Terahertz Si:B blocked-impurity-band detectors defined by nonepitaxial methods

Abstract

The molecular beam epitaxial (MBE) fabrication of blocked-impurity-band detectors (BIB) has been a technologically complex and delicate matter ever since its demonstration in silicon, and has not been adapted for other material systems offering detection onsets at lower terahertz frequencies. We report the fabrication and characterization of a vertical Si:B BIB, circumventing the intrinsically troublesome MBE growth of an ultrapure blocking layer by employing ion implantation. We present a thorough characterization of our device, which exhibits highly competitive figures of merits. Our results not only increase the accessibility of BIB fabrication tools for ultrasensitive terahertz detection but also open a road to other material systems.

Shallow Impurity States in Doped Silicon Substrates Enabling High Responsivity for Graphene Mid-Infrared Photodetectors

“…The photoconductive response of a highly doped Si:B sample (4.8 × 10 18 cm −3 ) was collected using the FTIR spectrometer from 4.5 to 26 μm (inset, Figure 1c). The photoconductivity response spectra have been observed in doped semiconductors, namely, Si:P, 36 Si:Sb, 37 Si:As, 38 and Si:B, 3 with the photoconductivity response range up to 40 μm and the photoresponse range for Ge:Sb, 39 Ge:B, 40 and GaAs:Te 5 up to 300 μm. When the concentration of impurity increases, the photoconductivity response extends to the longer wavelength because of the broadening of the impurity band.…”

“…The capabilities of mid-infrared photodetection are highly desirable for many applications such as spectroscopy, chemical and biomolecular sensing, infrared imaging, night vision, security, and industry. , Silicon (Si) photodetectors based on complementary metal-oxide-semiconductor (CMOS) technology are of low cost and have maturity, high performance, and high level of integration with electronics from the deep ultraviolet (UV) to near-infrared (IR) region. Photodetection beyond the near-IR region typically is based on either thermal photodetection (i.e., pyroelectric, bolometer, thermocouple, and thermopile detectors), narrow band gap semiconductors (i.e., InSb, InGaAs, and HgCdTe detectors), or photoionization of shallow impurities (i.e., block-impurity bands using Si:Ga, Si:B, and GaAs:Te detectors). − Thermal photodetectors have low sensitivity, have a long response time, and often require human intervention. The other photodetectors require cryogenic operation and complicated fabrication processes that are only accessible for small-volume and high-value markets and cannot compensate for the demands of markets such as Si detectors.…”

Blocked impurity band very long wavelength infrared detector

“…A c c e p t e d https://engine.scichina.com/doi/10.1360/SSPMA-2020-0309  厚的垂直结构 BIB 探测器 [40] 。 离子注入的优点在于能精确控制杂质的浓度、 均匀性和掺杂区域等。目前，应用较多的还是外延生长型 BIB 器件，离子注入的方法主要用于制备 Ge 基和 GaAs 基 BIB 探测器。 图 6 背照式(a) 和前照式(b)BIB 探测器结构图 [17] 。图片来自文献，并获得授权 Figure 6 Structure of back-(a) and front-illuminated (b) BIB detector [17] . Reprinted with permission.…”

The research progress of Si-based blocked-impurity-band infrared detecting materials and detectors

“…在5 K温度下, 偏压1.2 V, 背入射式器 件的黑体响应率为1.36 A/W, 暗电流为7.9×10 −9 A, 计 算得到此时的黑体探测率为1.6×10 11 Jones. 与同波段 BIB探测器相比, 我们的这一指标接近于Rauter等人 [48] 制备的Si:B型BIB探测器, 但低于由RVS生产的应用于…”