An integrated circuit has a substrate, a circuit, a core structure, a first encapsulation layer, a second encapsulation layer, and an oxide layer. The circuit includes transistors with active regions developed on the substrate and a metal layer formed above the active regions to provide interconnections for the transistors. The core structure is formed above the metal layer. The first encapsulation layer covers the core structure, and it has a first thermal expansion coefficient. The second encapsulation layer covers the first encapsulation layer over the core structure, and it has a second thermal expansion coefficient that is different from the first thermal expansion coefficient. As a part of the stress relief structure, the oxide layer is formed above the second encapsulation layer. The oxide layer includes an oxide thickness sufficient to mitigate a thermal stress between the first and second encapsulation layers.

An integrated circuit has a substrate, a circuit, a core structure, a first encapsulation layer, a second encapsulation layer, and an oxide layer. The circuit includes transistors with active regions developed on the substrate and a metal layer formed above the active regions to provide interconnections for the transistors. The core structure is formed above the metal layer. The first encapsulation layer covers the core structure, and it has a first thermal expansion coefficient. The second encapsulation layer covers the first encapsulation layer over the core structure, and it has a second thermal expansion coefficient that is different from the first thermal expansion coefficient. As a part of the stress relief structure, the oxide layer is formed above the second encapsulation layer. The oxide layer includes an oxide thickness sufficient to mitigate a thermal stress between the first and second encapsulation layers.

A magnetic sensor that ensures the height of the yoke and that guides magnetic flux in the direction in which the magnetic field sensing film detects a magnetic field includes a first magnetic field detection element that has a first magnetic field sensing film that detects a magnetic field in a first direction, and a first yoke that includes a first portion that is located on a side of the first magnetic field sensing film with respect to the first direction, and a second portion that is in contact with the first portion in a direction that is orthogonal to the first direction. The average dimension of the second portion in the first direction is larger than the average dimension of the first portion in the first direction.

A magnetic sensor that ensures the height of the yoke and that guides magnetic flux in the direction in which the magnetic field sensing film detects a magnetic field includes a first magnetic field detection element that has a first magnetic field sensing film that detects a magnetic field in a first direction, and a first yoke that includes a first portion that is located on a side of the first magnetic field sensing film with respect to the first direction, and a second portion that is in contact with the first portion in a direction that is orthogonal to the first direction. The average dimension of the second portion in the first direction is larger than the average dimension of the first portion in the first direction.

A soft magnetic film iron core is provided, including an insulating substrate and a soft magnet. Multiple layers of hollowing-out grid networks stacked vertically are arranged in the soft magnet, and all grid cavities in the hollowing-out grid networks are filled with insulators, such that the micro-morphology of the film iron core is changed, and the film iron core presents a structure of multilayer staggered grid networks as a whole. The soft magnetic film iron core can be processed by the micro-electro-mechanical system (MEMS) process. The proposed preparation method for the soft magnetic film iron core adopts low-cost standard MEMS processes such as ultraviolet (UV) lithography, electroplating, and wet etching, which can realize standardized mass production of the iron core and reduce the processing cost. A sensor using the soft magnetic film iron core as a sensitive element is provided.

A soft magnetic film iron core is provided, including an insulating substrate and a soft magnet. Multiple layers of hollowing-out grid networks stacked vertically are arranged in the soft magnet, and all grid cavities in the hollowing-out grid networks are filled with insulators, such that the micro-morphology of the film iron core is changed, and the film iron core presents a structure of multilayer staggered grid networks as a whole. The soft magnetic film iron core can be processed by the micro-electro-mechanical system (MEMS) process. The proposed preparation method for the soft magnetic film iron core adopts low-cost standard MEMS processes such as ultraviolet (UV) lithography, electroplating, and wet etching, which can realize standardized mass production of the iron core and reduce the processing cost. A sensor using the soft magnetic film iron core as a sensitive element is provided.

A radio frequency (RF) weak magnetic field detection sensor includes a ferromagnetic core, a pickup coil disposed to surround the ferromagnetic core, a substrate that includes an opening, a core pad connected to the ferromagnetic core and a coil pad connected to the pickup coil, and an insulating tube interposed between the ferromagnetic core and the pickup coil. The insulating tube includes a bobbin around which the pickup coil is wound, and a core hole formed to pass through the bobbin and configured to accommodate the ferromagnetic core.

An integrated circuit has a substrate, a circuit, a core structure, a first encapsulation layer, a second encapsulation layer, and an oxide layer. The circuit includes transistors with active regions developed on the substrate and a metal layer formed above the active regions to provide interconnections for the transistors. The core structure is formed above the metal layer. The first encapsulation layer covers the core structure, and it has a first thermal expansion coefficient. The second encapsulation layer covers the first encapsulation layer over the core structure, and it has a second thermal expansion coefficient that is different from the first thermal expansion coefficient. As a part of the stress relief structure, the oxide layer is formed above the second encapsulation layer. The oxide layer includes an oxide thickness sufficient to mitigate a thermal stress between the first and second encapsulation layers.

An integrated circuit has a substrate, a circuit, a core structure, a first encapsulation layer, a second encapsulation layer, and an oxide layer. The circuit includes transistors with active regions developed on the substrate and a metal layer formed above the active regions to provide interconnections for the transistors. The core structure is formed above the metal layer. The first encapsulation layer covers the core structure, and it has a first thermal expansion coefficient. The second encapsulation layer covers the first encapsulation layer over the core structure, and it has a second thermal expansion coefficient that is different from the first thermal expansion coefficient. As a part of the stress relief structure, the oxide layer is formed above the second encapsulation layer. The oxide layer includes an oxide thickness sufficient to mitigate a thermal stress between the first and second encapsulation layers.

A magnetic sensor includes a magnetic field conversion unit, a magnetic field detection unit, and a magnetic film. The magnetic field conversion unit includes a yoke that receives an input magnetic field and generates an output magnetic field. The input magnetic field contains an input magnetic field component in a direction parallel to Z direction. The output magnetic field contains an output magnetic field component in a direction parallel to X direction. The magnetic field detection unit includes a magnetic detection element that receives the output magnetic field and generates a detection value corresponding to the output magnetic field component. The magnetic film absorbs part of magnetic flux resulting from a noise magnetic field, which is a magnetic field in a direction to which the magnetic detection element has sensitivity and which is other than the output magnetic field component.