Compression layer on the leadframe to reduce stress defects
AssigneeMicron Technology, Inc.
InventorPatrick W. Tandy
Life of this patent
Estimating the term…
Abstract
An LOC die assembly includes a die dielectrically adhered to the underside of a lead frame. The active surface of the die underlying the attached lead frame is coated with a polymeric material such as polyimide. The underside of the lead frame overlying the die is coated with a layer of soft material, such as silver, which has a lower hardness than the coating on the active surface for absorbing point stresses. Penetration of stacked filler particles into the soft material reduces point stresses on the active die surface and disadhesion stresses on the lead frame components.
Claims31
A semiconductor die assembly, said semiconductor die assembly comprising:
- a semiconductor die having an active surface;
- a lead frame including a plurality of lead members, at least two lead members of the plurality of lead members each having a lead end portion connected to a portion of the lead frame and having a free end portion extending over a portion of said active surface of said semiconductor die;
- and
- a deformable stress relief layer of material attached to a portion of an undersurface of said free end portion of each said at least two lead members of said plurality of lead members.
A semiconductor die assembly, said semiconductor die assembly comprising:
- a semiconductor die having an active surface;
- a dielectric layer covering at least a portion of said active surface of said semiconductor die;
- a lead frame including a plurality of lead members, at least two lead members of the plurality of lead members each having a lead end portion connected to a portion of the lead frame and having a free end portion having, in turn, an undersurface facing, extending over a portion of said active surface of said semiconductor die;
- and
- a deformable stress relief layer of material attached to a portion of said undersurface facing of said free end portion of each lead member of said at least two lead members of said plurality of lead members, said deformable stress relief layer of material comprising a material having a hardness value less than the hardness value of the dielectric layer covering at least a portion of said active surface of the semiconductor die.
Dependencies are inferred from the claim text.