Clip mount for integrated circuit leadframes
View Patent ↗A leadframe having a die thereon connects a high current conductive area on the die to a leadframe contact using a copper clip that include a structural portion that is received within a recess-like “tub” that is formed in the leadframe contact which tub is shaped to conform to the geometric shape of the clip. In the preferred embodiment, a leadframe structure fabricated by etching includes at least one contact that is a halfetch recess or “tub” that receives one end of the clip structure and is retained in the tub by an adhesive. The end of the clip that is received in the tub is held in place during subsequent handling until the clip and leadframe undergo solder reflow to effect an electrical connection sufficient to handle the current load and also effect a reliable mechanical connection.
1. A structural organization for electrically interconnecting a portion of a first semiconductor die to a leadframe electrically connected to a second portion of a second semiconductor die, comprising:
a first leadframe having a first die attached thereto and having a plurality of electrical contacts associated therewith,
a second leadframe having a second die attached thereto and having a plurality of electrical contacts associated therewith, said second leadframe having a thickness dimension associated therewith and having a recess-like tub formed therein; and
an electrically conductive clip having first and second portions, a one of said first and second portions electrically connected to a portion of the first die and the other of said first and second portions mechanically received within said tub of said second leadframe.
2. The structural organization of claim 1 , wherein said electrically conductive clip includes a columnar part received within the tub.
3. The structural organization of claim 2 , wherein said a columnar part has a width dimension W′ and a thickness dimension T′ and said tub has a dimension W corresponding to and larger than said width dimension W′ and a dimension corresponding to and larger said thickness dimension T′.
4. The structural organization of claim 3 , wherein said tub has a depth dimension about one-half the thickness of the leadframe.
5. The structural organization of claim 2 , wherein said electrically conductive clip includes a bridge connected to said columnar part, the bridge part connected to said die.