A method of forming a semiconductor structure is provided. Two wafers are first bonded by oxide bonding. Next, the thickness of a first wafer is reduced using an ion implantation and separation approach, and a second wafer is thinned by using a removal process. First devices are formed on the first wafer, and a carrier is then attached over the first wafer, and an alignment process is performed from the bottom of the second wafer to align active regions of the second wafer for placement of the second devices with active regions of the first wafer for placement of the first devices. The second devices are then formed in the active regions of the second wafer. Furthermore, a via structure is formed through the first wafer, the second wafer and the insulation layer therebetween to connect the first and second devices on the two sides of the insulation layer.

Methods for selective etching of one layer or material relative to another layer or material adjacent thereto. In an example, a SiGe layer is etched relative to or selective to another silicon containing layer which either contains no germanium or geranium in an amount less than that of the target layer.

A method for forming an epitaxial stack on a plurality of substrates comprises providing a plurality of substrates to a process chamber and executing deposition cycles, wherein each deposition cycle comprises a first deposition pulse and a second deposition pulse. The epitaxial stack comprises a first epitaxial layer stacked alternatingly and repeatedly with a second epitaxial layer, the second epitaxial layer being different from the first epitaxial layer. The first deposition pulse comprises a provision of a first reaction gas mixture to the process chamber, thereby forming the first epitaxial layer having a first native lattice parameter. The second deposition pulse comprises a provision of a second reaction gas mixture to the process chamber, thereby forming the second epitaxial layer having a second native lattice parameter, wherein the first native lattice parameter lies in a range within 1.5% larger than and 0.9% smaller than the second native lattice parameter.

A method of forming conductive member includes: forming, on substrate, first portion containing first element constituting the conductive member to be obtained and second element causing eutectic reaction with the first element, and second portion containing third element constituting intermetallic compound with the second element; crystallizing primary crystals of the first element by adjusting temperature of the substrate after bringing the first portion into liquid phase state; growing crystal grains of the first element by diffusing the second element from the first portion into the second portion to increase ratio of the first element in crystal state to the first and second elements in the liquid phase state in the first portion while maintaining the temperature of the substrate at the same temperature; and turning the first portion, after completing diffusion of the second element into the second portion, into the conductive member having crystal grains of the first element.

A method for fabricating a semiconductor device includes the steps of forming a gate structure on a substrate, forming recesses adjacent to two sides of the gate structure, forming a buffer layer in the recesses, forming a first linear bulk layer on the buffer layer, forming a second linear bulk layer on the first linear bulk layer, forming a bulk layer on the second linear bulk layer, and forming a cap layer on the bulk layer.

A wafer includes a buried substrate; a layer of silicon (100) disposed on the buried substrate and forming multiple U-shaped grooves, wherein each U-shaped groove comprises a bottom portion and silicon sidewalls (111) at an angle to the buried substrate; a buffer layer disposed within the multiple U-shaped grooves; and multiple gallium nitride (GaN)-based structures having vertical sidewalls disposed within and protruding above the multiple U-shaped grooves, the multiple GaN-based structures each including cubic gallium nitride (c-GaN) formed at merged growth fronts of hexagonal gallium nitride (h-GaN) that extend from the silicon sidewalls (111).

A semiconductor-on-insulator substrate for use in RF applications, such as a silicon-on-insulator substrate, comprises a semiconductor top layer, a buried oxide layer and a passivation layer over a support substrate. In addition, a penetration layer is provided between the passivation layer and the silicon support substrate to ensure sufficient high resistivity below RF features and avoid increased migration of dislocations in the support substrate. RF devices may be fabricated on and/or in such a semiconductor-on-insulator substrate.

A substrate processing method of processing a substrate having a base film includes a loading process of loading the substrate into a processing container, a first process of performing a first plasma process in a state where the loaded substrate is held at a first position by raising substrate support pins of a stage arranged in the processing container, and a second process of performing a second plasma process while holding the substrate at a second position by lowering the substrate support pins.