Publications

Selective layer disordering in intersubband Al_0.028Ga_0.972 N/AlN superlattices with silicon nitride capping layer

Wierer Jr, Jonathan W.; Allerman, A.A.; Skogen, Erik J.; Tauke-Pedretti, Anna; Vawter, Gregory A.; Montano, Ines M.

We demonstrate the selective layer disordering in intersubband Al_0.028Ga_0.972 N/AlN superlattices using a silicon nitride (SiN_x) capping layer. The (SiN_x) capped superlattice exhibits suppressed layer disordering under high-temperature annealing. In addition, the rate of layer disordering is reduced with increased SiN_x thickness. The layer disordering is caused by Si diffusion, and the SiN_x layer inhibits vacancy formation at the crystal surface and ultimately, the movement of Al and Ga atoms across the heterointerfaces. In conclusion, patterning of the SiN_x layer results in selective layer disordering, an attractive method to integrate active and passive III–nitride-based intersubband devices.