# US 8,465,619 B2 · Semiconductor die collet

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,465,619 B2
- Document ID: US8465619B2
- Status: Granted
- Kind: B2
- Application number: 12/844,937
- Filed: 2010-07-28
- Published: 2010-11-18
- Granted: 2013-06-18
- Earliest claimed: 2007-03-24
- Assignees: Texas Instruments Incorporated
- Applicants: Dan Okamoto; Seiichi Yamasaki
- Inventors: Dan Okamoto; Seiichi Yamasaki
- Web page: https://patentgrep.com/patent/US8465619B2

## CPC

- H10P 72/78: using vacuum or suction, e.g. Bernoulli chucks
- H10D 62/117: {Shapes of semiconductor bodies}
- H10W 72/07178: {Means for aligning}
- H10W 72/073: {of die-attach connectors}
- H10W 72/07337: {using a polymer adhesive, e.g. an adhesive based on silicone or epoxy}
- H10W 72/354: {comprising polymers}
- H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
- H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10

## Abstract

Semiconductor device assembly die attach apparatus and methods are disclosed for improvements in attaching a semiconductor die to a die pad. Preferred methods of the invention include steps for positioning a semiconductor die on a bearing surface of a collet and retaining the die on the bearing surface of the collet using a vacuum force. A pushing force is also exerted on the die adjacent to the applied vacuum force. The pushing force opposes flexion of the die in the direction of the vacuum force. In further steps, the die is placed on a die pad, and die attach adhesive is interposed between the die and the die pad. A preferred method includes applying a pushing force to bow the central region of the die toward the die pad. In a preferred apparatus of the invention, a collet has a body including a bearing surface for receiving a die and a vacuum for holding it. A chamber encompassed by the bearing surface is adapted for applying the force of expelled gas against a die borne on the bearing surface. The collet is configured for holding a die surface against the bearing surface and for simultaneously pushing outward on the center region of the die so held.

## Claims

### Claim 1

A collet comprising:
a body having a bearing surface for receiving a semiconductor die and a chamber having an open side bounded by the bearing surface;
a vacuum groove in the bearing surface configured for pulling a die surface against the bearing surface;
a vacuum port for communicating a vacuum force to the vacuum groove; and
an expelling port for communicating an expelled gas to the chamber;
whereby the vacuum force is adapted for holding the die surface against the bearing surface and the expelled gas is adapted for asserting a force at the center region of a held die in a direction opposite the vacuum force to limit die flexion.

### Claim 2 (depends on 1)

A collet according to claim 1 wherein the expelled gas is adapted for pushing the center region of a held die outward beyond the plane of the bearing surface.

### Claim 3 (depends on 1)

A collet according to claim 1 further comprising a flexible skin attached to the body and covering the chamber.