A chuck vacuum line of a semiconductor processing tool includes a first portion that penetrates a sidewall of a main pumping line of the semiconductor processing tool. The chuck vacuum line includes a second portion that is substantially parallel to the sidewall of the main pumping line and to a direction of flow in the main pumping line. A size of the second portion increases between an inlet end of the second portion and an outlet end of the second portion along the direction of flow in the main pumping line.