Numerical comparisons of the operational degradation of ferroelectric field-effect transistors using Hf–Zr–O thin films by charge pumping technique

Autor: Sung-Min Yoon, Seung Eon Moon, Dae-Hong Min, Tae-Hyun Ryu
Rok vydání: 2021
Předmět:
Zdroj: Journal of Physics D: Applied Physics. 54:315103
ISSN: 1361-6463
0022-3727
DOI: 10.1088/1361-6463/abfd6d
Popis: It is a crucial issue to accurately evaluate the device performance of the ferroelectric field-effect transistors (FeFETs) from a viewpoint of interface quality within the gate stack. A measurement scheme was composed of pulse configurations designed to avoid the dynamic changes in threshold voltage of the FeFET during the charge pumping (CP) measurements. Three types of control devices experiencing different levels of bias stress were prepared for investigations on the degradation origins of device performance. The frequency dependences of applied voltage levels to induce the variations in CP current (ICP) were suggested to result from the charge-injection events into the deteriorated interface trap sites. These behaviors were also verified by the pulsed current-voltage (I-V) method using high frequency gate voltage (VGS). The frequency dispersions of memory window (MW) variations and their VGS-sweep polarity dependences well reflected the interfacial behaviors related to the charge injection for the stressed devices. The trap/detrap times and locations of trapped charges could be examined by energy distribution of trap sites calculated by obtained ICP values. Thus, the MW obtained from the FeFET should be accurately analyzed to separate the charge-injection components from ferroelectric field effect by means of proposed useful guidelines using the CP and pulsed I-V methods.
Databáze: OpenAIRE
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