Question

The process of extension of a single-crystal surface by growing a film in such a way that the added atoms form a continuation of the single-crystal structure is called :

• A. Ion implantation
• B. Chemical vapor deposition
• C. Electroplating
• D. Epitaxy

Hint:

Epitaxy: \[ \text{Single crystal grows on another single crystal maintaining lattice orientation} \]

Answer 1

The Correct Option is D

Concept: In semiconductor fabrication, epitaxy refers to the controlled growth of a crystalline layer on a crystalline substrate such that the deposited layer follows the crystal orientation of the substrate.

Step 1: Understand crystal continuation. The question states:
• Added atoms continue the original crystal structure.
• Newly grown layer aligns perfectly with substrate lattice. This is the defining feature of: \[ \text{Epitaxial growth} \]

Step 2: Define epitaxy. Epitaxy means: \[ \text{Ordered crystal growth on a crystalline substrate} \] The deposited layer:
• Maintains same lattice orientation
• Preserves crystal continuity Applications:
• IC fabrication
• High-speed devices
• Semiconductor wafers

Step 3: Analyze other options. Ion implantation Used for doping semiconductor using energetic ions. Not crystal continuation growth. Chemical vapor deposition CVD deposits films chemically but does not necessarily preserve single-crystal continuity. Electroplating Electrochemical metal coating process. Not related to epitaxial crystal growth.

Step 4: Write final answer. Hence the correct answer is: \[ \boxed{\text{Epitaxy}} \]