Self-limiting electrical triggering for initiating fracture of frangible glass

US10026579B2 · kind B2 · utility

Assignee

• Palo Alto Research Center Incorporated · US

Inventors

• Gregory Whiting · Menlo Park, US
• Scott Limb · Palo Alto, US
• Christopher L. Chua · San Jose, US
• Sean Garner · San Francisco, US
• Sylvia Joan Smullin · Menlo Park, US
• Qian Wang · San Jose, US
• Rene A. Lujan · Sunnyvale, US

Key dates

• Filing date: Jul 26, 2016
• Grant date: Jul 17, 2018
• Expiry date: Sep 20, 2036

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/78
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A transient electronic device includes electronic elements (e.g., an SOI- or chip-based IC) and a trigger mechanism disposed on a frangible glass substrate. The trigger mechanism includes a switch that initiates a large trigger current through a self-limiting resistive element in response to a received trigger signal. The self-limiting resistive element includes a resistor portion that generates heat in response to the trigger current, thereby rapidly increasing the temperature of a localized (small) region of the frangible glass substrate, and a current limiting portion (e.g., a fuse) that self-limits (terminates) the trigger current after a predetermined amount of time, causing the localized region to rapidly cool down. The frangible glass substrate is engineered such that a stress profile produced by the rapid heating/cooling of the localized region generates an initial fracture force that subsequently propagates throughout the glass substrate, whereby sufficient potential energy is released to powderize the electronic elements.