A semiconductor device according to some embodiments includes: a transfer substrate, a semiconductor layer, and an adhesive layer between the transfer substrate and the semiconductor layer. The adhesive layer includes a lower portion and first and second protrusions, and the semiconductor layer comprises an upper portion and first and second protrusions. The first and second protrusions of the adhesive layer are in contact with the upper portion of the semiconductor layer, the first and second protrusions of the semiconductor layer are in contact with the lower portion of the adhesive layer, the first protrusion of the adhesive layer is disposed between the first and second protrusions of the semiconductor layer, and the second protrusion of the semiconductor layer is disposed between the first and second protrusions of the semiconductor layer.

Chemical sensors, devices and systems including the same, and related methods are disclosed. In an embodiment, a medical device is included having a graphene varactor including a graphene layer and a self-assembled monolayer disposed on an outer surface of the graphene layer through non-covalent interactions between the self-assembled monolayer and a n-electron system of graphene. The self-assembled monolayer includes one or more pillarenes, substituted pillarenes, calixarenes, substituted calixarenes, peralkylated cyclodextrins, substituted peralkylated cyclodextrins, pyrenes, or substituted pyrenes, or derivatives of each. Other embodiments are also included.