1 16-18 April 2002 National Center for Manufacturing Sciences – Commercial Technologies for Maintenance Activities Static Event Health Monitoring A Capability.

116-18 April 2002National Center for Manufacturing Sciences – Commercial Technologies for Maintenance Activities

Static Event Health MonitoringA Capability Improvement Program

Static Event Health MonitoringA Capability Improvement Program

Tom OdomVCD Technologies

San Dimas, California

216-18 April 2002

TopicsTopics History of the Technology Magneto-Optics Prototype ExMOD Detectors Detector Fabrication Proposed Technology Improvements Risk Analysis & Mitigation Conclusions

316-18 April 2002

History of the technologyHistory of the technology Bubble Memories

Developed in the 1970’s as an alternative to magnetic tape data storage

Photo lithographically defined magnetic domains on a single crystal wafer.

Used Large Scale Integration processes developed for the semiconductor industry

Light Modulation Devices Developed for Military applications in the 1980’s. Used Single Crystal Magneto-Optic wafers to modulate light in

nano-second time frames. Missile tracking applications Image Projection

Magneto-Optic Static Event Detectors (MOSED)

416-18 April 2002

History of the technology, (continued)History of the technology, (continued)

Magneto-Optic Static Event Detectors (MOSED) Invented and demonstrated in 1990’s Created to aid in the detection of ESD

events. Magnetic fields created by the ESD

transient changes the properties of the Magneto-Optic thin film deposited on a single crystal substrate

Devices can be remotely reset Effect is observed using a polarizing

microscopeUn-Switched pixel

Switched pixel

516-18 April 2002

Magneto-OpticsMagneto-Optics

Magneto-Optic Effects Kerr Effect for Magneto-Optic Recording Faraday Effect for Light Modulation and memory

devices Also known as the Magneto-Optic Effect, was the

first experimental evidence that light and magnetism are related

Result of ferromagnetic resonance in association with a magnetic field

Resonance causes waves to be decomposed into circularly polarized rays which propagate at different speeds (circular birefringence)

Upon re-combining, owing to the differences in propagation speed, a net phase offset and a resulting rotation of the angle of linear polarization results.

616-18 April 2002

Magneto-Optics, (continued)Magneto-Optics, (continued)

A magnetic field, caused by ESD transient, Changes the way light is polarized in the M-O Material

Polarization changes are permanent until device is externally reset

Effect is observed using a polarizing microscope

UNPOLARIZED LIGHT

VERTICALPOLARIZER HORIZONTAL

POLARIZER

PLANES OF POLARIZATION ROTATED

FIG. 3 – DETAILS OF MAGNETO-OPTIC ESDDEVICE FUNCTION

716-18 April 2002

Prototype ExMOD DetectorsPrototype ExMOD Detectors

Manufactured from Prototype Magneto-Optic wafers

Uses mature Semiconductor wafer processing techniques and materials

3.00

0.020

0.030

Over 6000 die can be produced from a 3 inch diameter wafer

TO-5 packaged Detector

816-18 April 2002

Detector FabricationDetector Fabrication M-O Thin film is grown over non magnetic substrate wafer Wafer is patterned and etched in the sequences shown below M-O devices are characterized and tested to determine electro-optic performance

916-18 April 2002

Prototype DetectorsAdvantages of the old TechnologyPrototype DetectorsAdvantages of the old Technology

Resettable: The device can be reset as many times as desired so long as the current remains below protection level.

Static Memory: The device remains permanently switched after an ESD event until reset. Alternatively, the device can be observed continuously to record the time and threshold of the event.

Small Size: The die can be as small as 500mm x 750mm. External Readout: The device can be read without physical contact, using a polarizing

microscope/optical system. External Reset: The sensing device can be reset with an external non-contact device. Solid State: Operates at extreme temperatures and environments. Fast Switching: Provides discharge detection of fast ESD pulses generated by HBM,

CDM, and MM events. Polarity Sensitivity: If required, the device can distinguish the polarity of the ESD

event. Sensitivity Levels: High or low threshold devices will be available. Pulse Resolution: Current devices can detect ESD events down to 300mA. Custom Configuration: Available for customer specific applications with associated

engineering development.

1016-18 April 2002

Prototype DetectorsDisadvantages of the old TechnologyPrototype DetectorsDisadvantages of the old Technology Difficult to view

Expensive microscopes are required to view the event

Dual Polarizer analyzers

required Difficult for customer to

Assemble High Cost of Fabrication

at low volume Customer acceptance of

new technology

1116-18 April 2002

Proposed Technology Improvements for CTMA / NCMS Cost shareProposed Technology Improvements for CTMA / NCMS Cost share Detector Device

Improvements Replace multi-domain

detector (14 individual sensors) with a single, active, domain

Add a redundant domain for Readout verification

Increase domain size to increase readout signal strength and simplification

Active Domain

Redundant domain

1216-18 April 2002

Proposed Technology Improvements for CTMA / NCMS Cost shareProposed Technology Improvements for CTMA / NCMS Cost share

Alternative Two Cell Structure to discriminate polarity

1316-18 April 2002

Proposed Technology Improvements for CTMA / NCMS Cost shareProposed Technology Improvements for CTMA / NCMS Cost share

Readout Reset Device Improvements Replace the polarizing microscope with an autonomous reader. The new reader will consist of the following components & subsystems Polarized light source Magnifier Charge coupled device (CCD) camera or other sensing device Optical elements that cross polarize incoming and reflected light Processor Result indicatorTo read the MOSED, a Reader is placed above and in proximity to the MOSED to determine its state of polarizationTo reset the device , a permanent or electro-magnet device is integrated with the readout device

Example of Readout Device concept

1416-18 April 2002

Proposed Technology Improvements for CTMA / NCMS Cost shareProposed Technology Improvements for CTMA / NCMS Cost share

Operational Scenario

Step Action 1 The suspect circuit board is placed under the

Reader such that the MOSED device is within the field-of-view

2 The Readers computer triggers a light source and the corner cube at the back side of the MOSED reflects the light back onto the Readers CCD

3 The position of the two magneto-optic pixels are determined

4 The polarizer is rotated to null the signal from the inert pixel

5 The signal from the active pixel is compared to the signal from the inert pixel.

6 Signal differences greater than a specific threshold indicate that the magnetic state of the device has changed and therefore a potentially damaging ESD event has occurred

7 A green (no event) or red (event occurred) light system can be used to indicate the ESD event status

1516-18 April 2002

Risk Analysis & MitigationRisk Analysis & Mitigation

Multiple Deliveries MOSED Device in discrete package Static Sensitive Test devices integrated with the new SED to

characterize performance Multiple threshold devices for wide range of ESD sensitive

devices

Diverse Applications Surge Suppression device will be co-developed

Use state-of-the-art surge suppression technology Couple with MOSED to identify existence of surge

Government Review and Concurrence throughout development cycle Multiple workshops to obtain government input Reduces risk of redesign to meet user needs

1616-18 April 2002

ConclusionsConclusions Detection of ESD events can benefit the life cycle of

electronic devices Manufacturers can improve on processes that historically have

damaged, destroyed or degrade devices. End users can improve their handling of ESD sensitive devices,

resulting in improved reliability in the field. Depot repair facilities can improve their ability to minimize field

returns thereby providing added value to their repair/replacement functions.

The Existing MOSED technology can be improved to overcome deficiencies in a risk-controlled CTMA cost share development program Provides Government and industry users with cost effective tools

necessary to detect, analyze and control ESD events Dual Use technology improvements will result in significant cost

savings for government and industry.