Devices and methods for detecting counterfeit semiconductor devices

Patent metadata

Field	Value
Publication number	US-9941223-B2
Application number	US-201514821160-A
Country	US
Kind code	B2
Filing date	Aug 7, 2015
Priority date	Aug 8, 2014
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

Techniques for providing a tamper mechanism for semiconductor devices are disclosed herein. The techniques include, for example, providing at least one die and at least one strain gauge, orienting the at least one strain gauge to the die, forming an encapsulated semiconductor device by encapsulating the die and each strain gauge within a mold compound to maintain respective orientation, and measuring an initial strain value for the at least one strain gauge after forming the encapsulated semiconductor device.

First claim

What is claimed is:

1. A method for providing a tamper mechanism for semiconductor devices, the method comprising:
providing at least one die and at least one strain gauge;
orienting the at least one strain gauge relative to the at least one die;
forming an encapsulated semiconductor device by encapsulating the at least one die and the at least one strain gauge within a mold compound to maintain respective orientation of the die and each strain gauge;
measuring an initial strain value of the at least one strain gauge after forming the encapsulated semiconductor device; and
adjusting the strain value for each strain gauge to account for shelf-time post manufacturing.

2. The method of claim 1 , further comprising:
storing the at least one initial strain value in a memory of the die.

3. The method of claim 2 , further comprising:
storing a tolerance range for the at least one initial strain value in the memory of the die.

4. The method of claim 3 , further comprising:
measuring a subsequent strain value for the at least one strain gauge; and
comparing the subsequent strain value to the initial strain value; and
determining the encapsulated semiconductor device is compromised when the subsequent strain value is outside the tolerance of the initial strain value.

5. The method of claim 1 , further comprising:
wirelessly communicating, by each strain gauge, the initial strain value for each respective strain gauge to the die to cause the die to store the initial strain value for each respective strain gauge in a memory.

6. The method of claim 1 , further comprising:
electrically communicating, by each strain gauge, the initial strain value for each respective strain gauge to the die to cause the die to store the initial strain value for each respective strain gauge in a memory.

7. The method of claim 1 , further comprising:
providing a memory in communication with the at least one strain gauge;
communicating, by each strain gauge, the initial strain value for each respective strain gauge to the memory to cause the memory to store the initial strain value for each respective strain gauge.

8. The method of claim 1 , wherein the step for orienting the at least one strain gauge on the substrate further comprises:
mounting each strain gauge to at least a portion of the die.

9. The method of claim 1 , further comprising:
integrally forming the at least one strain gauge as part of the die.

10. The method of claim 1 , wherein the at least one strain gauge comprises at least two strain gauges, the method further comprising:
minimizing common mode variation using strain values measured at each of the at least two strain gauges.

11. The method of claim 1 , wherein the strain gauge is a silicon based strain gauge.

12. The method of claim 11 , wherein the strain gauge is a piezoresistive silicon strain gauge.

13. The method of claim 1 , wherein the at least one strain gauge comprises two strain gauges.

14. A semiconductor device that measures strain from tampering, the device comprising:
at least one die;
at least one strain gauge, the die and the strain gauge being encapsulated in a mold compound, the strain gauge for measuring strain induced on the mold compound
communication interfaces operatively coupled to the at least one strain gauge and configured to transmit a strain value for each strain gauge, wherein the strain value has a value that accounts for shelf-time post manufacturing; and
a memory operatively coupled to the communication interfaces and configured to store the strain value for each strain gauge, wherein the communication interfaces and the memory are operatively coupled to the die,
wherein the die is configured to receive the strain value for each strain gauge and cause the memory to store the strain value for each strain gauge, and
wherein the memory is further configured to store a process executable by the die, the process when executed by the die, causes the die to: store at least an initial strain value for each strain gauge; and store one or more tolerance values corresponding to the initial strain value.

Assignees

• Charles Stark Draper Laboratory Inc

Inventors

• Karpman Maurice S

Classifications

• H10W42/405 Primary

  using active circuits · CPC title

• G01L1/06

  by measuring the permanent deformation of gauges, e.g. of compressed bodies · CPC title

• G01L1/18

  using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material · CPC title

• H01L23/576 Primary

  Electricity · mapped topic

• H01L2924/00

  Electricity · mapped topic