A semiconductor device and method of forming. The semiconductor device contains microelectronic components embedded in a single crystalline dielectric material. The method of forming a semiconductor device includes providing a single crystalline substrate, epitaxially depositing a single crystalline dielectric material on the single crystalline substrate, and forming microelectronic components in the single crystalline dielectric material. The single crystalline dielectric material can contain carbon with a diamond structure or hexagonal boron nitride (h-BN) with a graphene structure.