The disclosed technology generally relates to integrated circuit devices having at least one transistor, and methods of fabricating the same. In one aspect, an integrated circuit device can be produced from a silicon substrate and can include at least one nano-ridge transistor formed from III-V semiconducting crystal portions. The III-V portions can be grown epitaxially from the silicon substrate using an intermediate portion which can be adapted to produce aspect ratio trapping. The nano-ridge transistor can have a reduced footprint on the silicon substrate, may be adapted for power RF applications, and can be combined with MOS or CMOS transistors within one and a same integrated circuit.