METHOD OF MANUFACTURING SEMICONDUCTOR DEVICES, CORRESPONDING PRE-MOLDED LEADFRAME AND SEMICONDUCTOR DEVICE
Electrically insulating material is molded onto a sculptured, electrically conductive leadframe structure that includes a pattern of electrically conductive formations such as a die mounting location configured to have at least one semiconductor die arranged thereon, a dummy pad and a tie bar extending between the die mounting location and the dummy pad. A pre-molded leadframe structure results from the electrically insulating material penetrating into spaces between electrically conductive formations in the pattern of electrically conductive formations. At least one portion of the tie bar extending between the die mounting location and the dummy pad is removed to electrically decouple the dummy pad from the die mounting location.
1 . A method, comprising:
molding electrically insulating material onto a sculptured, electrically conductive leadframe structure comprising a pattern of electrically conductive formations to form a pre-molded leadframe structure;
wherein the electrically conductive formations of the pattern comprise a die mounting location configured to have at least one semiconductor die arranged thereon, a dummy pad and a tie bar extending between the die mounting location and the dummy pad;
wherein the electrically insulating material penetrates into spaces between electrically conductive formations in the pattern of electrically conductive formations; and
removing at least one portion of the tie bar extending between the die mounting location and the dummy pad to electrically decouple the dummy pad from the die mounting location.
2 . The method of claim 1 , further comprising removing at least one portion of the tie bar extending between the die mounting location and the dummy pad via laser ablation.
3 . The method of claim 1 , further comprising removing at least one portion of the tie bar extending between the die mounting location and the dummy pad via etching.
4 . The method of claim 1 , wherein:
the pre-molded leadframe structure has a first thickness between opposed first and second opposed surfaces; and
the tie bar has a second thickness less than said first thickness and is left uncovered by the electrically insulating material at the first surface of the pre-molded leadframe structure.
5 . The method of claim 4 , wherein removing at least one portion of the tie bar extending between the die mounting location and the dummy pad results in a recessed portion being formed in the pre-molded leadframe structure.
6 . The method of claim 5 , further comprising:
mounting at least one semiconductor die on the corresponding die mounting location of the pre-molded leadframe structure; and
molding a second electrically insulating material onto the pre-molded leadframe structure having the at least one semiconductor die mounted thereon;
wherein said second electrically insulating material penetrates into the recessed portion formed in the pre-molded leadframe structure.
7 . A pre-molded leadframe, comprising:
a sculptured, electrically conductive leadframe structure comprising a pattern of electrically conductive formations, wherein the electrically conductive formations comprise a die mounting location configured to have at least one semiconductor die arranged thereon, a dummy pad and a tie bar extending between the die mounting location and the dummy pad;
electrically insulating material molded onto the sculptured, electrically conductive leadframe structure;
wherein the electrically insulating material penetrates into spaces between electrically conductive formations in the pattern of electrically conductive formations; and
at least one gap in the tie bar extending between the die mounting location and the dummy pad to electrically decouple the dummy pad from the die mounting location.
8 . The pre-molded leadframe of claim 7 , wherein:
the pre-molded leadframe structure has a first thickness between opposed first and second opposed surfaces; and
the tie bar has a second thickness less than said first thickness and is left uncovered by the electrically insulating material at the first surface of the pre-molded leadframe structure.
9 . The pre-molded leadframe of claim 7 , further comprising a recessed portion in the pre-molded leadframe structure at the location said at least one gap.
10 . A semiconductor device, comprising:
the pre-molded leadframe according to claim 7 , and
at least one semiconductor die mounted at said die mounting location.
11 . The semiconductor device according to claim 10 , further comprising:
a recessed portion in the pre-molded leadframe structure at the location said at least one gap; and
a second electrically insulating material molded onto the pre-molded leadframe structure having the at least one semiconductor die mounted thereon at said die mounting location, wherein said second electrically insulating material penetrates in the recessed portion in the pre-molded leadframe structure.