학술논문

Degradation mechanism of amorphous IGZO-based bipolar metal-semiconductor-metal selectors
Document Type
Conference
Source
2022 IEEE International Reliability Physics Symposium (IRPS) Reliability Physics Symposium (IRPS), 2022 IEEE International. :P10-1-P10-5 Mar, 2022
Subject
Components, Circuits, Devices and Systems
Engineered Materials, Dielectrics and Plasmas
Engineering Profession
Degradation
Electric breakdown
Schottky barriers
Tunneling
Magnetic memory
Delays
Reliability
breakdown
cross-point memory array
IGZO
selector
STT-MRAM
Language
ISSN
1938-1891
Abstract
To enable high-density cross-point arrays of magnetic memory a suitable access device is necessary. A promising candidate for this role is a metal-semiconductor-metal (MSM) tunneling device. In this work, the operation of an ultrathin Pt\6nm a-IGZO\Pt stack as an MSM selector is discussed. The focus is given to understanding the breakdown mechanism at high current regime, which prevents it from reaching the target current density. The breakdown is preceded by a gradual degradation process, which is manifested as an increase in high-field current after prolonged stress. This effect is recoverable – current returns to original value after sufficient delay time. Based on these observations, we propose a mechanism, where increased high-field current can be explained as a decrease in Schottky barrier height arising from stress-induced increase in oxygen vacancies.