Methods for manufacturing micromachined devices and the devices obtained are disclosed. In one embodiment, the method comprises providing a structural layer comprising an amorphous semiconductor material, forming a shielding layer on a first portion of the structural layer and leaving exposed a second portion of the structural layer, and annealing the second portion using a first fluence. The method further comprises removing the shielding layer, and annealing the first portion and the second portion using a second fluence that is less than half the first fluence. In an embodiment, the device comprises a substrate layer, an underlying layer formed on the substrate layer, and a sacrificial layer formed on only a portion of the underlying layer. The device further comprises a structural layer that is in contact with the underlying layer and comprises a first region annealed using a first fluence and a second region annealed using a second fluence.