No abstract

Four groups of grain sizes of LiF:Mg,Cu,P material were chosen for the experiment. The influences of the grain size on the photon energy response and dose response have been examined in the intewal of 28-1250 keV and the dose range 0.190 Gy of ' %o y-rays. The experimental results show that both the energy response and the dose response are grain size dependent. A possible correlation seems to exist between the energy response v(E) and the dose response f ( D ) . A brief discussion is provided.

Random telegraph signal (RTS) noise shows discrete and stochastic switching in two or more states at a drain current or threshold voltage. The capture and emission of carriers in individual traps near a silicon–gate insulator film interface induce RTS noise phenomena. RTS noise has become a crucial problem in analog devices and other devices. To suppress RTS noise, it is necessary to determine the energy level of traps. Time constant ratio has a strong relationship with the energy level of traps in gate insulator films. In this paper, we extract a large number of RTS data sets with large-scale array test patterns and evaluate the gate-bias voltage dependences of time constant ratio and amplitude. We demonstrate that the energy level of traps distributes uniformly at a drain current of at least 0.1–1.0 µA.

Random telegraph signal (RTS) noise in small gate area metal oxide semiconductor (MOS) transistors occurs frequently and causes serious problems in the field of flash memories and complementary MOS (CMOS) image sensors. The trap in the gate insulator, which is considered the origin of RTS, varies widely in terms of spatial location and energy level, so that RTS characteristics including the amplitude and time constants have large variability by nature and statistical analysis of RTS should become indispensable. In this paper, we propose a high-speed RTS measurement system with a newly developed test circuit and discuss the drain current and temperature dependences of RTS amplitude distributions. Moreover, we expand the sampling frequency between 0.47 Hz -3.0 MHz and the observation length up to about 4 h and can thereby observe some anomalous RTSs such as ones with long time constants, ones generated abruptly, and ones disappearing.

No abstract