Stacking fault is a type of crystal defect found in materials like silicon where the normal sequence of atomic layers is disturbed.
What does that mean?
In a perfect crystal, atoms are arranged in a very regular, repeating pattern. For example, silicon atoms stack in a specific order of layers (often described as ABCABCABC…).
A stacking fault happens when this order is broken. For instance:
- Normal sequence: ABCABCABC
- With a stacking fault: ABCABABC
So one layer is either missing, misplaced, or repeated, disrupting the structure.
Why does it matter?
- It affects the electrical properties of silicon.
- It can reduce the performance of semiconductor devices.
- It often forms during crystal growth or processing.
Where does it occur?
Stacking faults in silicon typically occur along the {111} planes, which are the most densely packed atomic planes in the crystal.