GLAST LAT ProjectTKR Peer Design Review, Mar 24-25, 2003 5BNick Virmani 1 GLAST Large Area Telescope Tracker Subsystem Gamma-ray Large Area Space Telescope

GLAST LAT Project TKR Peer Design Review, Mar 24-25, 2003

5B Nick Virmani 1

GLAST Large Area TelescopeGLAST Large Area TelescopeTracker Subsystem

Gamma-ray Large Gamma-ray Large Area Space Area Space TelescopeTelescope

5B: EEE Parts and Electronic Packaging

Nick VirmaniLAT EEE parts and Electronic Packaging Manager

[email protected](202) - 767 - 3455


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OutlineOutline

• EEE Parts Requirements• EEE Part Implementation Plan• EEE Parts Status • Process Flow for ASICs and MCM Fabrication, Screening,

and Qualification• Radiation Testing• Radiation testing Results• Electronic Packaging Program• ASIC and MCM Documentation Status• EEE Parts Issues & Risk Mitigation• Manufacturing and Test Process Flow of TKR Hardware


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EEE Parts RequirementsEEE Parts Requirements

• Requirements Summary– Parts screening and qualification per GSFC 311-INST-001,

Level 2,– Additional requirements outlined in the LAT EEE parts

program control plan, LAT-MD-00099-1 – Review and approve EEE Part Lists.– Derate EEE Parts per PPL-21

• Review and approve derating information before drawing sign-offs.

– Perform stress analysis– Parts Control Board (PCB) Approach, a partnership

arrangement with NASA/GSFC parts engineer and code 562.


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EEE Parts Implementation PlanEEE Parts Implementation Plan

• Part lists are reviewed and approved by the project PCB prior to flight procurements.

• Special considerations include:– Radiation evaluation of all active components– Radiation testing (TID and/or SEE ) when necessary– Parts stress analysis– PIND testing on all cavity devices– Destructive Physical Analysis (DPA), when applicable– Mandatory in process inspections and verification on

Multi-Chip Modules (MCMs) and other devices as required– Life Testing if Quality Conformance Inspection (QCI) data

within one year of the lot being procured is not available– No pure tin, cadmium, and zinc plating is allowed – Vendor surveillance where required.


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EEE Parts Implementation PlanEEE Parts Implementation Plan

• Special considerations include cont’d:– 50V ceramic capacitors require 850C/85RH low voltage

testing– Mandatory surge current testing on all tantalum

capacitors– MCM testing and verification requires special evaluation

as outlined in the EEE parts plan– Age control requirements. Lot Date Code (LDC) older than

5 years requires DPA and room temperature re-screen– Parts traceability from procurement to assembly of board

and components.– GIDEP Alerts & NASA Advisories review and disposition

from selection of parts until subsystem integration.– Parts Identification list (PIL) includes LDC, MFR,

Radiation information on the flight lot


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EEE Parts StatusEEE Parts Status

• The TKR subsystem EEE parts lists have been reviewed by the PCB all parts have been approved except ASIC screening, MCM screening, flex cable screening and qualification, and cristek connectors.

• Resettable polyswitch fuse specification LAT-SS-01116-04 was approved by the PCB and will review test data after completion of the tests.

• All part test data will be reviewed prior to flight assembly by the PCB where applicable.

• The goal is to approve the remaining parts on the parts lists prior to the CDR

• Discuss EEE parts availability weekly, to support fabrication schedule.

• Perform 100% incoming inspection as per defined procedures.


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EEE Parts StatusEEE Parts Status

• Performed stress analysis of most of the approved parts on the parts lists and they meet derating criteria after stress application. Will complete the remaining analysis by the CDR.

• Perform screening and qualification tests as required per approved procedure.

• Hold regular meeting with GSFC Parts Engineer to resolve any parts-related issues and approve parts though the Parts Control Board (PCB).

• Attribute data for screening and lot specific qualification/QCI data shall be reviewed for acceptance of parts for flight.

• Parts Identification List (PIL) and As-built parts lists is maintained and will be submitted to GSFC.


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Process Flow for ASICs and MCM Process Flow for ASICs and MCM Fabrication, Screening, and QualificationFabrication, Screening, and Qualification

WAFERS RECEIVE FROM MOSIS USING

AGILENT PROCESS

INSPECTIONWAFER

LAPPINGMOUNT

PROCEDURE

WAFER SAW

PROCEDURE

OPTICAL QC GATE

2ND OPTICAL INSPECTION

PACK DIE IN WAFFLE PACK OR GEL PACK FOR SHIPPING TO TELEDYNE WITH DATA

PACKAGE & TRACEABILITY

CONTROL MONITORS

FOR RADIATION

SAMPLE RADIATION TESTING

100% INSPECTION

Wafer Probe 100% Sort

dies

Wafer Probe Procedure

Receive/Inspect ASIC die in waffle or gel packs,

PWBs and parts, record data at Teledyne

VERIFY ADHESION AND

INSPECTION

Clean/Bake PWBs as per NASA-STD-

8739.3

BOND PITCH ADAPTER FLEX

CIRCUIT

DPA & Scanning Electron

Microscope (SEM)

Inspection


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Clean Die Bonding Surfaces of PWB Plasma and Local

cleaning (IPA)

Apply Die Attach Material to PWB

(MCM)

Die Attach Material Cure per

Manufacturer’s Suggestions

Plasma Clean PWB and Die Bonding

Surfaces for Wedge Wire Bonding

Wirebond of ASIC die and MCM PWB

Die Attach Monitor

In Process Wirebond Pull Testing on

samples and Monitor

COB Die Placement on the PWB

Install connectors by hand-soldering

Functional Testing and verification of MCM as per test

program *

Rework or replace dies if required

100% Optical Inspection

* Test all register and memory locations, all I/O functions, including LVDS bias levels, all inter-* Test all register and memory locations, all I/O functions, including LVDS bias levels, all inter-chip communication, power consumption, all amplifiers by charge injection and test the trigger chip communication, power consumption, all amplifiers by charge injection and test the trigger output, and for excessive noise or instabilities.output, and for excessive noise or instabilities.

Rework, if required

Encapsulate ASIC die and bond areas



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100% Inspection

Full Functional Testing using

configured software test & EGSE

Full Functional Testing using

configured software test & EGSE

Pack each MCM individually in the

ESD container with pigtail hanging outside of the

container for testing

MCM ready functional test &

environmental test

Conformal Coat

100% thermal cycling –30 to +85

degrees C, unpowered

Clean

Functional Testing

100% Visual

Inspection

100% Dynamic burn-in at 85

degrees C with continuous

monitoring for 168 hours

100% Inspect

Review results data package



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100% VisualInspection

Present data to the Parts Control Board (PCB) Screening &

Qualification

MCM ready for next step and sample

selection for qualification

Select 38 MCMs from screened lot

Radiograph 2 samples and DPA

on 1 sample

Store MCM in nitrogen purge

storage

100% powered thermal cycling –30 to +85 degrees C,

100 cycles

Obtain approval from PCB

100% Visualinspection

100% Dynamic burn-in testing for

240 hours

100% Visual

Inspection

Thermal Vac testing for 10 samples, 12

cycles



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Vibration Testing 10 samples

100% Visual

Inspection

Review of DataPCB Approval

Radiograph CSAM & DPAFunctional

Testing



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Radiation TestingRadiation Testing

• All EEE parts are being reviewed by PCB and screened for radiation susceptibility against the radiation specification defined in GLAST IRD-433-SPEC-001.

• Requirements:– Total dose requirement, including standard factor of 2

safety margin is 4.5 Krad (Si) for 5 years behind 100 mils Aluminum.

– Our goal is to test all parts up to 10 Krads (Si).– SEE Damage – no SEE shall cause permanent damage to

the subsystem.


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Radiation TestingRadiation Testing

• SEE Rate and Effects Analysis:– SEE rates and effects shall take place based on threshold

LET (LETth) as follows:

SEE immune is defined as a device have an LETth > 37 MeV*cm2/mg

– Our goal is to test each part to this specification.

Device Threshold Environment to be Assessed

LETth < 15 MeV*cm2/mg Cosmic Ray, Trapped Protons, Solar Heavy Ion and Proton

LETth =15-37 MeV*cm2/mg

LETth > 37 MeV*cm2/mg

Cosmic Ray, Solar Heavy Ion

No analysis required


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Radiation Testing ResultsRadiation Testing Results

• Radiation testing was performed on engineering parts produced using similar processes and materials.

• An earlier version of ASICs tested and met requirements.• No outstanding issues


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Electronic Packaging ProgramElectronic Packaging Program

• Electronic Packaging, Manufacturing, Test, and Process Control program– Manufacturing, Assembly, and Quality Control of electronic

system will be in compliance to the NASA technical standards: NASA-STD-8739.1, NASA-STD-8739.2, NASA-STD-8739.3, NASA-STD-8739.4, NASA-STD-8739.7, and IPC-6012 & 6013.

• Rigid MCM PWBs shall meet the requirements of LAT Procurement Specification, LAT-DS-01127-01 based on Mil-PRF-55110, Revision F, and GSFC S-312-P-003 with a minimum internal annular ring of 0.002”.

• Flex circuit and cables shall meet requirement of LAT-PS-01132 and IPC 6013 class 3. Coupons shall be submitted to GSFC for evaluation.


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Electronic Packaging ProgramElectronic Packaging Program

• PWB Coupon will be analyzed by GSFC prior to flight assembly.

• Particular attention will be paid to the quality of workmanship, soldering, welding, wiring, marking of parts and assemblies, plating and painting.

• Verification of flight hardware will be performed by NASA certified and qualified personnel other than the original operator.

• An item inspection will be performed on each component to verify:– Configuration is as specified on each component

drawing/specification.– Workmanship standards have been met.– Test results are acceptable


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ASIC and MCM Documentation StatusASIC and MCM Documentation Status

• Wafer Procurement from MOSIS / Agilent

– LAT-PS-1279: Overview

– LAT-PS-1201: Front-end readout chip (GTFE) approved by PCB

– LAT-PS-1222: Readout controller chip (GTRC) approved by PCB

– LAT-PS-1250: wafer probing, review in process

– LAT-PS-01321: wafer lapping, dicing, and inspection, review in process.

– LAT-TD-1325: Radiation testing, to be reviewed.

• Several other documents such as MCM assembly, SMT assembly, part procurements are in draft format and shall be released by CDR.

• Final board prototypes were recently produced and are being tested:

– PWB: loaded with parts and new ASICs for functional testing

– Pitch Adapter: Teledyne is bonding 3 of them to MCMs to check that the new design works

– Bias: sent to Italy for review


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EEE Parts Issues & Risk MitigationEEE Parts Issues & Risk Mitigation

• MCM board qualification and handling.– To mitigate this risk, processes, procedures, qualification

plan, and vendor verification plan is in process and will ensure they are implemented successfully.

• Pitch adapter flex gluing and alignment accuracy when bonding to PWB.– To mitigate this risk, processes will be verified and

controls will be implemented at Teledyne.• Flight ASICs testing

– To mitigate this risk, all processes and procedures are being approved. Test software is being improved, which will be used for verification.

• MCM Assembly and Verification– To mitigate this risk, manufacturing readiness reviews will

be performed and mandatory inspection points will be selected.


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EEE Parts Issues & Risk MitigationEEE Parts Issues & Risk Mitigation

• Flex Cable to LAT-PS-01132, defines procurement and qualification requirements.– To mitigate this risk EM flex cable will be manufactured to

this specification and will be qualified.– A visit to the vendor (Parlex) is planned for early April,

together with GSFC representatives.• Flex Cable Assembly.

– To mitigate risk a detailed procedure being written & EM flex will be assembled and will be tested prior to flight production.

• Radiation Testing & Plans– To mitigate risk GSFC is involved in approving plans but

radiation plans yet not approved.


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ConnectorsConnectors

• Nano-connectors: Omnetics was recently approved and the parts are now on order, including the connector savers.

• Micro-D connectors: Kristek connectors are not yet approved, but we don’t expect any difficult issues.

On MCM

On cable

Larger 080 screws


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SMT PartsSMT Parts

• HV capacitors: Novacap

– Procurement spec: LAT-PS-01194

– On order for the Tracker and Calorimeter

• Polyswitches: Raychem (Tycho)

– Procurement spec: LAT-SS-01116

– A sample lot was already procured and all testing performed, so no surprised are expected in the flight lot

– Recently finalized and approved, and the parts are on order

– Long process of testing at UCSC and discussions with the vendor

• 100% of parts: screening after thermal cycle

• 10% of parts: more extensive tests after soldering

• Smaller sample for qualification testing at UCSC

• Ceramic & tantalum capacitors: approved with no issues

• Resistors: approved with no issues

• Thermistor: approved with no issues


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Manufacturing and Test Process Flow Manufacturing and Test Process Flow for Tracker Hardwarefor Tracker Hardware

Pre-Production Procurement Fabrication Assembly

-Initial Quality Planning-Design Reviews-Critical Components-Documentation Reviews-Lessons Learned-Quality Criteria-Design Requirements-Workmanship Standard-Training and Certification

-Pre-award surveys-Supplier Evaluation-Purchase Document Review-Source inspection where applicable-Critical Components-Nonconforming Material Control

-Manufacturing Reviews-Work instructions and procedures-Calibration-Process Readiness-Nonconforming Material Control-Inspection-Material Review Board-Audits

-Work instructions, procedures, and travellers-Audits-Configuration verification-Inspection

Integration & Test

-Test Readiness Review-Nonconforming material control- Previous Operation Audits-Component Data/Subsystem packages-Test Procedures-Test Monitoring-Data Review-Closeout of open NCMRs.

Storage & Shipping

-Storage and Shipping Requirements-Inspection and storage shipping controls-Data Package Reviews-Audits

Documents

GLAST LAT ProjectTKR Peer Design Review, Mar 24-25, 2003 5BNick Virmani 1 GLAST Large Area Telescope Tracker Subsystem Gamma-ray Large Area Space Telescope