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Title: Charge multiplication effect in thin diamond films

Abstract

Herein, we report on the enhanced sensitivity for the detection of charged particles in single crystal chemical vapour deposition (scCVD) diamond radiation detectors. The experimental results demonstrate charge multiplication in thin planar diamond membrane detectors, upon impact of 18 MeV O ions, under high electric field conditions. Avalanche multiplication is widely exploited in devices such as avalanche photo diodes, but has never before been reproducibly observed in intrinsic CVD diamond. Because enhanced sensitivity for charged particle detection is obtained for short charge drift lengths without dark counts, this effect could be further exploited in the development of sensors based on avalanche multiplication and radiation detectors with extreme radiation hardness.

Authors:
; ; ;  [1];  [2]; ; ;  [3]; ; ; ; ;  [4]
  1. Division of Experimental Physics, Ruđer Bošković Institute, 10000 Zagreb (Croatia)
  2. CEA-LIST, Diamond Sensors Laboratory, Gif-sur-Yvette F-91191 (France)
  3. Division of Electronics and Informatics, Faculty of Science and Technology, Gunma University, Kiryu, Gunma 376-8515 (Japan)
  4. National Institutes for Quantum and Radiological Science and Technology, Takasaki, Gunma 370-1292 (Japan)
Publication Date:
OSTI Identifier:
22594450
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 4; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CHARGED PARTICLE DETECTION; CHEMICAL VAPOR DEPOSITION; DIAMONDS; ELECTRIC FIELDS; FILMS; LENGTH; MEMBRANES; MONOCRYSTALS; OXYGEN IONS; PHOTODIODES; RADIATION DETECTORS; RADIATION HARDNESS; SENSITIVITY; SENSORS; TOWNSEND DISCHARGE

Citation Formats

Skukan, N., E-mail: nskukan@irb.hr, Grilj, V., Sudić, I., Jakšić, M., Pomorski, M., Kada, W., Kambayashi, Y., Andoh, Y., Makino, T., Onoda, S., Sato, S., Ohshima, T., and Kamiya, T.. Charge multiplication effect in thin diamond films. United States: N. p., 2016. Web. doi:10.1063/1.4959863.
Skukan, N., E-mail: nskukan@irb.hr, Grilj, V., Sudić, I., Jakšić, M., Pomorski, M., Kada, W., Kambayashi, Y., Andoh, Y., Makino, T., Onoda, S., Sato, S., Ohshima, T., & Kamiya, T.. Charge multiplication effect in thin diamond films. United States. doi:10.1063/1.4959863.
Skukan, N., E-mail: nskukan@irb.hr, Grilj, V., Sudić, I., Jakšić, M., Pomorski, M., Kada, W., Kambayashi, Y., Andoh, Y., Makino, T., Onoda, S., Sato, S., Ohshima, T., and Kamiya, T.. 2016. "Charge multiplication effect in thin diamond films". United States. doi:10.1063/1.4959863.
@article{osti_22594450,
title = {Charge multiplication effect in thin diamond films},
author = {Skukan, N., E-mail: nskukan@irb.hr and Grilj, V. and Sudić, I. and Jakšić, M. and Pomorski, M. and Kada, W. and Kambayashi, Y. and Andoh, Y. and Makino, T. and Onoda, S. and Sato, S. and Ohshima, T. and Kamiya, T.},
abstractNote = {Herein, we report on the enhanced sensitivity for the detection of charged particles in single crystal chemical vapour deposition (scCVD) diamond radiation detectors. The experimental results demonstrate charge multiplication in thin planar diamond membrane detectors, upon impact of 18 MeV O ions, under high electric field conditions. Avalanche multiplication is widely exploited in devices such as avalanche photo diodes, but has never before been reproducibly observed in intrinsic CVD diamond. Because enhanced sensitivity for charged particle detection is obtained for short charge drift lengths without dark counts, this effect could be further exploited in the development of sensors based on avalanche multiplication and radiation detectors with extreme radiation hardness.},
doi = {10.1063/1.4959863},
journal = {Applied Physics Letters},
number = 4,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
  • In this paper, the effect of thin interfacial films of SiO[sub 2] ([approximately] 20 [Angstrom]) on the electrical characteristics of metal contacts fabricated on polycrystalline and homepitaxial diamond films is studied. The diamond films were grown using plasma-=enhanced chemical vapor deposition techniques. In order to minimize the effect of defects and/or hydrogen on the metal contact characteristics, these films were annealed at 950[degrees]C for 30 min. Metal-semiconductor contacts were formed by electron-beam evaporation of Al on both as-received and annealed polycrystalline films, whereas, Au metallization was used for the homoepitaxial film. Active diode areas were defined by a standard photolithographicmore » process. It has been demonstrated in this investigation that, in certain cases, the introduction of a thin SiO[sub 2] film at the interface between the metal and the diamond semiconductor film allows the fabrication of a rectifying contact that is not obtainable without the interfacial film.« less
  • Auger and electron energy loss spectroscopies were used to study chemical and structural properties of as-grown surfaces of boron-doped diamond thin films prepared by microwave plasma-assisted chemical vapor deposition. Results are compared to surface properties of as-deposited undoped diamond thin films. As the boron level in the film increased energy losses associated with [pi] electron bonds ([ital sp][sup 2] sites) were enhanced at the surface. Similarly, the surface oxygen level of the films increased with increasing boron content. On the other hand the characteristic diamond Raman peak at 1332 cm[sup [minus]1] was narrower than in the undoped films and themore » broad band at about 1500 cm[sup [minus]1] associated with nondiamond carbon decreased. Surface morphology micrographs obtained from scanning electron microscopy (SEM) measurements indicated that the introduction of boron enhances the appearance of the (111) planes. Surface characterization together with the Raman and SEM results suggest that boron doping enhances surface reactivity resulting in increased adsorption of oxygen and carbonaceous species following the growth process. This behavior has implications on surface treatments necessary for device applications.« less
  • Poly[5,5{prime}-bis(3-dodecyl-2-thienyl)-2,2{prime}-bithiophene] (PQT-12) is a conjugated polymer that shows promising performance ({micro} > 0.1 cm{sup 2}/V s) as a semiconductor for thin-film electronics. The electrical properties of PQT-12 thin films can vary by over 3 orders of magnitude depending on the chemistry of the substrate onto which they are deposited and on annealing conditions. The highest mobility is obtained in films annealed on a dielectric treated with a self-assembled monolayer of octadecyltrichlorosilane (OTS). Polymeric thin films were processed from either a solution of dissolved PQT-12 molecules in 1,2-dichlorobenzene or from a nanoparticle dispersion of the polymer in the same solvent (nPQT-12).more » In addition, the substrate surface chemistry was altered by spin coating on a bare SiO{sub 2} dielectric or on SiO{sub 2} treated with OTS. The microstructure of the two forms of polymer, as characterized using specular and grazing x-ray diffraction in addition to rocking curves, was compared and correlated with the electrical performance of the films as active layers in thin-film transistors. As-spun films of nPQT-12 are always more crystalline than those of PQT-12, independent of substrate chemistry. Consequently, carrier mobility in as-spun films is higher in nPQT-12 than in PQT-12. The presence of the OTS monolayer at the polymer/dielectric interface increases crystallinity of both PQT-12 and nPQT-12, without significantly affecting their texture. After annealing, the mobility in PQT-12 films and nPQT-12 films is comparable. Annealing causes the polymer films on OTS to undergo crystallite growth in the direction normal to the substrate. In nPQT-12, growth of the crystalline coherence length in the {pi}-{pi} stacking direction (i.e., parallel to the substrate and in the direction of charge transport) occurs as well. The mobility increase in nPQT-12 on OTS upon annealing is thus attributed to the higher crystallinity of the film. In PQT-12 films deposited on OTS on the other hand, annealing causes a decrease in the out-of-plane misorientation of neighboring crystallites without any significant grain growth in the plane of the film. The mobility increase in PQT-12 on OTS upon annealing is attributed to a better intergrain connectivity, in agreement with electrical modeling of the transistor characteristics using a mobility edge model.« less
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