1. A method for analyzing an integrated circuit (C), including:
a step (102) for applying laser radiation at a point on the surface of the circuit (C);
a step (106) for exciting the circuit (C) thus subjected to laser radiation by applying an electrical excitation signal;
a step (106) for collecting the response of the circuit to the excitation, the circuit being subjected to laser radiation;
at least one step (106) for measuring the phase difference between the response to the excitation of the circuit subjected to laser radiation and a reference response of the circuit in the absence of laser radiation applied to the circuit.
2. A method according to claim 1, characterized in that the reference response is the excitation signal of the circuit shifted temporarily with respect to the response of the circuit subjected to laser radiation by a delay equal to the propagation time of the excitation signal through the circuit in the absence of laser radiation.
3. A method according to claim 1, characterized in that the reference response is a signal which is a function of the response expected at the output of the circuit in the absence of laser radiation.
4. A method according to claim 3, characterized in that the reference response is equal to the response expected at the output of the circuit operating normally in the absence of radiation.
5. A method according to claim 3, characterized in that the reference response is a transform of the response expected at the output of the circuit in the absence of radiation, of the same frequency, and for which the amplitude andor the pulse width andor the shape of pulses have been modified.
6. A method according to claim 1, characterized in that the or each step for measuring the phase shift between the response to the excitation of the circuit subjected to laser radiation and a reference response of the circuit in the absence of laser radiation applied to the circuit comprises:
multiplying the response to the excitation of the circuit subjected to laser radiation by the reference response of the circuit in the absence of laser radiation applied to the circuit; and
filtering the product obtained through a low-pass filter.
7. A method according to claim 1, characterized in that the step (106) for measuring the phase difference between the response to the excitation of the circuit subjected to laser radiation and the reference response of the circuit in the absence of laser radiation applied to the circuit is carried out by processing both responses which, in the absence of laser radiation, have a zero initial relative phase shift, in order to obtain, as phase difference, the variation in the duty cycle.
8. A method according to claim 1, characterized in that the step (106) for measuring the phase difference between the response to the excitation of the circuit subjected to laser radiation and the reference response of the circuit in the absence of laser radiation applied to the circuit is carried out by processing both responses, both of which are considered in the absence of laser radiation with a relative phase shift equal to 90\xb0, in order to obtain, as phase difference, the phase delay.
9. A method according to claim 1, characterized in that it comprises in addition to the step (106) for measuring the phase difference between the response to the excitation of the circuit subjected to laser radiation and a reference response of the circuit in the absence of laser radiation applied to the circuit:
an additional step for measuring the additional phase difference between the response to the excitation of the circuit subjected to laser radiation and the reference response of the circuit in the absence of laser radiation applied to the circuit and shifted by a predetermined additional phase difference; and
a step for calculating the phase delay and the variation in duty cycle between the response to the excitation of the circuit subjected to laser radiation and the reference response of the circuit in the absence of laser radiation applied to the circuit from said measured phase difference and said measured additional phase difference.
10. A method according to claim 9, characterized in that said predetermined additional phase difference is equal to 90\xb0.
11. A method for observing an integrated circuit (C), characterized in that it includes:
for a plurality of points (X, Y) on the surface of the integrated circuit, a step (102, 106) for analyzing the circuit according to claim 1 for the determination of the phase difference between the response to the excitation of the circuit subjected to laser radiation at a point (X, Y) on the surface of the integrated circuit (C) and a reference response of the circuit in the absence of laser radiation applied to the circuit; and
a step (108) for creating an image of the integrated circuit (C) illustrating a value representing the phase difference between the response to the excitation of the circuit subjected to laser radiation and the reference response of the circuit in the absence of laser radiation applied to the circuit for each point of application (X, Y) of the laser radiation.
12. A method according to claim 1, characterized in that the laser radiation has a wavelength of between 800 nm and 1400 nm.
13. A method according to claim 12, characterized in that the laser radiation wavelength is chosen to be in the group consisting of 1064 nm and 1340 nm.
14. A method according to claim 1, characterized in that the laser radiation is applied at each point (X, Y) synchronously with the circuit excitation step (106).
15. A method according to claim 1, characterized in that the laser radiation is applied at each point (X, Y) asynchronously with the circuit excitation step (106).
16. A method according to claim 1, characterized in that the laser radiation is pulsed with at least one pulse at each point (X, Y) on the circuit.
17. An analysis installation including:
means (30) for applying laser radiation at a point on the surface of the circuit (C);
means (16, 18; 50) for exciting the circuit (C) thus subjected to laser radiation by applying an electrical excitation signal;
means (22) for collecting the response of the circuit to the excitation, the circuit being subjected to laser radiation;
means (16, 24; 50) for providing a reference response of the circuit in the absence of laser radiation applied to the circuit; and
means (26, 28) for measuring the phase difference between the response to the excitation of the circuit subjected to laser radiation and the reference response of the circuit in the absence of laser radiation applied to the circuit.
18. An analysis installation according to claim 17, characterized in that the means (26, 28) for measuring the phase difference between the response to the excitation of the circuit subjected to laser radiation and the reference response of the circuit in the absence of laser radiation applied to the circuit comprise means for carrying out the processing of both responses which, in the absence of laser radiation, have a zero initial relative phase shift, in order to obtain, as phase difference, the variation in the duty cycle.
19. An analysis installation according to claim 17, characterized in that the means (26, 28) for measuring the phase difference between the response to the excitation of the circuit subjected to laser radiation and the reference response of the circuit in the absence of laser radiation applied to the circuit comprise means for carrying out the processing of both responses which, in the absence of laser radiation, have a relative phase shift equal to 90\xb0, in order to obtain, as phase difference, the phase delay.
20. An analysis installation according to claim 17, characterized in that it includes, in addition to the means (26, 28) for measuring the phase difference between the response to the excitation of the circuit subjected to laser radiation and a reference response of the circuit in the absence of laser radiation applied to the circuit:
additional means (126, 128, 130) for measuring the additional phase difference between the response to the excitation of the circuit subjected to laser radiation and the reference response of the circuit in the absence of laser radiation applied to the circuit shifted by a predetermined additional phase difference; and
means (150) for calculating the phase delay and the variation in duty cycle between the response to the excitation of the circuit subjected to laser radiation and the reference response of the circuit in the absence of laser radiation applied to the circuit from said measured phase difference and said measured additional phase difference.
21. An installation according to claim 20, characterized in that said predetermined additional phase difference is equal to 90\xb0.
22. An observation installation characterized in that it includes:
for a plurality of points (X, Y) on the surface of the integrated circuit, an installation for analyzing the circuit according to claim 17 for the determination of the phase difference between the response to the excitation of the circuit subjected to laser radiation at a point (X, Y) on the surface of the integrated circuit (C) and a reference response of the circuit in the absence of laser radiation applied to the circuit; and
means (29) for creating an image of the integrated circuit (C) illustrating a value representing the phase difference between the response to the excitation of the circuit subjected to laser radiation and the reference response of the circuit in the absence of laser radiation applied to the circuit for each point of application (X, Y) of the laser radiation.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A differential assembly comprising:
a yoke, attached to a drive shaft, for driving a pinion head;
inner and outer pinion bearing assemblies;
a separable mounting plate, the mounting plate being secured to the inner pinion bearing assembly;
a cavity defined by a housing for receiving a pinion assembly;
wherein the outer pinion bearing assembly is integrally mounted within the housing, wherein the inner pinion bearing assembly includes an adjusting mechanism; and wherein the pinion assembly is straddle mounted between the inner and outer pinion bearing assemblies.
2. A differential assembly according to claim 1, wherein the mounting plate of the inner pinion bearing assembly is secured to the housing by at least one bolt.
3. A differential assembly according to claim 1, wherein the inner and outer pinion bearing assemblies each further comprise an inner race, an outer race and a bearing disposed between the inner and outer races.
4. A differential assembly according to claim 1, wherein the adjusting mechanism includes a threaded cup.
5. A differential assembly according to claim 1, wherein the adjusting mechanism includes at least one shim pack, and wherein the mounting plate may be shimmed by said at least one shim pack being disposed under the mounting plate.
6. A differential assembly according to claim 1, wherein a mounting distance for the pinion head may be established by machining the housing.
7. A differential assembly comprising:
inner and outer pinion bearing assemblies;
a separable mounting plate, the separable mounting plate being secured to the inner pinion bearing assembly;
a cavity defined by a housing for receiving a pinion assembly;
wherein the outer pinion bearing assembly is integrally mounted within the housing; wherein the inner pinion bearing assembly further includes a threaded cup; and wherein the pinion assembly is straddle mounted between the inner and outer pinion bearing assemblies.
8. A differential assembly according to claim 7, wherein the threaded cup may be threaded to a desired position to preload the inner and outer pinion bearing assemblies.
9. A differential assembly according to claim 7, wherein the inner pinion bearing assembly further comprises a lock ring and a stake, wherein the lock ring is secured to the stake to prevent rotation of the threaded cup.
10. A differential assembly according to claim 7, wherein the mounting plate of the inner pinion bearing assembly is secured to the housing by at least one bolt.
11. A differential assembly according to claim 7, wherein the inner and outer pinion bearing assemblies each further comprise an inner race, an outer race and a bearing disposed between the inner and outer races.
12. A differential assembly according to claim 7, wherein the mounting plate may be shimmed by at least one shim pack disposed under the mounting plate.
13. A differential assembly according to claim 7, wherein a mounting distance for the pinion head may be established by machining the housing.
14. A differential assembly comprising:
a carrier housing having a first opening and a second opening;
an outer pinion bearing assembly integrally mounted within said carrier housing at said first opening;
an inner pinion bearing assembly positioned at said second opening;
a pinion assembly mounted between said outer pinion bearing and said inner pinion bearing;
wherein said inner pinion bearing is fixed to a removable support plate at said second opening of said carrier housing; and wherein said pinion assembly is installed through said second opening.
15. A differential assembly as recited in claim 14, wherein the removable mounting plate of the inner pinion bearing assembly is fixed to said housing by at least one bolt.
16. A differential assembly as recited in claim 14, wherein the inner and outer pinion bearing assemblies each further include an inner race, an outer race and a bearing disposed between the inner and outer races.
17. A differential assembly as recited in claim 14, wherein the removable support plate may be shimmed by at least one shim pack disposed under the removable support plate.
18. A differential assembly as recited in claim 14, wherein a mounting distance for the pinion head may be established by machining the carrier at the first opening.