A microelectronic unit can include a carrier structure having a front surface, a rear surface remote from the front surface, and a recess having an opening at the front surface and an inner surface located below the front surface of the carrier structure. The microelectronic unit can also include a microelectronic element having a top surface adjacent the inner surface, a bottom surface remote from the top surface, and a plurality of contacts at the top surface. The microelectronic unit can also include terminals electrically connected with the contacts of the microelectronic element. The terminals can be electrically insulated from the carrier structure. The microelectronic unit can also include a dielectric region contacting at least the bottom surface of the microelectronic element. The dielectric region can define a planar surface located coplanar with or above the front surface of the carrier structure.

Rigid-flex-type circuit-board structure and manufacturing method, in which a flexible membrane and a sacrificial-material piece are attached to an insulator membrane in the location of the flexible zone. An insulator layer, which encloses within itself a sacrificial-material piece is manufactured on the surface of the conductor membrane. The flexible zone is formed in such a way that an opening is made in the insulator layer, through which the sacrificial-material piece is removed. The flexible zone comprises at least part of the flexible membrane as well as conductors, which are manufactured by patterning the insulator membrane at a suitable stage in the method.

A method of fabricating a microelectronic unit includes providing a semiconductor element having a front surface and a rear surface remote from the front surface, forming at least one first opening extending from the rear surface partially through the semiconductor element towards the front surface by directing a jet of fine abrasive particles towards the semiconductor element, and forming at least one conductive contact and at least one conductive interconnect coupled thereto. The semiconductor element can include a plurality of active semiconductor devices therein. The semiconductor element can include a plurality of conductive pads exposed at the front surface. Each conductive interconnect can extend within one or more of the first openings and can be coupled directly or indirectly to at least one of the conductive pads. Each of the conductive contacts can be exposed at the rear surface of the semiconductor element for electrical connection to an external device.

A semiconductor device is made by providing a sacrificial substrate and depositing an adhesive layer over the sacrificial substrate. A first conductive layer is formed over the adhesive layer. A polymer pillar is formed over the first conductive layer. A second conductive layer is formed over the polymer pillar to create a conductive pillar with inner polymer core. A semiconductor die or component is mounted over the substrate. An encapsulant is deposited over the semiconductor die or component and around the conductive pillar. A first interconnect structure is formed over a first side of the encapsulant. The first interconnect structure is electrically connected to the conductive pillar. The sacrificial substrate and adhesive layers are removed. A second interconnect structure is formed over a second side of the encapsulant opposite the first interconnect structure. The second interconnect structure is electrically connected to the conductive pillar.

A microelectronic assembly is provided which includes a first element consisting essentially of at least one of semiconductor or inorganic dielectric material having a surface facing and attached to a major surface of a microelectronic element at which a plurality of conductive pads are exposed, the microelectronic element having active semiconductor devices therein. A first opening extends from an exposed surface of the first element towards the surface attached to the microelectronic element, and a second opening extends from the first opening to a first one of the conductive pads, wherein where the first and second openings meet, interior surfaces of the first and second openings extend at different angles relative to the major surface of the microelectronic element. A conductive element extends within the first and second openings and contacts the at least one conductive pad.

In a method of manufacturing a semiconductor device, a semiconductor chip has first and second pads, a passivation film formed such that respective parts of the first and second pads are exposed, a first surface-metal-layer provided on the part of the first pad and a part of the passivation film, and a second surface-metal-layer provided on the part of the second pad and another part of the passivation film. Respective wires are electrically connected to the first and second surface-metal-layers. The semiconductor chip and the respective wires are then sealed with a resin.