Semiconductor package and method of production thereof

Abstract

A semiconductor package of superior high frequency characteristics enabling easy mounting of a large-sized capacitor and thereby enabling fluctuation of the power supply voltage to be suppressed and enabling a reduction of the inductance of the wiring portion connecting the capacitor and a connection terminal, that is, a semiconductor package mounting a capacitor for suppressing fluctuation of a power supply voltage, wherein the capacitor is comprised of, in an attachment hole passing through the board in the thickness direction, a conductor wire to be connected to a connection terminal of a semiconductor chip at one end, a high dielectric constant material covering the conductor wire at a predetermined thickness, and a conductor layer arranged between the outer circumference of the high dielectric constant material and the inner wall of the attachment hole, provided as a coaxial structure having the conductor wire at its center, and a method of production of the same.

What is claimed is:  
     
         1 . A semiconductor package mounting a capacitor for suppressing fluctuation of a power supply voltage, wherein the capacitor is comprised of, in an attachment hole passing through the board in the thickness direction, a conductor wire to be connected to a connection terminal of a semiconductor chip at one end, a high dielectric constant material covering the conductor wire at a predetermined thickness, and a conductor layer arranged between the outer circumference of the high dielectric constant material and the inner wall of the attachment hole, provided as a coaxial structure having the conductor wire as its center.  
     
     
         2 . A semiconductor package as set forth in  claim 1 , wherein at least one of the signal wires provided at said board is comprised of, in an attachment hole passing through said board in a thickness direction, a signal wire at the core, a low dielectric constant material, and a conductor layer, formed as a coaxial wire matching the impedance.  
     
     
         3 . A method of production of a semiconductor package mounting a capacitor for suppressing fluctuation of a power supply voltage, comprising: 
 providing an attachment hole passing through a board in a thickness direction and    press-fitting into said attachment hole a capacitor cable comprised of a conductor wire at the core, a high dielectric constant material coaxially covering the conductor wire at a predetermined thickness, and a conductor sheath covering the outer circumference of the high dielectric constant material so as to attach the capacitor to said board.    
     
     
         4 . A method of production of a semiconductor package mounting a capacitor for suppressing fluctuation of a power supply voltage, comprising: 
 providing an attachment hole passing through a board in a thickness direction,    forming a conductor layer at an inner wall of said attachment hole, and    press-fitting into said attachment hole formed with said conductor layer a capacitor cable comprised of a conductor wire at the core and a high dielectric constant material coaxially covering the conductor wire at a predetermined thickness so as to attach the capacitor to said board.