Split gate embedded memory technology and method of manufacturing thereof

摘要

Semiconductor devices and methods for forming a semiconductor device are disclosed. The method includes providing a substrate prepared with a memory cell region. A first gate structure is formed on the memory cell region. An isolation layer is formed on the substrate and over the first gate structure. A second gate structure is formed adjacent to and separated from the first gate structure by the isolation layer. The first and second gate structures are processed to form at least one split gate structure with first and second adjacent gates. Asymmetrical source and drain regions are provided adjacent to first and second sides of the split gate structure.

主权项

1. A method for forming a semiconductor device comprising:
providing a substrate prepared with a memory cell region; forming a first gate structure on the memory cell region; forming an isolation layer on the substrate and over the first gate structure; forming a second gate structure, wherein the second gate structure is adjacent to and separated from the first gate structure by the isolation layer; processing the first and second gate structures to form at least one split gate structure with first and second adjacent gates; and providing asymmetrical source and drain regions adjacent to first and second sides of the split gate structure, wherein providing the asymmetrical source and drain regions comprises
forming at least one first lightly doped region in a region of the substrate adjacent to the first side of the split gate structure, andforming at least one second lightly doped region in a region of the substrate adjacent to the second side of the split gate structure, wherein the first and second lightly doped regions are formed at different depths from a top surface of the substrate.