An organic semiconductor device for detecting ionizing radiation on a cellular level

摘要

Microdosimetry describes the energy deposition of ionizing radiation on a microscopic scale by quantifying how Linear Energy Transfer (LET) of any radiation type creates local biological or physical damage sites. It thus provides a model of damage on a molecular level (DNA). Microdosimetry characterizes cellular effects and is used for understanding radiation oncology and human exposure. Ideal detectors for these applications have the same physical size and radiation cross section as a (human) cell. That cross section is a strong function of its composition, density, and the incident radiation's quality. Consequently, an organic, nano/micro radiation sensor is highly desirable. Ideal materials for these devices have a high mobility, small carrier trapping times, high resistivity, and unit density. Devices produced from these materials would be "tissue equivalent." We present a solid state tissue equivalent detector using an organic semiconductor as the active region. Many of the difficulties associated with ultrahigh resistance devices are eased by our novel geometric approach. We present the design of a detector with an organic active region, effective solutions to the materials problems, and device responses to radiation.