Wurtzite-zincblende superlattices in InAs nanowires using a supply interruption method

Area of Science:

• Materials Science
• Nanotechnology
• Semiconductor Physics

Background:

• Crystal phase control is crucial for tuning semiconductor properties.
• Conventional bandgap engineering in single material systems has limitations.
• Precise control over crystal phases in nanowires is an emerging challenge.

Purpose of the Study:

• To investigate a supply interruption method for crystal phase control in single III-V semiconductor nanowires.
• To demonstrate the on-demand insertion of wurtzite segments into zincblende nanowires.
• To analyze the characteristics of the interfaces between different crystal phases.

Main Methods:

• Growth of single III-V semiconductor nanowires using metalorganic vapor phase epitaxy (MOVPE).
• Utilizing gold particles as seeds for nanowire growth.
• Analysis of nanowire crystal structure using transmission electron microscopy (TEM).
• Implementation of a supply interruption technique during MOVPE growth.

Main Results:

• Controlled insertion of wurtzite segments into pure InAs zincblende nanowires.
• Achieved controlled length and position of wurtzite segments.
• Demonstrated atomically sharp interfaces between wurtzite and zincblende segments.
• Fabricated segments with thicknesses of only a few bilayers.

Conclusions:

• The supply interruption method offers precise crystal phase control in single nanowires.
• This technique enables the engineering of complex heterostructures within nanowires.
• The method shows potential for advanced semiconductor device applications.