Current channeling along extended defects during electroreduction of SrTiO₃

Area of Science:

• Materials Science
• Solid State Physics
• Device Physics

Background:

• Electroreduction experiments on metal oxides are crucial for understanding memristive devices.
• The role of extended defects, particularly dislocations, in this process remains under-explored.

Purpose of the Study:

• To investigate the influence of dislocations on the electroreduction of strontium titanate (SrTiO3).
• To elucidate the mechanisms by which dislocations affect memristive device behavior.

Main Methods:

• Utilized thermal microscopy to detect local Joule heating during electroreduction.
• Introduced dislocations mechanically via scratching and sawing in SrTiO3 samples.
• Analyzed material changes and defect evolution under electrical and thermal stress.

Main Results:

• Observed current channeling along dislocations in the initial electroreduction stage of SrTiO3.
• Prolonged degradation led to matrix electroreduction and diminished the initial dislocation influence.
• Identified hotspot formation at the anode due to stoichiometry polarization, inducing dislocation gliding and new dislocation evolution.

Conclusions:

• Dislocations significantly influence the electroreduction process in SrTiO3 memristive devices.
• Electrical and thermal stresses promote dislocation activity, impacting resistive switching.
• Dislocations are key factors in the performance and degradation of memristive devices.