生物驻极体载流子特性分析

ANALYSIS OF CHARGE CARRIERS IN BIOELECTRETS

对猪骨这一生物驻极体中的电荷载流子的特性进行了一些分析.结果表明.在正常状态下.动物骨骼内部的导电载流子主要来自于其胶原纤维和基质细胞中的水分子.这时用范畴堡尔法测得其霍尔系数为负值.具有N型半导体的一些特征.若对高温干燥处理后的猪骨进行测量.则观察到其霍尔系数的反向突变,显示出P型半导体的导电性.这一转变被解释为水分子的丧失使样品中的正离子导电从次要地位转变为主要地位,加热时样品中水分子的迁移过程会在短接的外电路中形成一方向恒定的负电流峰,对电流峰的计算表明,猪骨中负电荷的激活能为0.86eV左右.

In this paper, the properties of charge carriers in pig bone, a kind of bioelectrets, is analyzed.The results showed that conduction carriers in animal bones came mainly from water molecules bound in gelatin fibers and basal cells in general. The Hall coefficient measured by Van der Pauws method showed to be negative for virgin samples, which have some characteristics of a N- type semiconductor. If the measurement was carried out after the sample was dried under high temperature. the inverse transition of Hall coefficient was observed and the sample showed the conductive property of a P - type semiconductor. The transition is cxpalined as that the lose of water molecules makes the positive ions govern the conductive process. The thermally stimulated depolarizaion current (TSDC) spectrum of short circuit of sample was found to have a negative peak during the transport of water molecules. It was found that the exated energy of a negative charge in pig bone was around 0.86eV.