FIELD OF TECHNOLOGY

The invention relates to a micron-scale monocrystal film.

BACKGROUND

Lithium tantalate/lithium niobate monocrystal film, which is prepared with a silicon material as substrate, can be used to produce filters, optical waveguide modulators, optical waveguide switches, spatial light modulators, optical frequency doublers, surface acoustic wave generators, infrared detectors, ferroelectric memory, etc., and can bring about great economic and social benefits.

SUMMARY

The invention provides a micron-scale monocrystal film including a micron monocrystal film layer and is capable of reducing acoustic wave loss and insertion loss of a filter.

According to an exemplary embodiment of the present invention, the micron-scale monocrystal film includes 1) a substrate layer and 2) a micron monocrystal film layer located on the substrate layer, wherein a transition layer may be interposed between the substrate layer and the micron monocrystal film layer. The transition layer may include a first transition layer disposed adjacent to the substrate layer and a second transition layer disposed adjacent to the micron monocrystal film layer, wherein the transition layer may include H and an element of at least one kind of plasma gas used during the plasma bonding of the substrate layer and micron monocrystal layer.

According to an exemplary embodiment of the present invention, the plasma gas may be at least one of Ar, O2, and N2.

According to an exemplary embodiment of the present invention, the micron monocrystal film layer may have a thickness ranging from 5 to 50 μm.

According to an exemplary embodiment of the present invention, the concentration of H in the transition layer may range from 1×1020to 1×1022atoms/cc. The concentration of H may have a maximum value in the transition layer, and from the position with the maximum value, the concentration of H may be gradually decreased toward the micron monocrystal film layer and substrate layer.

According to an exemplary embodiment of the present invention, the first and second transition layers may each have a thickness ranging from 0.5 to 10 nm.

According to an exemplary embodiment of the present invention, the thickness of the substrate layer may range from 0.1 to 1 mm.

According to an exemplary embodiment of the present invention, the micron monocrystal film layer may be a lithium niobate monocrystal film, lithium tantalate monocrystal film, or quartz monocrystal film.

According to an exemplary embodiment of the present invention, the substrate layer may be a silicon substrate, lithium niobate substrate, lithium tantalate substrate, quartz substrate, silicon carbide substrate, or sapphire substrate.

According to an exemplary embodiment of the present invention, the materials for forming the micron monocrystal film layer and substrate layer may be the same or different from each other.

According to an exemplary embodiment of the present invention, from the first transition layer to the second transition layer, the content of the element from the substrate layer may be gradually reduced, and the content of the element from the micron monocrystal film layer may be gradually increased.

According to an exemplary embodiment of the present invention, the micron monocrystal film layer may have a polished surface or a rough surface with micron- or sub-micron-scale roughness.

