sti etch process flow

# STI Etch Process Flow

STI Etch Process Flow describes the sequence connecting pattern preparation, removal and verification.

## Follow the transitions

Each box marks a manufacturing purpose, not an executable recipe. Some integrations combine steps or move strip and clean operations. Endpoint, where used, must be qualified against feature clearing and underlayer loss.

## Integration context

Shallow trench isolation forms a trench in silicon, not merely a hole in oxide. PR pattern transfer first opens the hard-mask stack. Silicon etching establishes isolation geometry; later liner formation, dielectric fill and planarization complete the isolation structure.

## What to verify

Check trench depth, width, corner shape, mask loss and later fill quality.

Define the input surface and the acceptance criterion at each transition. A qualified transition must account for pattern density, wafer position and incoming-film variation; a nominal clearing time on one monitor does not establish the full operating window.

## Related terminology

sti etch process flow, STI etch. Short abbreviations are local process vocabulary and can have other meanings; use the full module name when searching.

## Source and scope

[Silicon and dielectric etch capabilities](https://www.nanofab.ualberta.ca/capabilities/plasma-etch/). The diagram is an original teaching schematic. Layer choices and process families describe an example rather than a universal manufacturing recipe.