Abstract:
A solder paste composition used in a solder precoating method of forming solder bumps by forming a dam around electrodes on a substrate, filling a solder paste composition on the electrodes within opening parts surrounded by the dam, and heating the solder paste composition filled, so that solder is adhered to the surfaces of the electrodes. The solder paste composition contains solder powder, which is of a particle size distribution in which particles having a particle size of below 10 μm are present 16% or more, and a sum of the particles having a particle size of below 10 μm and particles having a particle size of 10 μm or more and below 20 μm is 90% or more. This enables to suppress occurrence of bump defects, and form solder bumps of a uniform height with a high yield by a solder precoating method using the dam.
Abstract:
A circuit device which enables easy formation of a connection part that connects wiring layers to each other, and a manufacturing method thereof are provided. In a method for manufacturing a hybrid integrated circuit device of the present invention, a first resin film is formed so as to cover a first wiring layer. Thereafter, a first through-hole is formed, which penetrates the first resin film and exposes the first wiring layer from a bottom thereof. Next, a second resin film is formed so as to fill up the first through-hole. Moreover, a second through-hole is formed in the second resin film buried in the first through-hole, and a connection part is formed.
Abstract:
Epoxy compositions exhibiting low viscosity in the uncured state and low coefficient of thermal expansion in the cured state are provided. Also provided are processes for making the epoxy compositions. The low dielectric constant compositions are well-suited for use in multi-layer printed circuit boards. The desired properties are achieved by employment of a bimodal distribution of nano-scale fillers in the epoxy compositions.
Abstract:
An interconnection substrate includes: an interconnection layer region where at least a first conductor layer and a second conductor layer are vertically stacked in that order on a substrate, with the first conductor layer and second conductor layer containing conductive particles and a binder, wherein the first conductor layer and second conductor layer stacked in the interconnection layer region have conductive particles different in average particle size from each other. As a result, only an intended region can have low resistance.
Abstract:
An electronic assembly includes a bare IC die or a leadless electronic component having at least one electrically conductive contact formed on a surface of the component and a leadframe or a substrate having at least one electrically conductive trace. The conductive contact of the component is electrically and mechanically coupled to the conductive trace with a solder joint. The solder joint includes a plurality of solid electrically conductive metal particles having a substantially spherical shape and a diameter ranging from about one mil to about ten mils.
Abstract:
In one embodiment, a method is provided. The method comprises filling a microvia formed in a bond pad with solder paste comprising solder balls of the first size; and coating the bond pad with solder paste comprising solder balls of the second size, wherein the second size is greater than the first size.
Abstract:
A solder paste for fabricating bumps includes a flux and metallic alloy powder. The metallic alloy powder includes a plurality of low eutectic metallic alloy granules, and the size of these metallic alloy granules is 20-60 nullm and the average size of the metallic granules is 35 nullm to 45 nullm.
Abstract:
The present invention relates to a bump formation method, comprising the steps of providing a mask, in which a plurality of openings have been formed corresponding to a plurality of electrode pads, to a substrate provided with this plurality of electrode pads, filling the openings with a solder paste, and heat treating the solder paste. The solder paste contains a solder powder. This solder powder is one that contains no more than 10 wt % particles whose diameter is greater than the thickness of the mask and no more than 1.5 times this thickness. Preferably, this solder powder is one that contains no more than 10 wt % particles whose diameter is greater than 40% of the diameter of the openings, or one that contains no more than 30 wt % particles whose diameter is 40 to 100% the thickness of the mask.
Abstract:
Spherical solder drops having precise and accurate shape are formed by an ejection device and solidified to form solder balls for making solder pastes. The diameters of the solidified solder balls are determined by an excitation signal applied to the ejection device and changes in the diameter of the orifice in the ejection device. A solder paste is produced by mixing solidified solder balls of a single diameter or a combination of several different diameters with a carrier.
Abstract:
The method for metallizing the surface of dielectric materials according to the invention comprises a first step wherein a metal powder, the size of the grains of which is comprised between 10 and 5000 nm, is deposited and then incorporated into the surface of the dielectric material. In a second step of the method, the dielectric material which is so impregnated with metal, is immersed into an autocatalytic bath to coat the impregnated zones of the material with a layer of the metal contained in the bath in a thickness which is proportional to the immersion time. This method enables to metallize materials such as oxides, polymers and composites containing these oxides and/or these polymers. The characteristics of the metal deposits are controlled, on the one hand, by the type of metal, and the size and the geometry of the metal powder grains and, on the other hand, by the type and the structure of the dielectric materials coated with these deposits.