In FIG. 2C, a doped amorphous layer 230 is formed over fin structure 220. Doped amorphous layer 230 includes a material having a non-crystalline structure (in other words, a material having a disordered atomic structure). In some implementations, doped amorphous layer 230 and fin structure 220 include the same material, but with different atomic structures. For example, doped amorphous layer 230 includes the same material as fin structure 210, except the material has a non-crystalline structure. In the depicted embodiment, where fin structure 220 includes silicon in a crystalline structure, doped amorphous layer 230 includes silicon in a non-crystalline structure, such as amorphous silicon. Doped amorphous layer 230 may thus be referred to as a doped amorphous silicon layer. Alternatively, in some implementations, doped amorphous layer 230 and fin structure include different materials with different atomic structures. For example, fin structure 220 includes a semiconductor material, such as silicon germanium, and doped amorphous layer 230 includes silicon in a non-crystalline form, such as amorphous silicon. Depending on design requirements of FinFET device 200, doped amorphous layer 230 includes n-type dopants, p-type dopants, or combinations thereof. Where FinFET device 200 is configured as a p-type FinFET device, doped amorphous layer 230 includes p-type dopants, such as boron, germanium, indium, other p-type dopant, or combinations thereof. Where FinFET device 200 is configured as an n-type FinFET device, doped amorphous layer 230 includes n-type dopants, such as arsenic, phosphorus, other n-type dopant, or combinations thereof. In some implementations, doped amorphous layer 230 is heavily doped with a dopant having a dopant concentration in a range from about 1×10²¹ dopants/cm³ (cm^?3) to about 4×10²¹ cm^?3. In some implementations, doped amorphous layer 230 has a higher dopant concentration than fin structure 220. For example, doped amorphous layer 230 may have a dopant concentration in a range from about 1×10²¹ cm^?3 to about 4×10²¹ cm^?3, while fin structure 220 may have a dopant concentration in a range from about 1×10¹⁰ cm^?3 to about 1×10¹⁸ cm^?3 (in some implementations, fin structure 220 is considered undoped or intrinsic at or below such doping concentrations).