Texas Instruments Corporation

Sohichi Kadoguchi

Norihiro Kawakami

Yoshikatsu Umeda

Margaret Simmons-Matthews

Akira Karashima

Methods and systems are disclosed for forming secure wirebonds between electrical contacts in electronic device assemblies. Representative embodiments of the invention are described for forming a wirebond including system components and method steps for generating electromagnetic energy from a heat source and transmitting heat to a ball formed on a bondwire. Subsequently, pressure applied to the ball at the bonding site is used in the formation of a wirebond.

Spot heat wirebonding

A semiconductor device with a chip having at least one metallic bond pad () over weak insulating material (). In contact with this bond pad is a flattened metal ball () made of at least 99.999% pure metal such as gold, copper, or silver. The diameter () of the flattened ball is less than or equal to the diameter () of the bond pad. A wire () is connected to the bond pad so that the wire has a thickened portion () conductively attached to the flattened metal ball. The wire is preferably made of composed metal such as gold alloy. The composition of the flattened ball is softer than the wire. This softness of the flattened ball protects the underlying insulator against damage caused by pressure or stress, when the composed ball is attached.

Wire bonds having pressure-absorbing balls

A semiconductor package according to the present invention includes a die attachment area for receiving a die attachment material and a stitch bond area for receiving a wire lead from a die. The stitch bond area is adjacent to said die attachment area on the substrate. Moreover, a stud bump is formed on the substrate for preventing the die attachment material from contacting the stitch bond area when a die is attached to the die attachment area. A method for manufacturing a semiconductor package according to the present invention also is disclosed.

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Beppu, Japan

Sohichi Kadoguchi