Laser subassembly metallization for heat assisted magnetic recording

Patent metadata

Field	Value
Publication number	US-9227257-B2
Application number	US-201313797839-A
Country	US
Kind code	B2
Filing date	Mar 12, 2013
Priority date	Apr 24, 2012
Publication date	Jan 5, 2016
Grant date	Jan 5, 2016

Abstract

A heat assisted magnetic recording (HAMR) assembly includes a slider, a laser diode and solder connections between the laser diode and the slider. The solder connections mechanically and electrically attach the laser diode to the slider. Each solder connection has a total volume per unit area (i.e., height) of less than or equal to about 15 μm. The solder connections have a first intermetallic zone adjacent to the laser diode, a second intermetallic zone adjacent to the slider, and a eutectic zone of eutectic material between the first and second intermetallic zones. The eutectic zone occupies greater than or equal to about 35% of the total volume per unit area of the solder connection.

First claim

What is claimed is:

1. A laser subassembly comprising:
a laser diode;
a metallization stack on the laser diode, the metallization stack comprising:
an Au metallization wetting layer having a thickness less than about 1000 Å; and
a Pt layer having a thickness from about 300 Å to about 3000 Å, wherein the metallization stack is configured to provide a solder connection having total volume per unit area of less than or equal to about 15 μm and having a first intermetallic zone adjacent to the electronic component, a second intermetallic zone adjacent to the substrate, and a eutectic zone of eutectic material between the first and second intermetallic zones, the eutectic zone occupying greater than or equal to about 35% of the total volume per unit area of the solder connection.

2. The subassembly of claim 1 , wherein the metallization stack further comprises an Ni layer having a thickness from about 300 Å to about 3000 Å.

3. The subassembly of claim 1 , wherein the metallization stack further comprises a Cu layer having a thickness less than about 1000 Å.

4. The subassembly of claim 1 , wherein the metallization stack further comprises an Ti layer between the metallization stack and at least one of an N and P-metal stack of the laser diode.

5. The subassembly of claim 4 , wherein the Ti layer has a thickness from about 100 Å to about 500 Å.

6. A subassembly comprising:
an electronic component;
a metallization stack on the electronic component, the metallization stack comprising:
an Au metallization wetting layer having a thickness less than about 1000 Å; and
a Pt layer having a thickness from about 300 Å to about 3000 Å, wherein the metallization stack is configured to provide a solder connection having total volume per unit area of less than or equal to about 15 μm and having a first intermetallic zone adjacent to the electronic component, a second intermetallic zone adjacent to the substrate, and a eutectic zone of eutectic material between the first and second intermetallic zones, the eutectic zone occupying greater than or equal to about 35% of the total volume per unit area of the solder connection.

7. A method comprising:
aligning contacts of an electronic component with contacts of a substrate, at least one of the electronic component contacts and the substrate contacts comprising a metallization stack comprising: an Au layer having a thickness less than about 1,000 Å; and a Pt layer having a thickness from about 300 Å to about 3000 Å; and
reflow soldering the component contacts and the substrate contacts to form solder connections between the electronic component and the substrate, the solder connections having total volume per unit area of less than 8 μm and having a first intermetallic zone adjacent to the electronic component, a second intermetallic zone adjacent to the substrate, and a eutectic zone of a eutectic material between the first and second intermetallic zones and occupying greater than or equal to about 35% of the total volume per unit area of the solder connection.

8. The method of claim 7 , wherein the metallization stack further comprises a layer of Ti having a thickness of between about 100 Å and 500 Å.

Assignees

• Seagate Technology Llc

Inventors

• Hurley Jon Paul
• Bell Jr Bernard W
• Axdal Steven Harlow Anderson

Classifications

• H10W90/724

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W72/072

  of bump connectors · CPC title

• H10W72/20

  Bump connectors, e.g. solder bumps or copper pillars; Dummy bumps; Thermal bumps · CPC title

• G11B2005/0021

  Thermally assisted recording using an auxiliary energy source for heating the recording layer locally to assist the magnetization reversal · CPC title

• G11B5/105 Primary

  Mounting of head within housing {or assembling of head and housing (G11B5/3103 takes precedence)} · CPC title