Al-Ta'ii Hassan Maktuff Jaber, Mohd Amin Yusoff, Periasamy Vengadesh
Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
Department of Physics, Faculty of Science, University of Al-Muthanna, Samawah 66001, Iraq.
Sensors (Basel). 2015 Feb 26;15(3):4810-22. doi: 10.3390/s150304810.
Many types of materials such as inorganic semiconductors have been employed as detectors for nuclear radiation, the importance of which has increased significantly due to recent nuclear catastrophes. Despite the many advantages of this type of materials, the ability to measure direct cellular or biological responses to radiation might improve detector sensitivity. In this context, semiconducting organic materials such as deoxyribonucleic acid or DNA have been studied in recent years. This was established by studying the varying electronic properties of DNA-metal or semiconductor junctions when exposed to radiation. In this work, we investigated the electronics of aluminium (Al)/DNA/silicon (Si) rectifying junctions using their current-voltage (I-V) characteristics when exposed to alpha radiation. Diode parameters such as ideality factor, barrier height and series resistance were determined for different irradiation times. The observed results show significant changes with exposure time or total dosage received. An increased deviation from ideal diode conditions (7.2 to 18.0) was observed when they were bombarded with alpha particles for up to 40 min. Using the conventional technique, barrier height values were observed to generally increase after 2, 6, 10, 20 and 30 min of radiation. The same trend was seen in the values of the series resistance (0.5889-1.423 Ω for 2-8 min). These changes in the electronic properties of the DNA/Si junctions could therefore be utilized in the construction of sensitive alpha particle detectors.
许多类型的材料，如无机半导体，已被用作核辐射探测器。由于近期的核灾难，其重要性显著增加。尽管这类材料有许多优点，但测量细胞或生物对辐射的直接反应的能力可能会提高探测器的灵敏度。在这种背景下，近年来对脱氧核糖核酸（DNA）等半导体有机材料进行了研究。这是通过研究DNA与金属或半导体结在受到辐射时变化的电子特性而确定的。在这项工作中，我们利用铝（Al）/DNA/硅（Si）整流结在受到α辐射时的电流-电压（I-V）特性来研究其电子学。针对不同的辐照时间确定了理想因子、势垒高度和串联电阻等二极管参数。观察到的结果表明，随着暴露时间或接受的总剂量的变化，有显著变化。当用α粒子轰击长达40分钟时，观察到与理想二极管条件的偏差增大（从7.2到18.0）。使用传统技术，在辐射2、6、10、20和30分钟后，势垒高度值通常会增加。串联电阻的值也呈现相同趋势（2至8分钟时为0.5889 - 1.423Ω）。因此，DNA/硅结电子特性的这些变化可用于构建灵敏的α粒子探测器。
