Reliable physical unclonable function for device authentication
The present disclosure relates to a secure device having a physical unclonable function and methods of manufacturing such a secure device. The device includes a substrate and at least one high-k/metal gate device formed on the substrate. The at least one high-k/metal gate device represents the physical unclonable function. In some cases, the at least one high-k/metal gate device may be subjected a variability enhancement. In some cases, the secure device may include a measurement circuit for measuring a property of the at least one high-k/metal gate device.
1. A method of manufacturing a secure device having a physical unclonable function, the method comprising:
providing a substrate for the secure device; and
forming at least one high-k/metal gate device on the substrate, the at least one high-k/metal gate device representing the physical unclonable function; and
varying an ambient condition to which the at least one high-k/metal gate device is exposed during the forming, to create a variation in a physical property of the at least one high-k/metal gate device that is measurably unique relative to variations in physical properties of other high-k/metal gate devices manufactured in a onion batch with the at least one high-k/metal gate device and wherein the physical property is known to be sensitive to variations in the ambient condition.
2. The method of claim 1 , wherein the at least one high-k/metal gate device comprises a high-k dielectric.
3. The method of claim 2 , wherein the high-k dielectric comprises at least one of:
a lanthanum oxide;
an alkaline earth oxide; or
an earth metal oxide.
4. The method of claim 1 , wherein the ambient condition comprises at least one of:
a varying level of an available dopant;
a varying temperature; or
a varying level of oxygen.
5. The method of claim 1 , further comprising:
performing at least one patterning process on the at least one high-k/metal gate device to alter the variation, wherein the at least one patterning process comprises at least one of:
a laser anneal;
a lithography process;
a reactive ion etching process; or
a chemical mechanical planarization process.
6. The method of claim 1 , further comprising:
including a measurement circuit in the secure device, wherein the measurement circuit is configured to measure the physical property of the at least one high-k/metal gate device for authenticating the secure device.
7. The method of claim 6 , wherein the physical property comprises at least one of:
a resistance;
a capacitance;
an impedance;
an inductance;
a transmittance; or
a voltage response.
8. The method of claim 7 , wherein a signature having one or more physical unclonable function values is derived from the physical property.
9. The method of claim 8 , wherein the measurement circuit is further configured to:
derive a binary key from the signature, wherein the binary key is derived from the signature via the measurement circuit by applying a threshold to the one or more physical unclonable function values.
10. The method of claim 6 , wherein the measurement circuit is formed on the substrate.
11. The method of claim 1 , wherein the secure device comprises an integrated circuit.
12. A method of manufacturing a secure device having a physical unclonable function, the method comprising:
providing an integrated circuit comprising at least one high-k/metal gate device, the at least one high-k/metal gate device representing the physical unclonable function;
varying an ambient condition to which the at least one high-k/metal gate device is exposed during the forming, to create a variation in a physical property of the at least one high-k/metal gate device that is measurably unique relative to variations in physical properties of other high-k/metal gate devices manufactured in a common batch with the at least one high-k/metal gate device, and wherein the physical property is known to be sensitive to variations in the ambient condition; and
including a measurement circuit in the integrated circuit that is configured to measure the physical property of the at least one high-k/metal gate device for authenticating the secure device, wherein the at least one property is affected by the unique variation.
13. The method of claim 12 , wherein the at least one high-k/metal gate device comprises a high-k dielectric.
14. The method of claim 12 , wherein the ambient condition comprises at least one of:
a varying level of an available dopant;
a varying temperature; or
a varying level of oxygen.
15. The method of claim 12 , further comprising:
performing at least one patterning process on the at least one high-k/metal gate device to alter the variation, wherein the at least one patterning process comprises at least one of:
a laser anneal;
a lithography process;
a reactive ion etching process; or
a chemical mechanical planarization process.
16. The method of claim 12 , wherein the physical property comprises at least one of:
a resistance;
a capacitance;
an impedance;
an inductance;
a transmittance; or
a voltage response.
17. A secure device having a physical unclonable function, the secure device comprising:
a substrate;
at least one high-k/metal gate device formed on the substrate, the at least one high-k/metal gate device representing the physical unclonable function and formed using a variability enhancement that varies an ambient condition to which the at least one high-k/metal gate device is exposed during manufacture, wherein a physical property of the at least one high-k/metal gate device is known to be sensitive to variations in the ambient condition; and
a measurement circuit configured to measure at least one property of the at least one high-k/metal gate device for authenticating the secure device.
18. The secure device of claim 17 , wherein the at least one high-k/metal gate device comprises a high-k dielectric.
19. The secure device of claim 17 , wherein the ambient condition comprises at least one of:
a varying level of an available dopant;
a varying temperature; or
a varying level of oxygen.
20. A secure device having a physical unclonable function, the secure device comprising:
a substrate; and
at least one high-k/metal gate device formed on the substrate, the at least one high-k/metal gate device representing the physical unclonable function and formed using a variability enhancement that varies an ambient condition to which the at least one high-k/metal gate device is exposed during manufacture, wherein a physical property of the at least one high-k/metal gate device is known to be sensitive to variations in the ambient condition.
21. The secure device of claim 20 , wherein the at least one high-k/metal gate device comprises a high-k dielectric.
22. The secure device of claim 20 , wherein the ambient condition comprises at least one of:
a varying level of an available dopant;
a varying temperature; or
a varying level of oxygen.
23. The secure device of claim 20 , further comprising:
a measurement circuit located on the substrate, wherein the measurement circuit is configured to measure the physical property of the at least one high-k/metal gate device for authenticating the secure device.