SiGe quantum well infrared photodetectors on strained-silicon-on-insulator

Abstract

We demonstrate p-type SiGe quantum well infrared photodetectors (QWIPs) on a strained-silicon-on-insulator (sSOI) substrate. The sSOI system allows strain-balancing between the QWIP heterostructure with an average composition of Si 0.7 Ge 0.3 and the substrate, and therefore lifts restrictions to the active material thickness faced by SiGe growth on silicon or silicon-on-insulator substrates. The realized sSOI QWIPs feature a responsivity peak at detection wavelengths around 6 µm, based on a transition between heavy-hole states. The fabricated devices have been thoroughly characterized and compared to equivalent material simultaneously grown on virtual Si 0.7 Ge 0.3 substrates based on graded SiGe buffers. Responsivities of up to 3.6 mA/W are achieved by the sSOI QWIPs at 77 K, demonstrating the large potential of sSOI-based devices as components for a group-IV optoelectronic platform in the mid-infrared spectral region.

Mixed-Substituted Single-Source Precursors for Si1–xGex Thin Film Deposition

“…Yield: 6.802 g (13.72 mmol, 82%). 1 (60 mL) was prepared in a Schlenk tube. After addition of neat Si 2 Cl 6 (20.86 g, 77.60 mmol) at room temperature, the reaction solution was stirred for 1 h. All volatiles were removed under reduced pressure, and the highly viscous, colorless residue was extracted with n-hexane (40 mL).…”

Relaxation Delay of Ge‐Rich Epitaxial SiGe Films on Si(001)

“…[ 3,4 ] In photonics and optoelectronics, the realization of thick but pseudomorphic and Ge‐rich Si 1− x Ge x films could enable the implementation of double heterostructures [ 5 ] to advance the present, fully group‐IV‐based room temperature light‐emitting devices [ 6 ] or photodetectors. [ 7,8 ] For many of these applications, the Ge concentrations x for the thick but pseudomorphic Si 1‐x Ge x films (TPFs) should be ideally in the range between 50% and 100%, to ensure, e.g., large enough band offsets between the Si and SiGe layers. [ 5,9 ]…”

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advance the present, fully group-IV-based room temperature light-emitting devices [6] or photodetectors. [7,8] For many of these applications, the Ge concentrations x for the thick but pseudomorphic Si 1-x Ge x films (TPFs) should be ideally in the range between 50% and 100%, to ensure, e.g., large enough band offsets between the Si and SiGe layers. [5,9] However, the literature reports mainly focus on TPFs with low Ge contents, x < 0.5, [10][11][12][13][14][15][16][17][18] with only a few exceptions for which the critical thickness for pronounced relaxation was evaluated for single Ge concentrations of about 55%.

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Epitaxial Growth of Planar Hutwires on Silicon‐on‐Insulator Substrates

“…This assumption is understandable considering that the growth of 2D Ge/Si quantum wells or intermixed SiGe quantum dots on SOI has been demonstrated before. [6,25,26] However, the transfer of HWs to an SOI platform is not straightforward due to three reasons: 1) the typically increased surface roughness of SOI substrates as compared with Si bulk substrates with ultralow miscut of less than 0.05°used in the original work, [14] 2) dewetting of SOI substrates at the typical degassing temperatures, [27][28][29] and 3) the delicate window of growth parameters in which HWs form. The possibility of HW formation on SOI substrates was stated in the study by Zhang et al, [14] but details regarding related growth parameters and resulting wire lengths were not discussed there.…”