Laser-induced hot carrier injection (HCI) for accelerated aging of integrated circuits
Laser-assisted integrated circuit (IC) device testing apparatus capable of inducing hot carrier injection (HCI) within selected transistors of an IC device. A laser source of sufficiently high output power (e.g., 1 W) and short pulse duration (e.g., 100 fs) can generate enough hot carriers through a multi-photon (e.g., TPA) carrier injection mechanism to significantly accelerate HCI aging even at low transistor voltage bias (e.g., <1.5V). Rapid laser-assisted HCI transistor aging can selectively degrade transistors of individual functional IC blocks within an IC device.
1 . An integrated circuit (IC) device testing apparatus, comprising:
a stage comprising an area to support an IC device under test (DUT);
an electrical test interface to induce an electric field within one or more transistors of the DUT;
a laser source to output a beam of photons; and
a controller to irradiate the one or more transistors with the beam for a duration sufficient to induce their measurable degradation from charge carriers originated by the beam and accelerated by the electric field.
2 . The IC device testing apparatus of claim 1 , wherein the laser source has an average output power rating of at least 1 W.
3 . The IC device testing apparatus of claim 2 , wherein the beam of photons is delivered with a pulse duration of less than 150 femtoseconds.
4 . The IC device testing apparatus of claim 3 , wherein the pulse duration is no more than 100 femtoseconds.
5 . The IC device testing apparatus of claim 2 , wherein:
the IC DUT is to comprise a semiconductor material having a bandgap; and
the laser source has an output energy less than the bandgap.
6 . The IC device testing apparatus of claim 5 , wherein the laser source has an output wavelength of 1200 nm-1800 nm.
7 . The IC device testing apparatus of claim 6 , wherein the output wavelength is 1550 nm.
8 . The IC device testing apparatus of claim 1 , wherein the electric field is associated with a source-drain bias within the one or more transistors induced by the electrical test interface.
9 . The IC device testing apparatus of claim 8 , wherein the source-drain bias is less than 1.5V.
10 . The IC device testing apparatus of claim 1 , wherein the duration exceeds one minute.
11 . The IC device testing apparatus of claim 1 , wherein a spot of the beam has a diameter of no more than 2 μm, and wherein the beam is to pass through a substrate on a backside of the IC DUT before it irradiates the one or more transistors.
12 . The IC device testing apparatus of claim 1 , wherein the electrical test interface comprises:
a microprobe card comprising a microprobe array;
a host applications board coupled to a power supply to power the IC device, or
a probe card electrically coupled to automated test equipment (ATE).
13 . The IC device testing apparatus of claim 1 , wherein:
the stage comprises a material transparent to the beam of photons and the beam of photons is to pass through the stage; and
the stage is coupled to the controller through an optically-encoded position-feedback loop.
14 . A method of aging one or more transistors of an integrated circuit (IC) device, the method comprising:
inducing an electric field within the transistors of the IC device;
generating a beam of photons with a laser source;
generating charge carriers within the electric field by irradiating the transistors with the beam of photons for a duration sufficient to induce a measurable degradation of the transistors.
15 . The method of claim 14 , further comprising measuring an electrical performance parameter associated with the one or more transistors during, or after, the aging.
16 . The method of claim 14 , wherein the laser source has an average output power rating of at least 1 W within an output wavelength of 1200 nm-1800 nm, and a pulse duration of less than 150 femtoseconds.
17 . The method of claim 14 , wherein inducing the electric field comprises inducing a source-drain bias of no more than 1.2V.
18 . The method of claim 14 , wherein the duration exceeds one minute.
19 . A method of testing an integrated circuit (IC) device, the method comprising:
operating a first instance of a functional IC block under first conditions for a first time period;
performing laser-based hot carrier aging of a second instance of the functional IC block for a second time period, shorter than the first time period;
correlating a laser irradiation time to a normal use time by mapping a performance parameter degradation of the second instance of the functional IC block to that of the first instance of the functional IC block.
20 . The method of claim 19 , wherein:
the IC device comprises a processor including circuitry to execute an instruction set, and wherein the functional IC block comprise at least one of a ring oscillator, a phase locked loop, or a memory array; and
the performance parameter comprises an operational frequency of the functional IC block.