It is frequently desirable to form semiconductive materials having roughened outer surfaces. An exemplary semiconductive material with a roughened outer surface is hemispherical grain (HSG) polycrystalline silicon. Such material is utilized in constructions wherein it is desirable to have an extensive surface area. An exemplary construction is a capacitor electrode. Specifically, one way of increasing the total charge that can be stored by a capacitor without increasing the wafer real estate consumed by the capacitor is to increase the surface area of the capacitor's electrodes.
A difficulty in forming hemispherical grain polysilicon is in controlling a rate and amount of growth of the hemispherical grains. Problems associated with poor control of grain growth are (1) too little grain growth produces less than a desired available surface area; (2) too large of grains formed within a container capacitor can overfill the container; and (3) too much grain growth on outer surfaces of adjacent capacitors can lead to shorting between the capacitors. In light of such difficulties, it would be advantageous to develop new methods of forming semiconductive materials having roughened outer surfaces. Particularly, it would be advantageous to develop new methods of forming polycrystalline silicon materials having roughened outer surfaces.