Lányi S, Nádazdy V
Institute of Physics, SAS, Bratislava, Slovakia.
Ultramicroscopy. 2007 Oct;107(10-11):963-8. doi: 10.1016/j.ultramic.2007.04.014. Epub 2007 May 1.
The performance of a novel instrument, the Scanning Charge-Transient Microscope, is demonstrated by analysis of defect states in thin-film transistors fabricated in location-controlled single-grain crystallised amorphous silicon. In the instrument, the principle of Isothermal Charge-Transient Spectroscopy is implemented. Its heart is a sensitive charge-to-voltage converter. It integrates the minute charge emitted from traps, periodically filled by voltage pulses. The sensitivity of the converter is in the attocoulomb range. The frequency of filling pulses is swept from a few hundred kHz to tens of Hz and the charge transients are transformed into a spectrum by suitable sampling and integration. In contrast to earlier investigations of defects in micron-sized field effect transistors, the sensitivity of the instrument makes it possible to investigate the defects in simple capacitors without the need to make use of the gain of the transistor. Thus, it can be combined with a scanning force or tunnelling microscope and perform local analysis of selected areas of the sample.
通过对在位置控制的单晶化非晶硅中制造的薄膜晶体管中的缺陷态进行分析,展示了一种新型仪器——扫描电荷瞬态显微镜的性能。在该仪器中,实现了等温电荷瞬态光谱原理。其核心是一个灵敏的电荷 - 电压转换器。它对由电压脉冲周期性填充的陷阱所发射的微小电荷进行积分。该转换器的灵敏度处于阿托库仑范围。填充脉冲的频率从几百千赫兹扫描到几十赫兹,并且通过适当的采样和积分将电荷瞬态转换为光谱。与早期对微米级场效应晶体管中缺陷的研究不同,该仪器的灵敏度使得无需利用晶体管的增益就能够研究简单电容器中的缺陷。因此,它可以与扫描力显微镜或隧道显微镜相结合,对样品的选定区域进行局部分析。