A temporary fixing composition is provided that is used to temporarily fix a first bonding target material and a second bonding target material to each other before the two bonding target materials are bonded to each other. The temporary fixing composition contains a first organic component having a viscosity of less than 70 mPa.Math.s at 25° C. and a boiling point of 200° C. or lower and a second organic component having a viscosity of 70 mPa.Math.s or greater at 25° C. and a boiling point of 210° C. or higher. It is preferable that, when thermogravimetry-differential thermal analysis is performed under the conditions at a temperature increase rate of 10° C./min in a nitrogen atmosphere with a sample mass of 30 mg, the 95% mass reduction temperature is lower than 300° C.

A temporary fixing composition is provided that is used to temporarily fix a first bonding target material and a second bonding target material to each other before the two bonding target materials are bonded to each other. The temporary fixing composition contains a first organic component having a viscosity of less than 70 mPa.Math.s at 25° C. and a boiling point of 200° C. or lower and a second organic component having a viscosity of 70 mPa.Math.s or greater at 25° C. and a boiling point of 210° C. or higher. It is preferable that, when thermogravimetry-differential thermal analysis is performed under the conditions at a temperature increase rate of 10° C./min in a nitrogen atmosphere with a sample mass of 30 mg, the 95% mass reduction temperature is lower than 300° C.

Provided are a resin composition for encapsulation that is superior in high-temperature reverse bias test (HTRB test) reliability; and a semiconductor device. The resin composition for encapsulation is used to encapsulate a power semiconductor element made of Si, SiC, GaN, Ga.sub.2O.sub.3 or diamond, and a cured product of the resin composition for encapsulation has a dielectric tangent of not larger than 0.50 when measured at 150° C. and 0.1 Hz. The semiconductor device is such that a power semiconductor element made of Si, SiC, GaN, Ga.sub.2O.sub.3 or diamond is encapsulated by the cured product of the resin composition for encapsulation.

A method includes forming a solder layer on a surface of one or more chips. A lid is positioned over the solder layer on each of the one or more chips. Heat and pressure are applied to melt the solder layer and attach each lid to a corresponding solder layer. The solder layer has a thermal conductivity of ≥50 W/mK.

A method includes forming a solder layer on a surface of one or more chips. A lid is positioned over the solder layer on each of the one or more chips. Heat and pressure are applied to melt the solder layer and attach each lid to a corresponding solder layer. The solder layer has a thermal conductivity of ≥50 W/mK.

A dicing die attach film including a dicing film and a die attach film laminated on the dicing film, in which the die attach film has an arithmetic average roughness Ra1 of from 0.05 to 2.50 μm at a surface in contact with the dicing film, and a value of ratio of Ra1 to an arithmetic average roughness Ra2 at a surface that is of the die attach film and is opposite to the surface in contact with the dicing film is from 1.05 to 28.00.

A dicing die attach film including a dicing film and a die attach film laminated on the dicing film, in which the die attach film has an arithmetic average roughness Ra1 of from 0.05 to 2.50 μm at a surface in contact with the dicing film, and a value of ratio of Ra1 to an arithmetic average roughness Ra2 at a surface that is of the die attach film and is opposite to the surface in contact with the dicing film is from 1.05 to 28.00.

A method for forming a semiconductor structure includes receiving a first die having a first interconnect structure and a first bonding layer over the first interconnect structure, and a second die having a second interconnect structure and a second bonding layer over the second interconnect structure; forming a recess indenting into the first bonding layer; and forming a positioning member on the second bonding layer. The method further includes bonding the second die over the first die; and disposing the positioning member into the recess. The positioning member includes dielectric, is surrounded by the first bonding layer, and is isolated from the first interconnect structure and the second interconnect structure.

A method for forming a semiconductor structure includes receiving a first die having a first interconnect structure and a first bonding layer over the first interconnect structure, and a second die having a second interconnect structure and a second bonding layer over the second interconnect structure; forming a recess indenting into the first bonding layer; and forming a positioning member on the second bonding layer. The method further includes bonding the second die over the first die; and disposing the positioning member into the recess. The positioning member includes dielectric, is surrounded by the first bonding layer, and is isolated from the first interconnect structure and the second interconnect structure.

A semiconductor package includes: a first package substrate; a first semiconductor device mounted on the first package substrate; a second package substrate arranged on an upper part of the first semiconductor device; and a heat-dissipating material layer arranged between the first semiconductor device and the second package substrate and having a thermal conductivity of approximately 0.5 W/m.Math.K to approximately 20 W/m.Math.K, wherein the heat-dissipating material layer is in direct contact with an upper surface of the first semiconductor device and a conductor of the second package substrate.