Abstract: A solder paste including a solder powder; and a flux including at least an activating agent, and acid anhydride obtained by a dehydration reaction of aliphatic carboxylic acid having up to seven carbon atoms. The solder paste provides excellent solderability, high corrosive resistance and a good shelf life, but not an offensive smell, during the soldering operation.

Abstract: First and second ball forming plates are prepared. The cavities of the first plate and the cavities of the second plate 20 are filled with solder paste, respectively. The first plate and the second plate are placed in a facing relationship to each other and heated to form metal balls each of which corresponds to the total metal components of the solder paste in one cavity of the first plate and one cavity in the second plate. The metal balls are formed in the cavities of the lower plate 10. The metal balls are transferred from the cavities of the first plate to a device on which bumps are to be formed.

Abstract: An inverter apparatus is provided such that it can limit the inrush current to a smoothing capacitor of a converter at the instant of connection to AC power line. The inverter apparatus comprises a converter (3); an inverter (4); a first smoothing capacitor (12) between positive and negative buses that connect the output of the converter and the inputs of the inverter; a first resistor (14) connected in either the positive or negative bus between the first smoothing capacitors (12) and the converter (3); and the first switch means (16) connected in parallel with the first resistor. A second smoothing capacitor (11) connected in series with a parallel circuit of a second resistor (13) and second switch means (15) is connected between the positive and negative buses between the converter (3) and the switch means (16).

Abstract: First and second ball forming plates are prepared. The cavities of the first plate and the cavities of the second plate 20 are filled with solder paste, respectively. The first plate and the second plate are placed in a facing relationship to each other and heated to form metal balls each of which corresponds to the total metal components of the solder paste in one cavity of the first plate and one cavity in the second plate. The metal balls are formed in the cavities of the lower plate 10. The metal balls are transferred from the cavities of the first plate to a device on which bumps are to be formed.

Abstract: It is an object of the present invention to provide a step-down DC/DC converter which is resistant to common-mode noise, there are no significant restrictions on a main transistor used, on its energizing circuit and the frequency of the on and off cycles of the main transistor, etc., and is capable of generating a low DC output voltage from a high DC input voltage.

Abstract: In an inverter driving method, a method of completing an initial charging of a capacitor without damaging an upper arm-side semiconductor switching element, even when ON-signal latch thereof occurs during the initial capacitor charging period, is provided. The method applies to driving an inverter having an output unit in which at least one circuit of a serial connection, which comprises a pair of series-connected and complementarily ON-OFF driven semiconductor switching elements that are connected between positive and negative poles of a first DC power source. In this method, the initial charging of a capacitor at the inverter starting time is done by driving the series-connected semiconductor switching elements using alternately repeating short-time ON-OFF operations.

Abstract: A method for fabricating solder bumps onto a semiconductor chip. A solder ball forming member having a flat surface and a plurality of cavities arranged on the flat surface in a predetermined pattern is prepared. The cavities are then filled with a solder paste, and the solder ball forming member is heated to a temperature higher than the melting point of the solder so that the molten solder powder in the solder paste form solder balls due to surface tension. The semiconductor chip is then moved toward the solder ball forming member to transfer the heated solder balls from the solder ball forming member to the semiconductor chip.

Abstract: A method for fabricating a semiconductor device using a solder ball forming plate having cavities. The plate is made from a silicon plate having a flat surface in a <110> crystallographic plane, and an orientation flat in a <1-11> crystallographic plane. The cavities are formed on the flat surface of the plate by etching, using a mask having openings in the shape of rhombus arranged such that one side of the rhombus is generally parallel to the <1-11> crystallographic plane. As a result, the cavities having wedge-shaped bottom are formed. The cavities are then filled with a solder paste and are heated to form solder balls in the cavities while the plate in an inclined position. The solder balls are then transferred from the plate to a semiconductor chip.

Abstract: A manufacturing apparatus which thermal design is easy, and which is small in size and light in weight is provided which is operated by a person in a micro-gravity environment. The manufacturing apparatus has a manufacturing unit having an operation side on which an operation is performed directly by the hand of an operator who faces the front of the facility, and a housing section for supporting the manufacturing unit slidably along the operation side and in such a manner as to be pulled out from the front of the apparatus to the outside. The manufacturing unit is housed with the operation side being vertical, and slides substantially horizontally. Also, an observation facility is disposed between two manufacturing unit housed in a constant-temperature tank so that the two facing sides of the member are observed simultaneously.

Abstract: An automatic locking retractor for a seat belt assembly, which comprises a housing having a shaft for webbing, a spring for urging the shaft in a predetermined direction to cause rewinding of the webbing, a rachet wheel integrally fixed to the shaft, a pawl for locking the rachet wheel in position, a diameter-sensing element capable of sensing the diameter of the webbing wound about the shaft, and a control member. The control member has a first leg on one end and a second leg on the other end and is fitted on the shaft to permit movement between a pair of stoppers and to permit frictional sliding when one of the stoppers is engaged and the shaft continues to rotate. The rachet wheel has teeth for engagement with the pawl and these teeth are arranged at an interval almost equal to the distance between the first and second leg of the control member.