scholarly journals Structure and Optical Properties of Co-Sputtered Amorphous Silicon Tin Alloy Films for NIR-II Region Sensor

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4076
Author(s):  
Xiang-Dong Jiang ◽  
Ming-Cheng Li ◽  
Rui-Kang Guo ◽  
Ji-Min Wang
Keyword(s):  
Amorphous Silicon ◽  
Deposition Temperature ◽  
Near Infrared ◽  
Dark Conductivity ◽  
Linear Variation ◽  
Sensitive Layer ◽  
Tem Analysis ◽  
Alloy Films ◽  
Non Invasive ◽  
Xrd And Tem

Near-infrared brain imaging technology has great potential as a non-invasive, real-time inspection technique. Silicon-tin (SiSn) alloy films could be a promising material for near-infrared brain detectors. This study mainly reports on the structure of amorphous silicon tin alloy thin films by Raman spectroscopy to investigate the influence of doped-Sn on an a-Si network. The variations in TO peak caused by the increase in Sn concentration indicate a decrease in the short-range order of the a-Si network. A model has been proposed to successfully explain the non-linear variation in Raman parameters of ITA/ITO and ILA+LO/ITO. The variations of Raman parameters of the films with a higher deposition temperature indicate the presence of SiSn nanocrystals, though the SiSn nanocrystals present no Raman peaks in Raman spectra. XRD and TEM analysis further illustrate the existence of nanocrystals. The ratio of photo/dark conductivity and optical bandgap results demonstrate that the films can be selected as a sensitive layer material for NIR-II region sensors.

Amorphous Silicon Selenium Alloy Film Deposited Under Hydrogen Dilution

1991 ◽  
Vol 219 ◽  
Author(s):  
Muzhi He ◽  
Guang H. Lin ◽  
J. O'M. Bockris
Keyword(s):  
Amorphous Silicon ◽  
Chemical Vapor ◽  
Selenium Concentration ◽  
Alloy Film ◽  
Dark Conductivity ◽  
Flow Rate Ratio ◽  
Selenium Atom ◽  
Alloy Films ◽  
Hydrogen Dilution ◽  
Photo Response

ABSTRACTAmorphous silicon selenium alloy films were prepared by plasma enhanced chemical vapor deposition with hydrogen dilution. The flow rate ratio of hydrogen to silane was about 8:1. Amorphous silicon selenium alloy was found to have an optical bandgap ranging from 1.7 eV to 2.0 eV depending on the selenium concentration in the films. The light to dark conductivity ratios of the alloy films are ∼ 104. The optical and electrical properties, Urbach tail energy and sub-bandgap photo response spectroscopy of the alloy film were investigated. The film quality of the alloy deposited with hydrogen dilution is greatly improved comparing to that of the alloy film deposited without hydrogen dilution. The electron spin resonance experiment shows that selenium atom is a good dangling bond terminator.

Effect of Deposition Temperature on the Photoresponse of Crystallized Hydrogenated Amorphous Silicon Films

1994 ◽  
Vol 358 ◽  
Author(s):  
Nagarajan Sridhar ◽  
D. D. L. Chung ◽  
W. A. Anderson ◽  
J. Coleman
Keyword(s):  
Amorphous Silicon ◽  
Deposition Temperature ◽  
Laser Annealing ◽  
Hydrogenated Amorphous Silicon ◽  
Dark Conductivity ◽  
Silicon Films ◽  
Laser Crystallization ◽  
Furnace Annealing ◽  
C 50 ◽  
Hydrogenated Amorphous

ABSTRACTThe deposition temperature of hydrogenated amorphous silicon films deposited by dc glow discharge was found to affect the photoresponse (ratio of the photo to dark conductivity) after crystallization of the film. This effect depended on the crystallization technique. For crystallization by laser annealing, the photoresponse (0.15 - 1.5) increased with increasing deposition temperature (150 - 300 °C) due to the increase in SiH and SiH2 bonding, as shown by infrared spectroscopy. For crystallization by furnace annealing (e.g. 650 °C, 50 h), the photoresponse (0.08 - 0) decreased with increasing deposition temperature (150 - 300 °C) due to the decrease in grain size and crystallinity as shown by x-ray diffraction; the complete loss in hydrogen during furnace annealing made the photoresponse low and the silicon-hydrogen bonding effect immaterial. Thus, laser crystallization at the highest deposition temperature gave the highest photoresponse.

Formation of Large, Orientation-Controlled, Nearly Single Crystalline Si Thin Films on SiO2 Using Contact Printing of Rolled and Annealed Nickel Tapes

2003 ◽  
Vol 762 ◽  
Author(s):  
Hwang Huh ◽  
Jung H. Shin
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
High Resolution ◽  
Amorphous Silicon ◽  
Tem Analysis ◽  
Contact Printing ◽  
Single Crystalline ◽  
High Resolution Tem ◽  
Lateral Crystallization ◽  
Si Films

AbstractAmorphous silicon (a-Si) films prepared on oxidized silicon wafer were crystallized to a highly textured form using contact printing of rolled and annealed nickel tapes. Crystallization was achieved by first annealing the a-Si film in contact with patterned Ni tape at 600°C for 20 min in a flowing forming gas (90 % N2, 10 % H2) environment, then removing the Ni tape and further annealing the a-Si film in vacuum for2hrsat600°C. An array of crystalline regions with diameters of up to 20 μm could be formed. Electron microscopy indicates that the regions are essentially single-crystalline except for the presence of twins and/or type A-B formations, and that all regions have the same orientation in all 3 directions even when separated by more than hundreds of microns. High resolution TEM analysis shows that formation of such orientation-controlled, nearly single crystalline regions is due to formation of nearly single crystalline NiSi2 under the point of contact, which then acts as the template for silicide-induced lateral crystallization. Furthermore, the orientation relationship between Si grains and Ni tape is observed to be Si (110) || Ni (001)

Near-infrared Inorganic Nanomaterials-based Nanosystem for Photothermal Therapy

Nanoscale ◽  
2021 ◽  
Author(s):  
Yufei Wang ◽  
Hongmin Meng ◽  
Zhaohui Li
Keyword(s):  
Photothermal Therapy ◽  
Near Infrared ◽  
Strong Absorption ◽  
Non Invasive ◽  
Inorganic Nanomaterials

The development of robust materials for treating diseases through non-invasive photothermal therapy (PTT) has attracted increasing attention in recent years. Among many types of nanomaterials, inorganic nanomaterials with strong absorption...

scholarly journals Exploring personalized postoperative non-invasive tissue oximetry in DIEP flap breast reconstruction

2021 ◽  
Author(s):  
Anouk A. M. A. Lindelauf ◽  
Nousjka P. A. Vranken ◽  
Rutger M. Schols ◽  
Esther A. C. Bouman ◽  
Patrick W. Weerwind ◽  
...  
Keyword(s):  
Early Detection ◽  
Breast Reconstruction ◽  
Near Infrared ◽  
Diep Flap ◽  
Baseline Measurement ◽  
Flap Surgery ◽  
Level Of Evidence ◽  
Non Invasive ◽  
Vascular Compromise ◽  
Tissue Oximetry

Abstract Early detection of vascular compromise after autologous breast reconstruction is crucial to enable timely re-exploration for flap salvage. Several studies proposed non-invasive tissue oximetry for early identification of ischemia of deep inferior epigastric perforator (DIEP) flaps. The present study aimed to explore the utility of non-invasive tissue oximetry following DIEP flap surgery using a personalized oxygenation threshold. Methods Patients undergoing immediate/delayed DIEP flap surgery were included in this prospective observational study. DIEP flap tissue oxygenation (StO2) was monitored continuously using near-infrared spectroscopy. A baseline measurement was performed by positioning one sensor at the marked position of the major inferior epigastric perforator on the abdomen. A new sensor was positioned postoperatively on the transplanted tissue. In unilateral procedures, postoperative StO2 values of the native breast were also obtained. Measurements were continued for 24 h. Results Thirty patients (42 flaps) were included. Fourteen patients (46.7%) had an uncomplicated postoperative course. A minor complication was observed in thirteen patients; in five patients, at least one major complication occurred, requiring re-exploration. Median StO2 readings were significantly lower in patients with major complications compared to uncomplicated cases. In fourteen unilateral DIEP flap procedures, StO2 values of the native breast were similar to the preoperative baseline measurement (92%; p = 0.452). Conclusions Non-invasive tissue oximetry following DIEP flap surgery could aid in early detection of vascular compromise. StO2 values of the native breast and abdominal wall preoperatively can be used interchangeably and can serve as personalized reference value. Level of evidence: Level IV, diagnostic / prognostic study.

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