Abstract: A circuit board having a substrate, a first metal layer, a second metal layer and a solder mask layer. The first metal layer and the second metal layer with unequal surface areas spacedly arranged on the substrate and respectively providing a first solderable region and a second solderable region with equal surface areas. The solder mask layer having an opening and covered on the substrate, the first metal layer and the second metal layer to expose the first solderable region and the second solderable region. Besides, the first metal layer further provides a window abutted to the first solderable region, and the opening exposes a first blank region and a second blank region. Thus, the problem of unequal solder regions due to offset of the solder mask layer can be avoided, and improving the yield rate of the fabrication process.

Abstract: A circuit board having a substrate, a first metal layer, a second metal layer and a solder mask layer. The first metal layer and the second metal layer with unequal surface areas spacedly arranged on the substrate and respectively providing a first solderable region and a second solderable region with equal surface areas. The solder mask layer having an opening and covered on the substrate, the first metal layer and the second metal layer to expose the first solderable region and the second solderable region. Besides, the first metal layer further provides a window abutted to the first solderable region, and the opening exposes a first blank region and a second blank region. Thus, the problem of unequal solder regions due to offset of the solder mask layer can be avoided, and improving the yield rate of the fabrication process.

Abstract: A stacked substrate module includes a first and a second substrate. The first substrate has several pads which extend respectively from a stacked area of the first substrate to the outside of the stacked area. The second substrate has several welding areas arranged on the outer lateral side thereof; each welding area extends respectively from the outer lateral side of the second substrate to an upper and a lower surface of the second substrate. The second substrate is stacked in the stacked area of the first substrate, wherein the lateral side of the second substrate is aligned to the edge of the stacked area of the first substrate. The aforementioned pads correspond to the welding areas respectively. It is suitable to position a solder paste between the pads and the welding areas which can be reflowed to connect the pads and the welding areas.

Abstract: A method for forming solder bodies on a substrate includes: positioning a first mask plate, which is formed with at least one first through-hole, on the substrate; filling the first through-hole with a first solder paste so as to form a first solder body on the substrate; positioning a second mask plate, which is formed with at least one second through-hole and at least one recess spaced apart from the second through-hole, on the substrate in such a manner that the first solder body is received in the recess; and filling the second through-hole with a second solder paste so as to form a second solder body on the substrate.

Abstract: A hot-bar head is adapted for soldering at least two flexible flat cables to a substrate. The hot-bar head includes a head body having a connecting portion that extends in a longitudinal direction, and at least two soldering portions, each of which extends from the connecting portion and has a blade edge adapted for contacting one of the flexible flat cables. Adjacent ones of the soldering portions are spaced apart from each other in the longitudinal direction.

Abstract: A method for forming solder bodies on a substrate includes: positioning a first mask plate, which is formed with at least one first through-hole, on the substrate; filling the first through-hole with a first solder paste so as to form a first solder body on the substrate; positioning a second mask plate, which is formed with at least one second through-hole and at least one recess spaced apart from the second through-hole, on the substrate in such a manner that the first solder body is received in the recess; and filling the second through-hole with a second solder paste so as to form a second solder body on the substrate.