US 2026/0305379 A1 · QUAD FLAT NO-LEAD (QFN) MANUFACTURING PROCESS

Abstract

A method of making a lead frame includes a metal structure having opposite first and second sides and prospective device portions having leads with first and second lateral sides extending from a tie bar toward a die attach pad. One or more of the leads includes a first indent in the first lateral side that extends to the first side of the metal structure, and a second indent that extends to the second side of the metal to reduce saw blade loading and mitigate saw burr and lead smear during package singulation. A method of making a packaged electronic device includes a package structure, a semiconductor die enclosed by the package structure, and leads having a first side, a second side, and first and second lateral sides, where the leads include a first indent in the first lateral side that extends to the first side, and a second indent that extends to the second side of the lead.

Claims20

Dependent claims

A method of making a lead frame, comprising:

forming a metal structure having a first side, an opposite second side, and prospective device portions arranged in rows that extend along a first direction and columns that extend along a second direction, the first direction being perpendicular to the second direction, the metal structure including tie bars joining the device portions;
the respective device portions including:
a die attach pad connected to one of the tie bars, and leads spaced apart from the die attach pad, the respective leads have a first lateral side and an opposite second lateral side, the first and second lateral sides extending from one of the tie bars toward the die attach pad parallel to one of the first and second directions, a first one of the leads including a first indent in the first lateral side that extends to the first side of the metal structure, and the first one of the leads including a second indent that extends to the second side of the metal structure.

A method, comprising:

performing a die attach process that attaches semiconductor dies to respective die attach pads of device portions of a lead frame;
performing an electrical connection process that electrically couples a lead portion of respective device portions of the lead frame to a conductive feature of the respective semiconductor dies;
performing a molding process that encloses the semiconductor dies in a package structure;
and
performing a package separation process that separates individual packaged electronic devices from one another, the package separation process including a saw cutting process that cuts through portions of the package structure and lead portions of the respective device portions along a cut direction that causes a cutting saw blade to approach a first lateral side of respective lead portions and to depart an opposite second lateral side of the respective lead portions, the first lateral side of the respective lead portions including a first indent along a bottom side of the respective packaged electronic devices, and the second lateral side of the respective lead portions including a second indent spaced apart from the bottom side of the respective packaged electronic devices.

2 more elements

Dependencies are inferred from the claim text.

Quad flat no-lead (qfn) manufacturing process

Life of this patent

Quad flat no-lead (qfn) manufacturing process

Life of this patent

Abstract

Claims20