Microelectronic assembly with joined bond elements having lowered inductance

Abstract

First and second bond elements, e.g., wire bonds, electrically connect a chip contact with one or more substrate contacts of a substrate, and can be arranged so that the second bond element is joined to the first bond element at each end and so that the second bond element does not touch the chip contact or one or more substrate contacts. A third bond element can be joined to ends of the first and second bond elements. In one embodiment, a bond element can have a looped connection, having first and second ends joined at a first contact and a middle portion joined to a second contact.

1 . A method of making the microelectronic assembly, comprising:
 attaching a semiconductor chip to a dielectric element of a substrate, such that a plurality of chip contacts are exposed at a face of the chip;   forming first and second bond elements extending between a first chip contact of the chip and a first substrate contact at a face of the dielectric element,   wherein each of the first and second bond elements is a bond ribbon or a bond wire and provides parallel conductive paths between the first chip contact and the first substrate contact, the first bond element having a first end metallurgically joined to the first chip contact and a second end metallurgically joined to the first substrate contact, the second bond element being metallurgically joined to the first and second ends of the first bond element, and the second bond element does not touch the first chip contact and does not touch the first substrate contact.   
     
     
         2 . The method of  claim 1 , wherein the first electrically conductive bond element is a first bond wire and the second electrically conductive bond element is a second bond wire, the method including:
 forming the first bond wire having the first end metallurgically joined to the first chip contact and the second end metallurgically joined to the first substrate contact, and   then forming the second bond wire having a first end of the second bond wire metallurgically joined to the first end of the first bond wire and having a second end of the second bond wire metallurgically joined to the second end of the first bond wire.   
     
     
         3 . The method of  claim 2 , wherein the substrate overlies the face of the chip and has an opening exposing the plurality of chip contacts, wherein the first and second bond wires extend through the opening in the substrate. 
     
     
         4 . The method of  claim 2 , wherein the face of the chip faces away from the substrate, and the first and second bond wires extend beyond at least one edge of the chip. 
     
     
         5 . The method of  claim 2 , wherein one of the first and second ends of the first bond wire includes a ball, and the second bond wire includes a ball, wherein the ball of the second bond wire is metallurgically joined to the ball of the first bond wire. 
     
     
         6 . The method of  claim 2 , wherein one of the first and second ends of the first bond wire includes a ball, and the second bond wire includes a ball, wherein the ball of the second bond wire is metallurgically joined directly to an end of the first bond wire remote from the ball of the first bond wire. 
     
     
         7 . The method of  claim 2 , wherein one of the first and second ends of the first bond wire includes a ball, the second bond wire has a first end including a ball and a second end remote therefrom, the second end of the second bond wire being metallurgically joined to the ball of the first bond wire.