Economical silicon-on-silicon hybrid wafer assembly

DETAILED DESCRIPTION According to the present invention, a technique for applying a thin film of material to a target wafer is provided.
This technique separates thin films of material from a high-quality donor substrate by implanting particles, such as hydrogen ions, into the donor substrate, and then separating a thin film of the high-quality material above the layer of implanted particles.
The thin film can be bonded to a lower-quality target wafer that provides mechanical support to form an economical hybrid substrate.
In a specific embodiment, the present invention provides a process for forming a film of material from a high-quality donor substrate using a controlled cleaving process.
That process includes a step of introducing energetic particles (e.
g.
, charged or neutral molecules, atoms, or electrons having sufficient kinetic energy) through a surface of a donor substrate to a selected depth underneath the surface, where the particles are at a relatively high concentration to define a thickness of donor substrate material (e.
g.
, thin film of detachable material) above the selected depth.
The surface of the donor wafer is then attached to a target wafer using, a low-temperature bonding process to form an intermediate substrate assembly.
The target wafer can be a single crystal, polycrystalline, or amorphous silicon substrate.
Energy is applied to a selected region of the donor substrate material to initiate a controlled cleaving action in the donor substrate, whereupon the cleaving action is made using a propagating cleave front(s) to free the donor material, which adheres to the target wafer, from a remaining portion of the donor substrate.
The thin film is then permanently bonded to the target wafer, typically with a high-temperature annealing process to form a hybrid silicon wafer suitable for integrated circuit fabrication, among other uses.
The lower-cost, lower-quality target wafer portion of the hybrid silicon wafer provides the mechanical support for the hybrid wafer, while the thin film portion of the hybrid wafer provides a high-quality material for the formation of electronic devices