Chemical vapor deposition apparatus having a gas diffusing nozzle designed to diffuse gas equally at all levels

摘要

A chemical vapor deposition apparatus includes a processing chamber formed by an external tube, and an internal tube installed inside the external tube, a wafer boat securable within the processing chamber, and a single gas diffusing nozzle extending vertically within the processing chamber. The gas diffusing nozzle includes an outer tubular member having a closed top end, a diaphragm dividing the interior of the tubular member into two regions disposed side by side, and columns of gas diffusing openings extending through the tubular member on opposite sides of the diaphragm, respectively. The gas infused through the gas diffusing nozzle is forced by the diaphragm to rise up one side region of the tubular member and then descend through the other side region. In this way, the gas is evenly distributed to the wafers situated in the boat. Accordingly, the reaction time necessary for the gas to form identical layers on the wafers is minimized, the quality and reliability of the wafers is improved, and the production rate is increased.