US 12,087,671 B2
Overmolded microelectronic packages containing knurled flanges and methods for the production thereof
Audel Sanchez, Tempe, AZ (US); Jerry Lynn White, Glendale, AZ (US); Hamdan Ismail, Seremban (MY); Frank Danaher, Gilbert, AZ (US); David James Dougherty, Tempe, AZ (US); and Aruna Manoharan, Chandler, AZ (US)
Assigned to NXP USA, Inc., Austin, TX (US)
Filed by NXP USA, INC., Austin, TX (US)
Filed on Mar. 26, 2021, as Appl. No. 17/213,641.
Application 17/213,641 is a division of application No. 16/034,223, filed on Jul. 12, 2018, granted, now 10,998,255.
Prior Publication US 2021/0217685 A1, Jul. 15, 2021
Int. Cl. H01L 23/495 (2006.01); H01L 21/48 (2006.01); H01L 21/56 (2006.01); H01L 23/31 (2006.01)
CPC H01L 23/49503 (2013.01) [H01L 21/4842 (2013.01); H01L 21/4878 (2013.01); H01L 21/56 (2013.01); H01L 23/3121 (2013.01); H01L 23/3142 (2013.01); H01L 23/49568 (2013.01); H01L 23/49575 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method for producing an overmolded microelectronic package, the method comprising:
obtaining a base flange having a flange frontside, a device attachment region, and a knurled surface region, the knurled surface region comprising a first plurality of trenches formed in the base flange, within a border region of the device attachment region, wherein the first plurality of trenches comprises a plurality of U-shaped trenches arranged in a first repeating geometric pattern and a plurality of V-shaped trenches arranged in a second repeating geometric pattern, wherein the first and second repeating geometric patterns are physically imposed over each other, wherein successive instances of the first and second repeating geometric patterns are immediately and continuously adjacent one another, and wherein the plurality of V-shaped trenches intersects the plurality of U-shaped trenches at a trench pattern intersection angle θ1, and wherein 10°<θ1<80°;
performing an overmolding process during which a heated mold compound is directed onto the base flange and flows into the first plurality of trenches, the heated mold compound cooling to form a molded package body bonded to the base flange and covering at least a majority of the knurled surface region; and
before or after the overmolding process, attaching at least one microelectronic device to the flange frontside.