Conversion Pipe Geometry for Low-Stagnation Semiconductor Exhaust

The patent applies curvature by changing the pipe cross-section from a quadrangular shape to a circular shape. This curved geometry eliminates sharp corners where gas flow stagnation typically occurs, allowing smooth gas flow throughout the exhaust pipe. The circular cross-section ensures uniform flow distribution and prevents by-product accumulation, thereby reducing particle generation while maintaining manufacturing feasibility.

The patent segments the exhaust pipe into multiple sections: a first exhaust pipe with quadrangular cross-section for connection to the reaction chamber, a second exhaust pipe with circular cross-section for reduced stagnation, and a conversion section that transitions between the two shapes. This segmentation allows each section to optimize for its specific function while the conversion section manages the geometric transition, balancing manufacturing simplicity with flow efficiency.

The patent addresses the shape transition challenge by extending the conversion section in the longitudinal dimension. The conversion section gradually transforms the cross-sectional geometry from quadrangular to circular along its length, using extended surface areas to accommodate the geometric transition. This dimensional approach allows smooth flow transition without creating sharp corners or abrupt changes that would cause stagnation.