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October 2011 EUFANET workshop Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, t he Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
Automotive
mixed-mode device used for Engine control
One
feature of this device is to control an external ballast transistor and regulate VIN:
Simplified application schematic:
VIN11.5V, control pin output current = 10uA.
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
-10µA/+10µA
push-pull current circuit was found defective
Capability was significantly reduced and inferior to -1µA:
Pull-up current capability measurement:
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
The failure was temperature dependant => Soft Defect Localization analysis
After FA & design study a MosFet was
pinpointed The cascode MOS appeared to be pinched-off and did not let pass the 10uA current
This result lets suspect a voltage overstress degradation mechanism that resulted in trapped charges at the Si/SiO2 interface and in the gate oxide.
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
The damaged MOSFET was used to cascode a current source and protect it from the charge pump voltage If the lower MOSFET was switched OFF, the cascode source would be floating and its voltage could rise up to the charge pump voltage, thus exceeding the maximum Vgs rating and degrading the MOSFET
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
SCM technique uses a conductive probe tip to form a metal-oxide-semiconductor capacitor with the sample. By detecting dC/dV changes, it provides a picture of the carrier concentration and can also highlight potential trapped charges After cross-sectional sample preparation, the analysis evidenced an anomalous “Ptype carriers profile” under the gate, at the edge of the FOX bird’s beak This signature could not be the result of a bad implant, as the shape was not consistent with an isotropic diffusion. It was then the direct consequence of charges locally trapped under the gate
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
By simulation, the critical parameters of the simulations and their effect matched to the key parameters in the SCM Indeed, the Junction shift as function of the bias applied to the Tip and to the Bulk was verified with the Physical modeling
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Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, the Energy Efficient Solutions logo, mobileGT, PowerQUICC, QorIQ, StarCore and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, ColdFire+, CoreNet, Flexis, Kinetis, MXC, Platform in a Package, Processor Expert, QorIQ Qonverge, Qorivva, QUICC Engine, SMARTMOS, TurboLink, VortiQa and Xtrinsic are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2011 Freescale Semiconductor, Inc.
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