A method for forming an integrated circuit structure includes forming an insulation layer over at least a portion of a substrate; and forming a plurality of semiconductor pillars over a top surface of the insulation layer. The plurality of semiconductor pillars are horizontally spaced apart by multiple portions of the insulation layer. The plurality of semiconductor pillars are allocated in a periodic pattern.The method further includes epitaxially growing a III-V compound semiconductor film from top surfaces and sidewalls of the semiconductor pillars. In addition, also disclosed is growing aIII-V compound semiconductor from a trench filled with an intermediate layer.