One or more techniques or systems for controlling a profile of a surface of a semiconductor region are provided herein. In some embodiments, an etching to deposition (E/D) ratio is set to be less than one to form the region within the semiconductor. For example, when the E/D ratio is less than one, an etching rate is less than a deposition rate of the E/D ratio, thus ‘growing’ the region. In some embodiments, the E/D ratio is subsequently set to be greater than one. For example, when the E/D ratio is greater than one, the etching rate is greater than the deposition rate of the E/D ratio, thus ‘etching’ the region. In this manner, a smooth surface profile is provided for the region, at least because setting the E/D ratio to be greater than one enables etch back of at least a portion of the grown region.