Indy Irad LPCVD Vertical

The Tokyo Electron Indy Irad LPCVD Vertical is a specific model of vertical LPCVD furnace manufactured by Tokyo Electron. The machine is designed for low pressure chemical vapor deposition of thin films on semiconductor wafers.^[1]

In a vertical LPCVD furnace, wafer boats are loaded onto an elevator mechanism and raised into a vertically oriented heated quartz tube. The tube is evacuated to low pressure using a vacuum pump system, and process gases are introduced through injectors at controlled flow rates. Elevated temperatures cause chemical reactions on the wafer surfaces that deposit solid thin films while volatile byproducts are removed by the vacuum.

Temperature is precisely controlled in multiple zones along the tube length to achieve uniform film deposition across all wafers in the batch. The vertical orientation minimizes particle contamination by reducing turbulence and helps maintain consistent gas flow dynamics.

Primary applications include deposition of silicon nitride for sidewall spacers, passivation layers, and etch stop films; polysilicon deposition for gate electrodes and capacitors; and silicon dioxide deposition for interlayer dielectrics and isolation structures.

Vertical LPCVD furnaces are also used for doped film deposition by incorporating dopant gases such as phosphine or diborane into the process chemistry. The uniform thermal and gas distribution of these furnaces enables tight film thickness and resistivity control across the batch.