Abstract: This invention provides a substrate structure that can effectively prevent scattering of solder balls which are produced due to explosion attributable to evaporation of flux during reflow soldering, and spreading of molten solder to the surroundings. On a substrate, a semiconductor chip is mounted via solder paste. The substrate is provided with a groove portion which continuously or discontinuously surrounds the solder paste.

Abstract: This invention provides a substrate structure that can effectively prevent scattering of solder balls which are produced due to explosion attributable to evaporation of flux during reflow soldering, and spreading of molten solder to the surroundings. On a substrate, a semiconductor chip is mounted via solder paste. The substrate is provided with a groove portion which continuously or discontinuously surrounds the solder paste.

Abstract: A power module structure has a heat plate for contacting a heat sink, an insulating plate soldered to the heat plate, a terminal soldered to the insulating plate and a semiconductor chip having a contact point corresponding to the terminal so as to contact the terminal through this contact point. The terminal is provided with a shock absorbing part that serves to weaken the force generated due to the difference in coefficient of thermal expansion between the terminal and the insulating plate. The terminal has a force restricting part that serves to restrict this force and is locally formed as a soldering area through which the terminal is soldered to the insulating plate. Such a structure is contained inside a base and makes a surface-contact with a heat sink to form a solid state relay.

Abstract: A power module structure has a heat plate for contacting a heat sink, an insulating plate soldered to the heat plate, a terminal soldered to the insulating plate and a semiconductor chip having a contact point corresponding to the terminal so as to contact the terminal through this contact point. The terminal is provided with a shock absorbing part that serves to weaken the force generated due to the difference in coefficient of thermal expansion between the terminal and the insulating plate. The terminal has a force restricting part that serves to restrict this force and is locally formed as a soldering area through which the terminal is soldered to the insulating plate. Such a structure is contained inside a base and makes a surface-contact with a heat sink to form a solid state relay.

Abstract: A solid state relay prevents the damage to photothyristor couplers when their performance characteristics vary slightly and enables phase angle control of an AC power supply using a less costly configuration than relays with photothyristor couplers having zero-crossing functions. The solid state relay includes a pair of input terminals configured to receive a control signal, a pair of output terminals configured to be connected to an AC power supply, a thyristor in parallel to the pair of output terminals configured to switch the AC power supply in response to the control signal. The solid state relay further includes two photothyristor couplers, each having a photothyristor, that are connected in series at a midpoint connection. The two photothyristor couplers are connected in parallel to the thyristor and are configured to control the thyristor. The solid state relay further includes two surge arresters connected in series at a midpoint connection that is connected to the photothyristor midpoint connection.