Abstract: A process for forming a plurality of bumps on a wafer comprises forming a first UBM (under ball metallurgy) over an active surface of a wafer. A second UBM is formed over the first UBM. A part of the second UBM is removed to expose the first UBM. A plurality of solders are respectively formed to cover the second UBM and the first UBM not covered by the second UBM. The first UBM not covered by the second UBM and not covered by the solders is removed.

Abstract: A method of forming a bump on an active surface of a wafer is disclosed. The method of the invention forms an under ball metallurgy (UBM) onto the active surface of the wafer. Then, the UBM is partially removed until a portion of the active surface of the wafer is exposed. At least one conductive stud is bonded onto the non-removed UBM by wire bonding.

Abstract: A method of forming bumps on the active surface of a silicon wafer. An under-ball metallic layer is formed over the active surface of the wafer. A plurality of first solder blocks is attached to the upper surface of the under-ball metallic layer. Each first solder block has an upper surface and a lower surface. The lower surface of each first solder block bonds with the under-ball metallic layer. The upper surfaces of the first solder blocks are planarized. A second solder block is attached to the upper surface of each first solder block and then a reflux operation is carried out.

Abstract: A process of forming bumps on conductive pads is provided. First, an adhesion layer made of titanium, titanium-wolfram alloy or chromium is formed on the conductive pads. Subsequently, a barrier layer made of nickel-vanadium alloy is formed on the adhesion layer. Next, a wettable layer made of copper is formed on the barrier layer. Subsequently, solder material is formed on the wettable layer. Subsequently, etching processes are performed to remove the wettable layer, the barrier layer and the adhesion layer that are exposed to the outside. The wettable layer, the barrier layer and the adhesion layer remain under the solder material. Afterward, a reflow process can be selectively performed.

Abstract: A method of forming bumps on the active surface of a silicon wafer. A first under-bump metallic layer is formed over the active surface of the wafer. A second under-bump metallic layer is formed over the first under-bump metallic layer. A portion of the second under-bump metallic layer is removed to expose the first under-bump metallic layer. A plurality of solder bumps is implanted onto the second under-bump metallic layer. The exposed first under-bump metallic layer is removed so that only the first under-bump metallic layer underneath the second under-bump metallic layer remains.

Abstract: A method for etching a nickel-vanadium alloy is described. The etching of the nickel-vanadium alloy is conducted using an etchant that comprises sulfuric acid. Further, the etching rate of the nickel-vanadium alloy is controlled based on the electrolytic reaction between the etchant and the nickel-vanadium alloy thin film.

Abstract: The present invention provides a bump fabrication process. A wafer is provided with a patterned photoresist layer formed on the wafer. The patterned photoresist layer has a plurality of openings, corresponding to bonding pads. A conductive layer is formed on the photoresist layer and the exposed bonding pads. Afterwards, a sticker film is provided to lift off the conductive layer on the photoresist layer, while the conductive layer within the openings is not removed. A solder paste is filled into the openings. A reflow step is performed to turn the filled solder paste into globular bumps. At last, the photoresist layer is removed.

Abstract: A chip scale package mainly comprises two elastomer pads respectively interposed between a substrate and a semiconductor chip. Each of the elastomer pads is respectively situated on the flank of a slot centrally defined in the substrate, and keeps a predetermined distance from the slot. The semiconductor chip is attached onto the upper surface of the substrate through the two elastomer pads wherein bonding pads formed on the semiconductor chip are exposed from the slot of the substrate. The upper surface of the substrate is provided with a plurality of solder pads and leads. Each of the leads has one end electrically connected to a corresponding solder pad, and the other end electrically connected to a corresponding bonding pad of the semiconductor chip. The substrate has a plurality of through-holes formed corresponding to the solder pads such that each solder pad has a portion exposed within the through-hole for mounting a solder ball.

Abstract: A chip scale package mainly comprises a semiconductor chip disposed on an upper surface of a substrate and sealed by a package body. The package body comprises a resin base material divided into a first region and a second region. The resin base material contains a plurality of filler particles having the percentage by weight of the filler particles in the first and second regions being different. Thus, in accordance with the present invention, the package provides better buffering effect for stresses due to CTE mismatch between the substrate and the chip, and significantly reduces the moisture from surrounding diffusing into the package thereby reducing the problems of delamination or die-cracking.

Abstract: A chip scale package mainly comprises two elastomer pads respectively interposed between a substrate and a semiconductor chip. Each of the elastomer pads is respectively situated on the flank of a slot centrally defined in the substrate, and keeps a predetermined distance from the slot. The semiconductor chip is attached onto the upper surface of the substrate through the two elastomer pads wherein bonding pads formed on the semiconductor chip are exposed from the slot of the substrate. The upper surface of the substrate is provided with a plurality of solder pads and leads. Each of the leads has one end electrically connected to a corresponding solder pad, and the other end electrically connected to a corresponding bonding pad of the semiconductor chip. The substrate has a plurality of through-holes formed corresponding to the solder pads such that each solder pad has a portion exposed within the through-hole for mounting a solder ball.