Radiation Sensors Based on the Generation of Mobile Protons in Organic Dielectrics

Abstract

A sensing scheme based on mobile protons generated by radiation, including ionizing radiation (IonR), in organic gate dielectrics is investigated for the development of metal-insulator-semiconductor (MIS)-type dosimeters. Application of an electric field to the gate dielectric moves the protons and thereby alters the flat band voltage (VFB) of the MIS device. The shift in the VFB is proportional to the IonR-generated protons and, therefore, to the IonR total dose. Triphenylsulfonium nonaflate (TPSNF) photoacid generator (PAG)-containing poly(methyl methacrylate) (PMMA) polymeric films was selected as radiation-sensitive gate dielectrics. The effects of UV (249 nm) and gamma (Co-60) irradiations on the high-frequency capacitance versus the gate voltage (C-VG) curves of the MIS devices were investigated for different total dose values. Systematic improvements in sensitivity can be accomplished by increasing the concentration of the TPSNF molecules embedded in the polymeric matrix.

Reveal the Humidity Effect on the Phase Pure CsPbBr3 Single Crystals Formation at Room Temperature and Its Application for Ultrahigh Sensitive X‐Ray Detector

“…[8] Moreover, single crystals of perovskites have better air stability than the thin films prepared by the spin-coating method, which is more suitable for the long-term application of devices. [9][10][11] As a conversion device to convert an X-ray photon signal into an electrical signal, the X-ray detector is a key part of the X-ray application system and widely used in medical diagnostic radiotherapy, industrial flaw detection, safety detection, aerospace navigation and material analysis of scientific research, et al [12,13] The direct-detection semiconductor X-ray detector has a better sensitivity and energy resolution than the one using a scintillator. [14] Generally, high-performance direct-detection semiconductor X-ray detectors need to have high carrier mobility and charge carrier lifetime product for ensuring the holes and electrons have sufficient drift length, and high resistivity at room temperature.…”

Tunable Radiation Response in Hybrid Organic–Inorganic Gate Dielectrics for Low-Voltage Graphene Electronics

“…32 Mobile ion diffusion, where ions are drawn to the gate or semiconductor/dielectric interface in an electric field, has been observed in organic thin-film dielectrics. 9 However, the lack of correlation between gate bias polarity and shifting direction of the transfer curves (Figure 2a−c) suggests that the alternating organic−inorganic structure of Zr-SAND inhibits facile ion transport. In particular, diffusion is likely impeded by the physical presence of the inorganic oxide as well as its trap sites, which could potentially form dipoles with the Br − ions.…”

“…For this exposure condition, holes generated (or liberated mobile positive charges) in the gate dielectric are drawn toward the Si/SiO 2 interface while electrons (or liberated mobile negative charges) are repelled and move toward the graphene/Zr-SAND interface. 22 Although the resulting trap and/or mobile charge distribution is unknown, the rightward shift of V Dirac suggests an increase in net negative charge density in Zr-SAND near the graphene interface, 9,22,23 which is contrary to SiO 2 and high-κ gate dielectrics that exhibit predominately hole trapping. 7,24,25 Similarly, when the gate field polarity is reversed, as in the +V bias G-FETs, V Dirac shifts toward positive V g with increasing RE, although the magnitude of ΔV Dirac (0.07 V) at 23.1 μJ/cm 2 is 5-fold less than the −V bias devices.…”

“…In one example, an organic dielectric showed increased radiation-sensitivity due to mobile proton generation following photon irradiation. 9 On the other hand, proton irradiation had minimal effect on charge transport in devices incorporating silane-based SANDs, suggesting increased radiation tolerance. 10 More recent SAND chemistries have incorporated high-κ inorganic oxide layers in an effort to enhance the dielectric response, although the radiation response has not yet been characterized.…”

“…However, the radiation response of organic dielectrics is not well understood. In one example, an organic dielectric showed increased radiation-sensitivity due to mobile proton generation following photon irradiation . On the other hand, proton irradiation had minimal effect on charge transport in devices incorporating silane-based SANDs, suggesting increased radiation tolerance .…”