High mobility holes in a strained Ge quantum well grown on a thin and relaxed Si0.4Ge0.6/LT-Si0.4Ge0.6/Si(001) virtual substrate

Myronov, Maksym; Leadley, D. R.; Shiraki, Y.

doi:10.1063/1.3090034

Cited by 18 publications

(6 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, relaxed Ge does not out-perform the current stateof-the-art uni-axially strained Si. Considerably higher hole velocities are reported for uni-axially and bi-axially compressively strained Ge [3][4][5][6][7][8][9]. The fabrication of uni-axially compressively strained Ge requires the implementation of embedded GeSn with a substitutional Sn content far above the solubility limit of 0.5-1% [10].…”

Section: Introductionmentioning

confidence: 99%

“…The fabrication of uni-axially compressively strained Ge requires the implementation of embedded GeSn with a substitutional Sn content far above the solubility limit of 0.5-1% [10]. This complication explains the high research interest in bi-axially strained Ge, grown on top of SiGe strain relaxed buffers (SRBs) [5][6][7][8][9]11,12]. Important parameters from device integration point of view are, amongst others, the surface smoothness, the material quality (crystallinity), and the threading dislocation density (TDD).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Smooth and high quality epitaxial strained Ge grown on SiGe strain relaxed buffers with 70–85% Ge

Loo

Souriau

Ong

et al. 2011

Journal of Crystal Growth

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Smooth and high quality epitaxial strained Ge grown on SiGe strain relaxed buffers with 70–85% Ge

Loo

Souriau

Ong

et al. 2011

Journal of Crystal Growth

View full text Add to dashboard Cite

“…Even though high mobility 2DHGs have been achieved [18][19][20][21][22], Ge 2DHG based MODFETs with high mobility operating at cryogenic temperatures have, to the best of our knowledge, not been investigated up to now. Operation of a ptype Ge channel MODFET has been reported at an operating temperature of T = 77 K [23] and 2DHG MOSFETs with Ge channels have also been investigated [24].…”

Section: Introductionmentioning

confidence: 99%

High mobility Ge 2DHG based MODFETs for low-temperature applications

Weißhaupt

Funk

Oehme

et al. 2023

Semicond. Sci. Technol.

View full text Add to dashboard Cite

- Modulation-doped field-effect transistors (MODFET) that are typically based on either a two-dimensional electron gas (2DEG) or a two-dimensional hole gas (2DHG) are highly suitable for low-temperature applications due to the high mobilities attained by the charge carriers in the device channel. The Ge 2DHG is particularly interesting, since Ge exhibits the highest hole mobility among all semiconductors. In this paper, we report on the temperature-dependent direct current (DC)-characteristics of normally-on MODFETs based on a high mobility Ge 2DHG. Here, we specifically investigate device characteristics down to cryogenic temperatures and analyse the impact of different MOD-doping on device performance. We find that the largest On-Off ratio of I On/I Off = 3.2⋅106 and lowest Sub-Threshold Swing (SS) of (SS) of SS = 64 mV/dec at a temperature of T = 7.5 K are attained for a MOD-doping of N A = 5⋅1017 cm-3, while the highest effective mobility µ eff = 864 cm2/Vs is obtained from a device with a MOD-doping of N A = 1.1⋅1018 cm-3. Furthermore, while effective mobilities in the devices are strongly reduced compared to Hall mobilities measured in the unstructured Ge 2DHGs, both quantities can be seen to follow a similar trend. Our results motivate further investigations of Ge 2DHG MODFETs for applications in cryogenic low-noise amplifiers, besides their well-established potential for spintronic applications.

show abstract

“…However, relaxed Ge does not outperform the current state of the art uni-axially strained Si. Considerably higher hole velocities are reported for uni-axially and bi-axially compressively strained Ge [2][3][4][5][6][7]. The fabrication of uni-axially strained Ge requires the implementation of embedded GeSn with a substitutional Sn content far above the solubility limit of 0.5 -1%.…”

Section: Introductionmentioning

confidence: 99%

Optimized Post-CMP and Pre-Epi Cleans to Enable Smooth and High Quality Epitaxial Strained Ge Growth on SiGe Strain Relaxed Buffers

Loo

Souriau²,

Ong

et al. 2012

SSP

View full text Add to dashboard Cite

Further improving complementary metal oxide semiconductor (CMOS) performance beyond the 15 nm generation likely requires the use of high mobility materials like Ge for pMOS devices. However, Ge pMOS devices made in relaxed Ge do not outperform current state of the art uni-axially strained Si pMOS devices. This explains the current interest in compressively strained Ge like bi-axially strained Ge grown on top of SiGe Strain Relaxed Buffers. From a device integration point of view, the surface smoothness of the strained Ge layer is an important parameter which has so far not widely been reported in literature, in contrast to other parameters like the material quality (crystallinity) and the threading dislocation density. In this paper we report the post-CMP and pre-epi cleans which are required to obtain contamination free SiGe surfaces to enable defect free strained Ge growth without reoccurrence of the surface roughening. We will demonstrate the epitaxial growth of fully strained 20 nm thick Ge epitaxially grown on top of SiGe Strain Relaxed Buffers with 85% Ge with a surface roughness as low as 1.6 Å (as measured on areas of 10×10 µm2).

show abstract

High mobility holes in a strained Ge quantum well grown on a thin and relaxed Si0.4Ge0.6/LT-Si0.4Ge0.6/Si(001) virtual substrate

Cited by 18 publications

References 13 publications

Smooth and high quality epitaxial strained Ge grown on SiGe strain relaxed buffers with 70–85% Ge

Smooth and high quality epitaxial strained Ge grown on SiGe strain relaxed buffers with 70–85% Ge

High mobility Ge 2DHG based MODFETs for low-temperature applications

Optimized Post-CMP and Pre-Epi Cleans to Enable Smooth and High Quality Epitaxial Strained Ge Growth on SiGe Strain Relaxed Buffers

Contact Info

Product

Resources

About