A method of establishing conductive connections is disclosed. The method includes providing an integrated circuit die having a plurality of solder balls each of which has an oxide layer on an outer surface of the solder ball. The method also includes performing a heating process to heat at least the solder balls and applying a force causing each of a plurality of piercing bond structures on a substrate to pierce one of the solder balls and its associated oxide layer to thereby establish a conductive connection between the solder ball and the piercing bond structure.

A curable resin or adhesive composition includes at least one monomer, a photoinitiator capable of initiating polymerization of the monomer when exposed to light, and at least one energy converting material, preferably a phosphor, capable of producing light when exposed to radiation (typically X-rays). The material is particularly suitable for bonding components at ambient temperature in situations where the bond joint is not accessible to an external light source. An associated method includes: placing a polymerizable adhesive composition, including a photoinitiator and energy converting material, such as a down-converting phosphor, in contact with at least two components to be bonded to form an assembly; and, irradiating the assembly with radiation at a first wavelength, capable of conversion (down-conversion by the phosphor) to a second wavelength capable of activating the photoinitiator, to prepare items such as inkjet cartridges, wafer-to-wafer assemblies, semiconductors, integrated circuits, and the like.

A curable resin or adhesive composition includes at least one monomer, a photoinitiator capable of initiating polymerization of the monomer when exposed to light, and at least one energy converting material, preferably a phosphor, capable of producing light when exposed to radiation (typically X-rays). The material is particularly suitable for bonding components at ambient temperature in situations where the bond joint is not accessible to an external light source. An associated method includes: placing a polymerizable adhesive composition, including a photoinitiator and energy converting material, such as a down-converting phosphor, in contact with at least two components to be bonded to form an assembly; and, irradiating the assembly with radiation at a first wavelength, capable of conversion (down-conversion by the phosphor) to a second wavelength capable of activating the photoinitiator, to prepare items such as inkjet cartridges, wafer-to-wafer assemblies, semiconductors, integrated circuits, and the like.

In a wafer level chip scale package, a wafer level interconnect structure is formed on a dummy substrate with temperatures in excess of 200 C. First semiconductor die are mounted on the wafer level interconnect structure. The wafer level interconnect structure provides a complete electrical interconnect between the semiconductor die and one or more of the solder bumps according to the function of the semiconductor device. A second semiconductor die can be mounted to the first semiconductor die. A first encapsulant is formed over the semiconductor die. A second encapsulant is formed over the first encapsulant. The dummy substrate is removed. A first UBM is formed in electrical contact with the first conductive layer. Solder bumps are made in electrical contact with the first UBM. A second UBM is formed to electrically connect the semiconductor die to the wafer level interconnect structure.

A package structure includes a semiconductor substrate, an under bump metallurgy layer, and at least one bump. The under bump metallurgy layer is disposed on the semiconductor substrate. The bump is disposed on the under bump metallurgy layer, and the bump includes a first portion and a second portion under the first portion, wherein a top surface of the first portion of the bump includes a flat portion and a rounded portion.

Some embodiments of the present invention include apparatuses and methods relating to processing and packaging microelectronic devices that reduce stresses on and limit or eliminate crack propagation in the devices.

Methods and systems for low-force, low-temperature thermocompression bonding. The present application teaches new methods and structures for three-dimensional integrated circuits, in which cold thermocompression bonding is used to provide reliable bonding. To achieve this, reduction and passivation steps are preferably both used to reduce native oxide on the contact metals and to prevent reformation of native oxide, preferably using atmospheric plasma treatments. Preferably the physical compression height of the elements is set to be only enough to reliably achieve at least some compression of each bonding element pair, compensating for any lack of flatness. Preferably the thermocompression bonding is performed well below the melting point. This not only avoids the deformation of lower levels which is induced by reflow techniques, but also provides a steep relation of force versus z-axis travel, so that a drastically-increasing resistance to compression helps to regulate the degree of thermocompression.

Methods and systems for low-force, low-temperature thermocompression bonding. The present application teaches new methods and structures for three-dimensional integrated circuits, in which cold thermocompression bonding is used to provide reliable bonding. To achieve this, reduction and passivation steps are preferably both used to reduce native oxide on the contact metals and to prevent reformation of native oxide, preferably using atmospheric plasma treatments. Preferably the physical compression height of the elements is set to be only enough to reliably achieve at least some compression of each bonding element pair, compensating for any lack of flatness. Preferably the thermocompression bonding is performed well below the melting point. This not only avoids the deformation of lower levels which is induced by reflow techniques, but also provides a steep relation of force versus z-axis travel, so that a drastically-increasing resistance to compression helps to regulate the degree of thermocompression.

Methods and systems for low-force, low-temperature thermocompression bonding. The present application teaches new methods and structures for three-dimensional integrated circuits, in which cold thermocompression bonding is used to provide reliable bonding. To achieve this, reduction and passivation steps are preferably both used to reduce native oxide on the contact metals and to prevent reformation of native oxide, preferably using atmospheric plasma treatments. Preferably the physical compression height of the elements is set to be only enough to reliably achieve at least some compression of each bonding element pair, compensating for any lack of flatness. Preferably the thermocompression bonding is performed well below the melting point. This not only avoids the deformation of lower levels which is induced by reflow techniques, but also provides a steep relation of force versus z-axis travel, so that a drastically-increasing resistance to compression helps to regulate the degree of thermocompression.

Methods and systems for low-force, low-temperature thermocompression bonding. The present application teaches new methods and structures for three-dimensional integrated circuits, in which cold thermocompression bonding is used to provide reliable bonding. To achieve this, reduction and passivation steps are preferably both used to reduce native oxide on the contact metals and to prevent reformation of native oxide, preferably using atmospheric plasma treatments. Preferably the physical compression height of the elements is set to be only enough to reliably achieve at least some compression of each bonding element pair, compensating for any lack of flatness. Preferably the thermocompression bonding is performed well below the melting point. This not only avoids the deformation of lower levels which is induced by reflow techniques, but also provides a steep relation of force versus z-axis travel, so that a drastically-increasing resistance to compression helps to regulate the degree of thermocompression.