What is LOCOS?
A method that isolates devices by thickly oxidizing only areas not covered by nitride. It forms a beak-like encroachment at the edges (the bird's beak) and has been replaced by STI.
Field: Oxidation and diffusion
LOCOS in the explanations
In LOCOS, nitride-covered areas resist oxidation, but oxidant diffuses laterally through the pad oxide beneath the nitride edge, so oxide encroaches in a bird's-beak shape.
In LOCOS (local oxidation), what is the phenomenon called i…The earlier LOCOS approach suffered lateral bird's-beak encroachment that prevented narrow isolation and left surface steps, so STI replaced it around the 0.25 µm generation.
Which method is mainly used for device isolation in scaled …Thermal SiO2 is highly insulating and forms a high-quality interface with silicon, so it has served as the MOSFET gate dielectric, as device isolation (LOCOS and STI liners), as a mask for implantation and diffusion, and as a protective screen during implants.
Which is a typical use of thermally grown silicon oxide?
Questions that mention LOCOS (7)
- In LOCOS (local oxidation), what is the phenomenon called in which oxide encroaches like a bird's beak under the edge of the nitride mask?
- Which generally describes the thickness relationship between the field oxide used for isolation such as LOCOS and the gate oxide of a MOSFET?
- In LOCOS, what is the phenomenon called in which a thin nitride forms on the silicon surface under the nitride mask, later causing the gate oxide there to be locally thin or defective?
- Which method is mainly used for device isolation in scaled LSIs?
- Which is a typical use of thermally grown silicon oxide?
- Which correctly describes uses of silicon nitride (Si3N4) films?
- Which solution is commonly used for wet etching of silicon nitride?
Related terms
STI (shallow trench isolation) CMP Bird's beak Threshold voltage CVD FinFET Wet etching Selectivity 3D NAND Deal-Grove model