The present disclosure is directed to a lead frame including a die pad with cavities, and methods for attaching a semiconductor die to the lead frame. The cavities allow for additional adhesive to be formed on the die pad at the corners of the semiconductor die, and prevent the additional adhesive from overflowing on to active areas of the semiconductor die.

The present disclosure is directed to a lead frame including a die pad with cavities, and methods for attaching a semiconductor die to the lead frame. The cavities allow for additional adhesive to be formed on the die pad at the corners of the semiconductor die, and prevent the additional adhesive from overflowing on to active areas of the semiconductor die.

A method for forming an underfill structure and semiconductor packages including the underfill structure are disclosed. In an embodiment, the semiconductor package may include a package including an integrated circuit die; an interposer bonded to the integrated circuit die by a plurality of die connectors; and an encapsulant surrounding the integrated circuit die. The semiconductor package may further include a package substrate bonded to the interposer by a plurality of conductive connectors; a first underfill between the package and the package substrate, the first underfill having a first coefficient of thermal expansion (CTE); and a second underfill surrounding the first underfill, the second underfill having a second CTE less than the first CTE.

A method of selectively transferring micro devices from a donor substrate to contact pads on a receiver substrate. Micro devices being attached to a donor substrate with a donor force. The donor substrate and receiver substrate are aligned and brought together so that selected micro devices meet corresponding contact pads. A receiver force is generated to hold selected micro devices to the contact pads on the receiver substrate. The donor force is weakened and the substrates are moved apart leaving selected micro devices on the receiver substrate. Several methods of generating the receiver force are disclosed, including adhesive, mechanical and electrostatic techniques.

A printed structure comprises a device comprising device electrical contacts disposed on a common side of the device and a substrate non-native to the device comprising substrate electrical contacts disposed on a surface of the substrate. At least one of the substrate electrical contacts has a rounded shape. The device electrical contacts are in physical and electrical contact with corresponding substrate electrical contacts. The substrate electrical contacts can comprise a polymer core coated with a patterned contact electrical conductor on a surface of the polymer core. A method of making polymer cores comprising patterning a polymer on the substrate and reflowing the patterned polymer to form one or more rounded shapes of the polymer and coating and then patterning the one or more rounded shapes with a conductive material.

A semiconductor device assembly has a first substrate, a second substrate, and an anisotropic conductive film. The first substrate includes a first plurality of connectors. The second substrate includes a second plurality of connectors. The anisotropic conductive film is positioned between the first plurality of connectors and the second plurality of connectors. The anisotropic conductive film has an electrically insulative material and a plurality of interconnects laterally separated by the electrically insulative material. The plurality of interconnects forms electrically conductive channels extending from the first plurality of connectors to the second plurality of connectors. A method includes connecting the plurality of interconnects to the first plurality of connectors and the second plurality of connectors, such that the electrically conductive channels are operable to conduct electricity from the first substrate to the second substrate. The method may include passing electrical current through the plurality of interconnects.

A method for forming an underfill structure and semiconductor packages including the underfill structure are disclosed. In an embodiment, the semiconductor package may include a package including an integrated circuit die; an interposer bonded to the integrated circuit die by a plurality of die connectors; and an encapsulant surrounding the integrated circuit die. The semiconductor package may further include a package substrate bonded to the interposer by a plurality of conductive connectors; a first underfill between the package and the package substrate, the first underfill having a first coefficient of thermal expansion (CTE); and a second underfill surrounding the first underfill, the second underfill having a second CTE less than the first CTE.

A printed structure comprises a device comprising device electrical contacts disposed on a common side of the device and a substrate non-native to the device comprising substrate electrical contacts disposed on a surface of the substrate. At least one of the substrate electrical contacts has a rounded shape. The device electrical contacts are in physical and electrical contact with corresponding substrate electrical contacts. The substrate electrical contacts can comprise a polymer core coated with a patterned contact electrical conductor on a surface of the polymer core. A method of making polymer cores comprising patterning a polymer on the substrate and reflowing the patterned polymer to form one or more rounded shapes of the polymer and coating and then patterning the one or more rounded shapes with a conductive material.

This member connection method includes a printing step. In the printing step, a coating film-formed region in which the coating film is formed, and a coating film non-formed region in which the coating film is not formed are formed in the print pattern, and the coating film-formed region is divided into a plurality of concentric regions and a plurality of radial regions by means of a plurality of line-shaped regions provided so as to connect various points, which are separated apart from one another in the marginal part of the connection region.

A package includes an integrated circuit that includes at least one active area and at least one secondary device area, a support configured to support the integrated circuit, and a die attach material. The integrated circuit being mounted on the support using the die attach material and the die attach material including at least one channel configured to allow gases generated during curing of the die attach material to be released from the die attach material.