An electronic device includes a printed circuit board having a wall deposited directly on a board serving as a base for a printed circuit. As the board is constructed, the wall is deposited on the board for controlling airflow. The wall controls airflow across the board and around components mounted to the board. The wall may be utilized for controlling airflow in combination with a second printed circuit board positioned adjacent to the first printed circuit board. The wall may be utilized for controlling various types of airflow, including airflow from sources including fans and convection, and from geometries including horizontal and vertical mounting geometries. The silicon wall may be utilized for preventing heat airflow generated by heat radiated from one component from impinging upon another component.