A method of forming substrates, e.g., silicon on insulator, silicon on
silicon. The method includes providing a donor substrate, e.g., silicon
wafer. The method also includes forming a cleave layer on the donor
substrate that contains the cleave plane, the plane of eventual
separation. In a specific embodiment, the cleave layer comprising silicon
germanium. The method also includes forming a device layer (e.g.,
epitaxial silicon) on the cleave layer. The method also includes
introducing particles into the cleave layer to add stress in the cleave
layer. The particles within the cleave layer are then redistributed to
form a high concentration region of the particles in the vicinity of the
cleave plane, where the redistribution of the particles is carried out in
a manner substantially free from microbubble or microcavity formation of
the particles in the cleave plane. That is, the particles are generally
at a low dose, which is defined herein as a lack of microbubble or
microcavity formation in the cleave plane. The method also includes
providing selected energy to the donor substrate to cleave the device
layer from the cleave layer at the cleave plane, whereupon the selected
energy is applied to create a controlled cleaving action to remove the
device layer from a portion of the cleave layer in a controlled manner.