Lead frame having chip mounting part and leads of different thicknesses

• US 6,936,915 B2
• Filed: 11/01/2001
• Issued: 08/30/2005
• Est. Priority Date: 11/01/2000
• Status: Expired due to Fees

• Current Assignee: Mitsui High-Tec Incorporated
• Original Assignee: Mitsui High-Tec Incorporated
• Inventors: Fujita, Katsufusa
• Primary Examiner(s): MAI, ANH D
• Application Number:
  US10/399,819
• Publication Number:
  US 20040150077A1
• Time in Patent Office: 1,398 Days
• Field of Search: 257/666, 257675-676, 257/690, 257/693, 257/696, 257/670
• US Class Current: 257/693
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/85399 Material
• CPC Class Codes: H01L 23/49537 Plurality of lead frames mounted in one device
• CPC Class Codes: H01L 23/49548 Cross section geometry H01L23/49562 takes precedence
• CPC Class Codes: H01L 23/49551 characterised by bent parts
• CPC Class Codes: H01L 23/49562 for devices being provided for in H01L29/00
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01046 Palladium [Pd]
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/207 Diameter ranges

Abstract

A lead frame according to this invention comprises: a semiconductor chip mounting part having an engagement hole formed on its one side; and a lead part including a supporting lead fit in said engagement hole of the semiconductor chip mounting part so as to support said semiconductor chip mounting part, said supporting lead being made of a thinner-walled material than that of the semiconductor chip mounting part and an outer lead arranged in parallel to said supporting lead. The supporting lead involves a fitting portion having a wider width than a lead width of the supporting lead and fit in said engagement hole of said semiconductor chip mounting part.

Claims

1. A lead frame comprising:

a semiconductor chip mounting part made of a thick-walled material;

a supporting lead made of a thin-walled material which supports said semiconductor chip mounting part and also serves as an outer lead; and

an outer lead arranged in parallel to the supporting lead,

wherein a through-hole is made in one side along the one side of the semiconductor chip mounting part so as to have a width equal to or longer than that of a semiconductor chip to be mounted;

an opening is formed from a center position of the through-hole toward ends of the one side so as to be wider than a width of the supporting lead; and

in the through-hole and the opening between the side ends, a fitting portion having a wider width than the supporting lead, which is formed at the tip of the supporting lead, is fit to sink relative to the surface of the semiconductor chip mounting part so that the semiconductor chip mounting part and the supporting lead is coupled and the through-hole forms a groove from the plane on which the semiconductor chip is mounted.

2. The lead frame as claimed in claim 1, wherein the tip of the supporting lead which has a wider width than that of the supporting lead where it is coupled with said semiconductor chip mounting part is bent at a location where the tip of the supporting lead has a wider width than that of the supporting lead so that a surface of the semiconductor chip mounting part is located at a lower level than an extending line of said supporting lead, or the one end thereof is located at a lower surface of the supporting lead.

3. The lead frame according to claim 1 further comprising a semiconductor chip mounted on the semiconductor chip mounting part.

4. A lead frame comprising:

a semiconductor chip mounting part made of a thick-walled material having a surface to which a semiconductor chip can be mounted;

a supporting lead made of a thin-walled material which supports said semiconductor chip mounting part and also serves as an outer lead; and

an outer lead arranged in parallel to the supporting lead;

wherein an engagement hole having a wider width than that of the supporting lead is made into one side along the one side of the semiconductor chip mounting part, and is opened from a central portion toward the side ends to be wider than the width of the supporting lead;

a fitting portion, which is formed at a tip of the supporting lead, is caulked on the engagement hole and at the side ends thereof so that the supporting lead is coupled with the semiconductor chip mounting part, and a tip portion of the supporting lead with a wider width than that of the supporting lead, is led out from the area where it is coupled with the semiconductor chip mounting part, the tip portion bent at a location where the tip portion has a wider width than that of the supporting lead so that a surface of the semiconductor chip mounting part is located at a lower level than an extending line of said supporting lead, or one end thereof is located at a lower surface of the supporting lead.