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A hexagonal (wurtzite) form of silicon.
Science (New York, N.Y.)
|September 24, 1976
Summary
A hexagonal form of silicon, analogous to wurtzite carbon, was discovered using X-ray diffraction. This novel silicon phase arises from internal stresses generated during the silicon nitride reaction process.
Area of Science:
- Materials Science
- Solid-State Physics
- Crystallography
Background:
- Silicon is typically known for its cubic diamond (zinc blende) crystal structure.
- The wurtzite crystal structure is common in other Group IV elements and compounds.
- Previous research has not widely reported or confirmed the existence of hexagonal silicon under typical conditions.
Purpose of the Study:
- To identify and characterize a previously unreported hexagonal (wurtzite) phase of silicon.
- To investigate the formation mechanism of this hexagonal silicon phase.
- To understand the role of reaction-induced stresses in phase formation.
Main Methods:
- X-ray diffraction (XRD) analysis was employed to identify crystalline phases.
- Samples of reaction-bonded silicon nitride containing unreacted silicon were examined.
- Microstructural analysis was performed to correlate phase presence with reaction conditions.
Main Results:
- The presence of a hexagonal (wurtzite) silicon phase was confirmed via X-ray diffraction.
- This hexagonal silicon phase was found within reaction-bonded silicon nitride samples.
- The formation of the hexagonal phase was directly linked to stresses induced by the nitridation reaction.
Conclusions:
- The existence of hexagonal (wurtzite) silicon has been experimentally verified.
- Internal stresses generated during the nitridation of silicon are responsible for the formation of this phase.
- This finding expands the known polymorphism of silicon and its potential under specific reaction conditions.
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