Abstract:
Microelectronic assemblies and methods for making the same are disclosed herein. In one embodiment, a method of forming a microelectronic assembly comprises: assembling first and second components (102, 128) to have first major surfaces (104, 130) of the first and second components (102, 128) facing one another and spaced apart from one another by a predetermined spacing, the first component (102) having first and second oppositely-facing major surfaces (104, 106), a first thickness extending in a first direction between the first and second major surfaces (104, 106), and a plurality of first metal connection elements (112) at the first major surface (104), the second component (128) having a plurality of second metal connection elements (132) at the first major surface (130) of the second component (128); and then plating (electroplating or electroless plating) a plurality of metal connector regions (146) each connecting and extending continuously between a respective first connection element (112) and a corresponding second connection element (132) opposite the respective first connection element (112) in the first direction. The first and second metal connection elements (112, 132) may comprise metal vias (116, 134) in the components (102, 128) or metal pads (118) at the surface of the components (102, 128), the metal vias (116, 134) or the metal pads (118) being covered by plated metal regions (114). A first seed layer (126) may be formed overlying the major surface of the first component (102) before the plating process, wherein uncovered portions of the first seed layer (126) are removed after plating the metal connector regions (146). Similarly, a second seed layer (144) may be formed overlying the major surface of the second component (128). A plurality of barrier regions (152) may overlie the sidewalls of at least one of the metal connector regions (146), the first plated metal regions (114) or the second plated metal regions. At least some corresponding first and second metal connection elements (112, 132) may optionally not share a common axis. At least some first and second surfaces (113, 131) of the first metal connection elements (112) and the respective second metal connection elements (132) connected thereto may optionally not be parallel to a common plane.
Abstract:
A 3D interconnect structure and method of manufacture are described in which a through-silicon vias (TSVs) and metal redistribution layers (RDLs) are formed using a dual damascene type process flow. A silicon nitride or silicon carbide passivation layer may be provided between the thinned device wafer back side and the RDLs to provide a hermetic barrier and etch stop layer during the process flow.
Abstract:
A method for rejoining an IC die (102), removed from an existing substrate (104), to a new substrate (106), is disclosed herein. In one embodiment, such a method includes grinding an existing substrate (104) from an IC die (102) to create a substantially planar surface exposing interconnects (202) and surrounding underfill material (204). A new substrate (106) is provided having electrically conductive pedestals (300) protruding therefrom. The electrically conductive pedestals (300) are positioned to align with the exposed interconnects (202) and have a melting point substantially higher than the melting point of the interconnects (202). The method places the exposed interconnects (202) in contact with the electrically conductive pedestals (300). The method then applies a reflow process to melt and electrically join the exposed interconnects (202) with the electrically conductive pedestals (300). A structure produced by the method is also disclosed.
Abstract:
A method of making an electronic device which in one embodiment comprises providing a substrate, electrolessly depositing a barrier metal at least on portions of the substrate, and using wet chemistry such as electroless deposition to deposit a substantially gold-free wetting layer having solder wettability onto the barrier metal. An electronic device which in one embodiment comprises a metallization stack. The metallization stack comprises a barrier metal deposited electrolessly and a substantially gold-free wetting layer deposited on the barrier metal, and the wetting layer is wettable by solder.
Abstract:
According to an embodiment of the present invention, a method of stacking chips is provided. The method includes: providing a first substrate, wherein, on or within a surface of the first substrate, a first contact structure is arranged, wherein the first contact structure includes an intermediate layer and at least one contact for contacting the first substrate, the intermediate layer being provided on the surface of the first substrate and having at least one recess, the at least one recess accommodating or allowing access to the at least one contact; providing a second substrate, wherein on a surface of the second substrate, a second contact structure is arranged, the second contact structure having at least one contact; and inserting the second contact structure into the at least one recess of the intermediate layer.
Abstract:
Interconnect structures for stacked dies, including penetrating structures for through-silicon vias, and associated systems and methods are disclosed. A system in accordance with a particular embodiment includes a first semiconductor substrate having a first substrate material, and a penetrating structure carried by the first semiconductor substrate. The system further includes a second semiconductor substrate having a second substrate material with a preformed recess. The penetrating structure of the first semiconductor substrate is received in the recess of the second semiconductor substrate and is mechanically engaged with the recess and secured to the second semiconductor substrate.
Abstract:
A method forms a micropad (30, 70, 42) to an external contact (14, 54, 78) of a first semiconductor device (12, 52, 74). A stud (20, 24, 66, 88, 82) of copper is formed over the external contact. The stud extends above a surface of the first semiconductor device. The stud of copper is immersed in a solution of tin. The tin (28) replaces at least 95 percent of the copper of the stud and preferably more than 99 percent. The result is a tin micropad that has less than 5 percent copper by weight. Since the micropad is substantially pure tin, intermetallic bonds will not form during the time while the micropads of the first semiconductor device are not bonded. Smaller micropad dimensions result since intermetallic bonds do not form. When the first semiconductor device is bonded to an overlying second semiconductor device, the bond dimensions do not significantly increase the height of stacked chips.
Abstract:
A power MOSFET is provided on a semiconductor die to withstand radiation exposure. The semiconductor die is mounted on a die flag of a leadframe. The MOSFET includes a substrate and epitaxial layer formed over the substrate. A source region is formed in a surface of the semiconductor die. The source region is coupled to the die flag. A contact pad is formed on the source region. A base region is formed in the surface of the semiconductor die adjacent to the source region. The base region is electrically connected to the contact pad. A drain region is formed in the surface of the semiconductor die. The drain region is coupled to a first wire bond pad on the leadframe. A gate structure is formed over a channel between the source region and drain region. The gate structure is coupled to a second wire bond pad on the leadframe.