A method for the formation of a thin optical crystal layer (e.g., a thin LiNbO.sub.3 optical single crystal layer) overlying a low dielectric constant substrate (e.g., a low dielectric constant glass substrate). The method includes implanting ions (e.g., He.sup.+) through a surface of an optical crystal substrate. The implanting of the ions defines, in the optical crystal substrate, a thin ion-implanted optical crystal layer overlying a bulk optical crystal substrate. A low dielectric constant substrate is subsequently bonded to the surface, using either a direct or an indirect bonding technique, to form a bonded structure. The bonded structure is thermally annealed at a temperature in the range of 300.degree. C. to 600.degree. C. for 30 minutes to 300 minutes. Thereafter, the thin ion-implanted optical crystal layer and low dielectric constant substrate are separated from the bulk optical crystal substrate using mechanical force applied to the low dielectric constant substrate and/or the bulk optical crystal substrate in the direction of separation. As a result, a thin optical crystal layer overlying a low dielectric constant substrate is formed. The thin optical crystal layer has characteristics (e.g., an electro-optical coefficient, surface quality and homogeneity) that are equivalent to the optical crystal substrate, from which it originated, and is thus suitable for use in electro-optical devices. Furthermore, the low dielectric constant substrate enables the manufacturing of electro-optical devices with a reduced RF and optical wave velocity mismatch, a broad bandwidth and a low modulation or switching voltage.
CROSS-REFERENCES TO RELATED APPLICATIONS
This application claims priority from co-pending U.S. Provisional Patent Application No. 60/242,401 filed Oct. 20, 2000 entitled A TECHNIQUE FOR FABRICATING HYBRID EO PHOTONIC INTEGRATED DEVICES AND CIRCUITS, which is hereby incorporated by reference, as if set forth in full in this document, for all purposes.
The present invention provides a bonding pad for an optical semiconductor device, including: a first supplementary adhesive layer made of Si.sub.3 N.sub.4, being formed on a semiconductor substrate; a bonding pad layer made of benzocyclobutene, being formed on the first supplementary adhesive layer; a second supplementary adhesive layer made of Si.sub.3 N.sub.4, being formed on the bonding pad layer; and a metallic electrode layer formed on the second supplementary adhesive layer.
A method of fabricating substrates while minimizing loss of starting material of an ingot, wherein a layer is transferred onto a support. The technique includes forming a flat front face on a raw ingot of material, implanting atomic species through the front face to a controlled mean implantation depth to create a zone of weakness that defines a top layer of the ingot, bonding a support to the front face of the ingot, wherein the support has a surface area that is smaller than a surface area of the front face of the ingot, and detaching from the ingot at the zone of weakness that portion of the top layer that is bonded to the support to form the substrate.
A BST microwave device includes a single crystal oxide wafer. A silicon dioxide layer is formed on the single crystal oxide layer. A silicon substrate is bonded on the silicon dioxide layer. A BST layer is formed on the single crystal oxide layer.
