Back to results
US 9,070,697 B2Granted
Device for detecting a laser attack in an integrated circuit chip
AssigneeSTMicroelectronics (Rousset) SAS
InventorsFabrice Marinet, Jimmy Fort, Alexandre Sarafianos, Julien Mercier
Life of this patent
Estimating the term…
Abstract
A device for detecting a laser attack made on an integrated circuit chip comprises a bipolar transistor of a first type formed in a semiconductor substrate, that bipolar transistor comprising a parasitic bipolar transistor of a second type. A buried region, forming the base of the parasitic bipolar transistor, operates as a detector of the variations in current flowing caused by impingement of laser light on the substrate.
Claims7
A circuit, comprising:
- a substrate of a first conductivity type;
- a buried region of a second conductivity type;
- an encircling region of the second conductivity type extending from a top surface of the substrate to contact the buried region;
- a well region of the first conductivity type surrounded by said encircling region and said buried region;
- a surface region of the second conductivity type formed in said well region;
- wherein the surface region, well region and buried region form a vertical bipolar transistor of a first type;
- wherein the vertical bipolar transistor includes a parasitic bipolar transistor of a second type;
- wherein a base terminal of said parasitic bipolar transistor is provided by said buried region;
- and
- wherein said buried region detects laser beam impingement on said substrate.
7 more elements
Dependencies are inferred from the claim text.