latter in turn defines the size of the gold ball 120 formed by the spark from the torch 112 so it is the ascent or descent distance of the capillary 104 that defines the size of the bump 142 before bonding gold ball 120 consequently in the present embodiment the size of the gold ball 120 is controlled by the distance moved by the capillary 104 by this method a desired number of bumps can be formed sequentially for this for example the working stand 102 may be shifted after a desired number of bumps are formed as shown in fig3 b a leveling plate 114 is placed on these bumps 142 formed on the surface of the ic chip 14 to apply a leveling load so that all the bumps 142 formed on the surface of the ic chip 14 have the same specified height while details of the dimensions of the bump 142 will be given later here as described in the fourth aspect of the present invention u03c6a h and f are used to denote the top diameter of a bump bonded with an electrode the height of a bump defined as the distance from the semiconductor integrated circuit chip to the end of the bump bonded with an electrode and the linear thermal expansion coefficient of the sealing resin respectively in order for the dimensions of bumps 142 to be in the region defined by the above formula a it is desirable that each individual bump before bonding with an electrode 122 as illustrated in fig4 is.