig.…”

Section: Rf Characteristicsmentioning

confidence: 85%

“…The RF characteristics were measured using devices configured in a two-finger pi-geometry, with total gate width, , of either 20 or 40 m. An optimized gate pad geometry was used to eliminate resistance arising from the overlap of the pad metal with the T-gate metal [9]. S-parameter measurements were performed using an HP8510C network parameter analyzer, on both the active devices as well as open-circuit and short-circuit geometries.…”

Section: Rf Characteristicsmentioning

confidence: 99%

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Laterally scaled Si-Si/sub 0.7/Ge/sub 0.3/ n-MODFETs with f/sub max/>200 GHz and low operating bias

Koester

Saenger

Chu

et al. 2005

IEEE Electron Device Lett.

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Section: Rf Characteristicsmentioning

confidence: 85%

Section: Rf Characteristicsmentioning

confidence: 99%

Laterally scaled Si-Si/sub 0.7/Ge/sub 0.3/ n-MODFETs with f/sub max/>200 GHz and low operating bias

Koester

Saenger

Chu

et al. 2005

IEEE Electron Device Lett.

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“…1 Because the silicon quantum well containing the electrons is strained by up to 2%, the electron mobility of these structures is as much as a factor of five larger than that of unstrained silicon fieldeffect transistors ͑FET͒ at room temperature, offering the prospect of high speed operation. At low temperatures, electron mobilities as high as 5.2ϫ10…”

mentioning

confidence: 99%

Coulomb blockade in a silicon/silicon–germanium two-dimensional electron gas quantum dot

Klein

Slinker

Truitt

et al. 2004

Applied Physics Letters

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We report the fabrication and electrical characterization of a single electron transistor in a modulation doped silicon/silicon-germanium heterostructure. The quantum dot is fabricated by electron beam lithography and subsequent reactive ion etching. The dot potential and electron density are modified by laterally defined side gates in the plane of the dot. Low temperature measurements show Coulomb blockade with a single electron charging energy of 3. Silicon-germanium modulation doped field-effect transistors ͑MODFETs͒ are potentially attractive devices for high-speed, low noise communications applications, where low cost and compatibility with complementary metaloxide-semiconductor logic are desirable.1 Because the silicon quantum well containing the electrons is strained by up to 2%, the electron mobility of these structures is as much as a factor of five larger than that of unstrained silicon fieldeffect transistors ͑FET͒ at room temperature, offering the prospect of high speed operation. At low temperatures, electron mobilities as high as 5.2ϫ10 5 cm 2 /V s have been reported, 2,3 raising the possibility of lithographically patterned quantum devices.Development of quantum devices in silicon MODFETs is of particular interest, because silicon is unique among the elemental and binary semiconductors in that it has an abundant nuclear isotope of spin zero. Silicon also has very small spin orbit coupling. Together, these two features provide only weak channels for electron spin relaxation; the electron spin dephasing time T 2 for phosphorus-bound donors has been measured to be as long as 3 ms at 7 K. 4 Kane has pointed out the advantages of nuclear spins in silicon for quantum computation, 5 and his scheme has been extended to electrons in SiGe heterostructures.6 Following Loss and DiVincenzo, 7 specific schemes have been proposed for spin-based quantum computation in silicon-germanium electron quantum dots. 8,9Here we demonstrate a quantum dot fabricated in a layered silicon/silicon-germanium ͑Si/SiGe͒ heterostructure that includes a strained Si quantum well containing a twodimensional electron gas ͑2DEG͒. Even with recent advances in the growth of high mobility SiGe modulationdoped heterostructures, producing lithographically defined n-type quantum dots with periodic Coulomb blockade has been challenging. The fabrication of highly isolated Schottky top gates is particularly difficult. 10,11 Due to the lattice mismatch between layers of different Ge fraction, misfit dislocations must be present to relieve the strain in the SiGe buffer layer. Misfit dislocations terminate in threading arms running up to the heterostructure surface, and these threading arms may play a role in forming a conductive path between top Schottky contacts and the 2DEG later. We have avoided this problem by fabricating a dot with highly isolated side gates formed from the 2DEG itself.The Si/SiGe heterostructure used here was grown by ultrahigh vacuum chemical vapor deposition.2 The 2DEG sits near the top of 80 Å of strained Si grown on a s...

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“…The two devices show similar trend with maximum values of f T and f max obtained at V G = 0.1~0.2V for 2-finger device (solid lines) and at around 0 V for 10-finger device (dashed lines). Similar gate bias dependence is also reported in [1] and [10].…”

Section: Electrical Characterizationssupporting

confidence: 88%

Si-based multi-finger N-MODFET RF power devices

Yuan

Jiang

Croke³

et al.

Digest of Papers. 2005 Topical Meeting on Silicon Monolithic Integrated Circuits in RF Systems, 2005.

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We report, for the first time, on the fabrication and characterizations of multi-finger n-type Si/SiGe modulation doped FETs (MODFET) for RF power amplifications. Under bias of V DS =5V, V GS =0V and continuous wave operation, load-pull measurements at 2 GHz from a 10-finger n-MODFET with a gate width of 500 (750) µm show that a maximum output power of 12 (14) dBm, power gain at 1 dB compression of 15 (16) dB, and maximum power added efficiency of 12 (15) % of MODFET device have been achieved. Index Terms -Load-pull, MODFET, power device, RF, SiGe.

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80 nm gate-length Si/Si _0.7 Ge _0.3 n -MODFET with 194 GHz f _max

Cited by 14 publications

References 2 publications

Laterally scaled Si-Si/sub 0.7/Ge/sub 0.3/ n-MODFETs with f/sub max/>200 GHz and low operating bias

Laterally scaled Si-Si/sub 0.7/Ge/sub 0.3/ n-MODFETs with f/sub max/>200 GHz and low operating bias

Coulomb blockade in a silicon/silicon–germanium two-dimensional electron gas quantum dot

Si-based multi-finger N-MODFET RF power devices

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80 nm gate-length Si/Si 0.7 Ge 0.3 n -MODFET with 194 GHz f max

Cited by 14 publications

References 2 publications

Laterally scaled Si-Si/sub 0.7/Ge/sub 0.3/ n-MODFETs with f/sub max/>200 GHz and low operating bias

Laterally scaled Si-Si/sub 0.7/Ge/sub 0.3/ n-MODFETs with f/sub max/>200 GHz and low operating bias

Coulomb blockade in a silicon/silicon–germanium two-dimensional electron gas quantum dot

Si-based multi-finger N-MODFET RF power devices

Contact Info

Product

Resources

About

80 nm gate-length Si/Si _0.7 Ge _0.3 n -MODFET with 194 GHz f _max