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PURPOSE A new type of electronic dosimeter is presented, capable of discerning between the doses of gamma photons and neutrons in a mixed beam as found in Boron Neutron Capture Therapy (BNCT). We introduce a real-time dosimeter based on a thick gate Field Oxide Field Effect Transistor (FOXFET) covered with a neutron converter layer containing gadolinium. METHODS To sensitize the FOXFET dosimeter to neutron fluxes, a converter layer containing gadolinium oxide particles embedded in photoresines was deposited over the sensor surface. Mixed neutron-gamma field configurations with different neutron energy spectra were used to assess the FOXFET response, considering different thicknesses of the neutron converter layer. RESULTS The total gamma sensitivity of the devices resulted to be 43 mV/Gy. The responses of sensors with different converter layer thicknesses irradiated with different neutron spectra are simulated using GEANT4 code. The response to photons is not significantly modified with thin conversion layers when used in water medium. CONCLUSIONS A real-time dosimeter comprising a pair of FOXFET sensors-only one of them with a gadolinium neutron converter layer -allows the simultaneous measurement of gamma dose and neutron flux during BNCT irradiations. This article is protected by copyright. All rights reserved.

This article presents the design, fabrication, and characterization of an integrated differential dosimeter based on the mismatch of two identical field oxide MOS transistors (FOXFETs). This dosimeter was fabricated in a high-voltage $0.35~\mu \mathrm {m}$ CMOS process, where the FOXFET and the biasing circuit were integrated in the same chip. The FOXFET as a single device and the whole circuit as an integrated differential sensor were characterized regarding its response to both radiation and temperature. The differential sensor showed low temperature sensitivity, 320 times lower than that of the single FOXFET, while it also showed a reduction in radiation sensitivity only in a factor of 1.6. These results drastically improved the temperature error factor (TEF), calculated to be 23 mrad/°C. Moreover, the bias-controlled cycled measurement technique was successfully implemented by improving the dose range up to 9.4 krad. Finally, the temperature rejection performance was assessed in real-time measurements during exposure to radiation, and the sensitivity of the dosimeter showed no change with temperature.

We present a differential interface circuit to bias and read chalcogenide-based resistive gas sensors. The topology of the circuit is discussed and simulated using a commercial CMOS technology of 180 nm. The main advantages of the proposed circuit are: low power consumption, wide range of input sensing resistors and its possibility to operate under non-controlled ambient temperature. Results show that the circuit is capable of reading sensing resistances within a range between 2.4 MΩ and 100 MΩ with a measurement uncertainty of 1%. The noise of the circuit was found to be the limiting factor of the measurement accuracy. In the case of a sensing resistance of 50 MΩ (close to the middle of the operating range) the measurement uncertainty is below 0.05 %.

This paper presents the characterization of a thick gate oxide MOSFET for radiotherapy in-vivo dosimetry. The device is an N-channel transistor fabricated in a standard CMOS process using the Field Oxide as gate insulator. Sensitivity, fading, gate bias voltage dependence, percentage depth dose and angular response were assessed using a 6 MV LINAC. Experimental results showed that it is possible to estimate dose with a 3% uncertainty in a range up to 85 Gy with an average sensitivity of 62 mV/Gy. The measurement system noise equivalent dose is 3 mGy. Fil: García Inza, Mariano Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Cassani, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Carbonetto, Sebastián Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Casal, M.. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; Argentina Fil: Redin, Eduardo Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Faigon, Adrián Néstor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina

In this paper, a Floating Gate transistor designed and fabricated to be used as a radiation sensor is presented, and the charge injection process through an injection electrode is studied. The device was successfully charged, and the injection process was simulated in a SPICE software, considering that the injection mechanism was Fowler-Nordheim tuneling. The parameters for the Fowler-Nordheim current were found and simulations successfully reproduced the measurements. These simulations will allow to improve the desing and the charge injection setup.

In this paper we present a new dosimeter based on a pair of thick gate oxide MOSFET sensors. A differential circuit topology with a feedback loop provides stabilized output with selectable sensitivity amplification for real time in vivo dosimetry. Radiation response shows a wide linear output range and an effective thermal rejection. These properties make this circuit suitable for dose control in radiotherapy applications. Fil: Garcia Inza, Mariano Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Carbonetto, Sebastián Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Lipovetzky, José. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Faigon, Adrian Nestor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina

In this paper a CMOS reading circuit for memristor-based RRAM (Resistive Random Access Memory) cell is described. Simulations for one cell, 4 by 4 nMOS-accessed-array and extension to N by N nMOS-accessed-array are presented. The proposed circuit is based on CMOS inverters, which result in a simple low area architecture and in a non-destructive operation. Resistive switching memristor is used as reading reference. Simulations were performed in $0.5\ \mu \text{m}$ and 180 nm CMOS technology and using memristor model available in bibliography.

Fil: Sambuco Salomone, Lucas Ignacio. Universidad de Buenos Aires. Facultad de Ingenieria. Departamento de Fisica. Laboratorio de Fisica de Dispositivos Microelectronica; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas; Argentina

The offset of a Miller amplifier is mainly due to an imperfect matching between its inputs. When the input transistors are MOSFETs, the exposure to ionizing radiation affect the threshold voltage of both transistors. With proper polarization, the shift in the threshold voltage impoverishes the matching in the input, increasing the offset. Hence, measuring the change in the offset during irradiation, one can estimate the absorbed radiation dose. In this work, a theoretical analysis is presented in order to establish the effect of ionizing radiation on the different blocks of the Miller amplifier. The design of a Miller amplifier and its fabrication on an integrated circuit for testing is described. The design and assembly of a dedicated hardware and software for data acquisition is also described. First results on the fabricated dosimeter in a 0.6μm commercial CMOS technology show a sensitivity of 60 mV/Gy and a resolution of 4 cGy.

This paper presents a new technique to build MOS dosimeters using unmodified standard CMOS processes. The devices are n-channel MOS transistors built with the regular Field Oxide as a thick radiation-sensitive gate. The devices were fabricated in two different commercial m CMOS processes, gate oxide thicknesses of nm and nm. Responsivities up to 4.4 mV/rad with positive bias, and 1.7 mV/rad with zero gate bias were obtained in the thicker oxides. The effect of charge trapped in the oxide and interface states on the shift in the threshold voltage are analyzed. Fil: Lipovetzky, José. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: García Inza, Mariano Andrés. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Carbonetto, Sebastián Horacio. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Carra, Martin Javier. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina Fil: Redin, Eduardo Gabriel. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina Fil: Sambuco Salomone, Lucas Ignacio. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina Fil: Faigon, Adrián Néstor. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

We present the design and fabrication in a standard CMOS process of a chip that gathers several structures and circuits for ionizing radiation dosimetry. It includes already tested performance thick gate oxide transistors of different areas and other experimental circuits such as a fully integrated differential dosimeter, floating gate structures, and various types of differential amplifiers. First experimental results are presented.

An Interoperable Process Design Kit (iPDK) was developed for the scalable CMOS process SCN3ME provided by ON Semiconductors, reachable across MOSIS. It includes DRC and LVS rules, SPICE models, technology files, verification and extraction files, execution scripts, symbol library and parametric cells (PCells). Then, using the iPDK, a set of standard digital cells were developed. A test chip was designed and fabricated. Measurements results are presented.

Four different N-well Hall Plate geometries were designed and fabricated in a 0.5μm CMOS process provided by MOSIS. Different shapes, sizes, contact distribution and dimensions were used in order to characterize Hall Plate sensitivity and resistance in a range of temperatures from −40°C up to 165°C. To remove the offset a four-phase current spinning method was used. The results show a better sensitivity performance in the cross-shaped whereas the small square shape has a slight improvement in the SNR behavior. The sensitivity of the different Hall Plate geometries was simulated using a model based on finite-element showing good agreement with the measurements.

Through the injection of a Fowler-Nordheim tunnel current or the inversion of oxide fields during irradiation (Radiation-Induced Charge Neutralization), the oxide charge trapped in thick-oxide (300 nm) commercial RADFETs, often called QOT could be erased. Novel trapped-hole and interface characteristics were observed after treatments of this type at high doses. With both erasure techniques, it was possible only to neutralize a fraction of the oxide trapped charge. A non negligible amount of charge and border traps is deemed here to be “intractable”. That adjective an a symbol, QIN, are introduced for the first time in this paper. Later sections discuss the possible impact of these results. The conclusion for dosimetry is that a “reusable RADFET” dosimeter, working up to an unprecedented dose before wearing out, may be a practical possibility.

A new design for an on-chip ionizing radiation sensor is presented. The circuit consists of two source-coupled Field Oxide Transistors biased with the same drain current through a feedback loop, whose offset in the gate voltage is amplified. This paper explains the design criteria for integration of the sensor in a 0.5 μm CMOS process. The design was validated with simulations and showed the expected behavior.

Pulsed capacitance-voltage (C-V) technique was applied to the study of electron trapping in MOS capacitors with amorphous Al 2 O 3 as insulating layer. This technique allows to observe fast trapping/detrapping processes as it measures a C-V curve in a few hundred of microseconds. The dependences of the C-V curve with the applied bias and the charging time was investigated. A positive displacement of the voltage value corresponding to a constant capacitance (V C ) was observed as the top level of the pulsed signal is increased and a linear dependence was obtained. Regarding the charging time, the positive V C -shift showed a logarithmic dependence, evidencing the presence of a tunneling front advancing into the dielectric. Moreover, a fixed V C -shift was observed after charging with long times (~500 ms), related to traps that can not be discharged between measurements.

This paper presents a differential MOSFET sensor reading technique based on the bias controlled cycled measurement. The circuit was implemented, and tested with gamma radiation from a 60-cobalt source. Temperature rejection performance was assessed during the exposure in real-time measurements. The results show that in comparison with a single MOSFET dosimeter the thermal drift is 20 times smaller and the radiation sensitivity is approximately 10% higher. The switched biasing allows to extend the measurement range beyond MOSFET's threshold voltage saturation. Fil: García Inza, Mariano Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería ; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina Fil: Carbonetto, Sebastián Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería ; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina Fil: Lipovetzky, José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería ; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina Fil: Carra, Martin Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería ; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina Fil: Sambuco Salomone, Lucas Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería ; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina Fil: Redin, Eduardo Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería ; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina Fil: Faigon, Adrián Néstor. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería ; Argentina

The evolution of the threshold voltage of MOS dosimeters during irradiation under switched bias is investigated with the aim of using the sensors with a new biasing technique. The devices response to a bias change does not only depend on the instant threshold voltage and bias, and may lead to non-monotonical behavior under fixed bias following the switch. This work shows experimental evidence for this effect and presents a simple model based on oxide charge buildup and neutralization. The proposed model reproduces the experimental data assuming the existence of two types of hole traps in the oxide. Physical interpretations of the results are discussed. Fil: Faigon, Adrián Néstor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Física de Dispositivos Microelectrónica; Argentina Fil: García Inza, Mariano Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Física de Dispositivos Microelectrónica; Argentina Fil: Lipovetzky, José. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Física de Dispositivos Microelectrónica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Redin, Eduardo Gabriel. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Física de Dispositivos Microelectrónica; Argentina Fil: Carbonetto, Sebastián Horacio. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Física de Dispositivos Microelectrónica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Sambuco Salomone, Lucas Ignacio. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Física de Dispositivos Microelectrónica; Argentina Fil: Berbeglia, F.. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Física de Dispositivos Microelectrónica; Argentina

This work proposes a new biasing technique to extend the dose measurement range of MOS dosimeters. The technique consists on alternating stages of positive oxide charge buildup with stages of radiation induced charge neutralization, maintaining an uniform sensitivity along the whole measurement. The technique was applied with 70 nm MOS dosimeters, extending the dose measurement range from less than a kilogray to more than 675 kGy without showing wear effects. An initial saturation of interface traps creation ensures repeatability in the responses.

Charge trapping dynamics induced by exposition to γ-ray (60Co) radiation and bias switching in MOS capacitors with atomic layer deposited Al2O3 as insulating layer was studied. Electrical characterization prior to irradiation showed voltage instabilities due to electron tunneling between the substrate and preexisting defects inside the dielectric layer. Real-time capacitance-voltage (C-V) measurements during irradiation showed two distinct regimes: For short times, the response is strongly bias dependent and linear with log(t), consistent with electron trapping/detrapping; for long times, the voltage shift is dominated by the radiation-induced hole capture being always negative and linear with dose. A simple model that takes into account these two phenomena can successfully reproduce the observed results. Fil: Sambuco Salomone, Lucas Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Kasulin, A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Lipovetzky, José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Carbonetto, Sebastián Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: García Inza, Mariano Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Redin, Eduardo Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Berbeglia, F.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina Fil: Campabadal, F.. Consejo Superior de Investigaciones Científicas; España Fil: Faigon, Adrián Néstor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina

Al2O3-based dielectrics are currently considered as promising materials to use in nonvolatile memories. The electron trap density in this material is much higher than in conventional SiO2, being their characteristics critical for the application. Conventional capacitance-voltage (C-V) techniques were used to study the main effects of the electron traps on the electrical characteristics of MOS capacitors with atomic layer deposited Al2O3 as insulating layer. More detailed information about the trapping kinetics was obtained through the study of the constant capacitance voltage transient. Two different types of traps were found. One is responsible for the instabilities observed in C-V measurements, the other has characteristic trapping times three orders longer. A physical model is presented to explain the observed trapping kinetics exhibiting good agreement between experiments and simulations. The energy levels of the studied traps were determined at 2.2 and 2.6 eV below the Al2O3 conduction band, with den...