Non-volatile memory devices and methods of fabricating thereof are disclosed herein. An exemplary non-volatile memory device includes a heterostructure disposed over a substrate. A gate structure traverses the heterostructure, such that the gate structure separates a source region and a drain region of the heterostructure and a channel region is defined between the source region and the drain region. The non-volatile memory device further includes a nanocrystal floating gate disposed in the channel region of the heterostructure between a first nanowire and a second nanowire. The first nanowire and the second nanowire extend between the source region and the drain region.