A method includes bonding a first package component over a second package component, dispensing a first underfill between the first package component and the second package component, and bonding a third package component over the second package component. A second underfill is between the third package component and the second package component. The first underfill and the second underfill are different types of underfills.

A semiconductor device includes: a wiring board, a chip stack provided above the wiring board and including a first semiconductor chip; a second semiconductor chip provided between the wiring board and the first semiconductor chip; a first adhesive layer provided between the first semiconductor chip and the second semiconductor chip and on the second semiconductor chip; and a sealing insulation layer including a first part and a second part, the first part covering the chip stack, and the second part extending between the wiring board and the first semiconductor chip.

A method includes bonding a first package component over a second package component, dispensing a first underfill between the first package component and the second package component, and bonding a third package component over the second package component. A second underfill is between the third package component and the second package component. The first underfill and the second underfill are different types of underfills.

A semiconductor device includes: a wiring board, a chip stack provided above the wiring board and including a first semiconductor chip; a second semiconductor chip provided between the wiring board and the first semiconductor chip; a first adhesive layer provided between the first semiconductor chip and the second semiconductor chip and on the second semiconductor chip; and a sealing insulation layer including a first part and a second part, the first part covering the chip stack, and the second part extending between the wiring board and the first semiconductor chip.

A method includes bonding a first package component over a second package component, dispensing a first underfill between the first package component and the second package component, and bonding a third package component over the second package component. A second underfill is between the third package component and the second package component. The first underfill and the second underfill are different types of underfills.

A method includes bonding a first package component over a second package component, dispensing a first underfill between the first package component and the second package component, and bonding a third package component over the second package component. A second underfill is between the third package component and the second package component. The first underfill and the second underfill are different types of underfills.

A method includes bonding a first package component over a second package component, dispensing a first underfill between the first package component and the second package component, and bonding a third package component over the second package component. A second underfill is between the third package component and the second package component. The first underfill and the second underfill are different types of underfills.