GLAST LAT Project March 24, 2003
6F Tracker Peer Review, WBS 4.1.4 1
GLAST Large Area Telescope:GLAST Large Area Telescope:
Tracker SubsystemWBS 4.1.4
6F: Tray assembly
A. BrezI.N.F.N. Pisa
Gamma-ray Large Gamma-ray Large Area Space Area Space TelescopeTelescope
GLAST LAT Project March 24, 2003
6F Tracker Peer Review, WBS 4.1.4 2
MCM Assembly on Trays and Test (INFN)
Procedure doc: LAT-PS-01802MCM incoming test: • Read out tests • Noise level• Noisy channels• HV test
MCM assembly with glue and screws Scotchweld 2216 A/B grayGlue thickness .1mmPattern of glue lines to avoid air trapping
Area occupancy 50% ∼ ⇨ Δt 0.1≲ 0CMCM final test: • Read out tests • Noise level• Noisy channels• HV test
The tray is put in the tray-storage box and is delivered to the ladder assembly center
GLAST LAT Project March 24, 2003
6F Tracker Peer Review, WBS 4.1.4 3
Integration of SSD Ladders onto Tracker TraysIntegration of SSD Ladders onto Tracker Trays
Assembly in G&A Engineering
Assembling stepsAssembling steps• Tray position study, Z adjustment• The ladders are aligned on the
alignment jig• The ladders are vacuum kept by the
bridges• The glue drops are deposited on the
tray• The tray is placed again on the tool• The ladders are positioned on the tray
by means of the bridges• Glue cure (at RT for more than 6 hours)• Ladder metrology• Microbonding• MCMs fast test to check bondings• Encapsulation• The tray is placed in the tray-storage
box for delivery to test labs
• Tray position study, Z adjustment• The ladders are aligned on the
alignment jig• The ladders are vacuum kept by the
bridges• The glue drops are deposited on the
tray• The tray is placed again on the tool• The ladders are positioned on the tray
by means of the bridges• Glue cure (at RT for more than 6 hours)• Ladder metrology• Microbonding• MCMs fast test to check bondings• Encapsulation• The tray is placed in the tray-storage
box for delivery to test labs
Procedure doc: LAT-PS-01801
GLAST LAT Project March 24, 2003
6F Tracker Peer Review, WBS 4.1.4 4
The toolsThe tools
Jig of ladders alignment
Ladders vacuum kept on the bridges
Jig of tray alignment
Reference dowels
Alignment micrometers
C.M.M. with touch head and optical head
All the assembly operations under C.M.M.Glue spots deposition with automatic dispenserMicrobonding with automatic wedge bonder
GLAST LAT Project March 24, 2003
6F Tracker Peer Review, WBS 4.1.4 5
Assembly phasesAssembly phases
Tray positioning
Ladder positioning
Microbonding
1 assembly chain ready5 assembly chains in constructionMax assembly rate : 15 trays/weekForeseen assembly rate: 10 trays/week
GLAST LAT Project March 24, 2003
6F Tracker Peer Review, WBS 4.1.4 6
Connector savers
Fixation screws
The tray storage box
This robust Aluminum box allows safe and clean shipping.The tray can be tested in the closed box, connecting the MCMs through the connector savers.
Connector saver protections
GLAST LAT Project March 24, 2003
6F Tracker Peer Review, WBS 4.1.4 7
First resultsFirst results
ladder alignemnt
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
m
=14m
TG02 dw
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0 100 200 300 400
Y (mm)
Z (m
m)
x=47
x=231
x=404
glue pads 5mmcure time 6h
Planarity
Requirements:Alignment error < 40mPlanarity 100m
GLAST LAT Project March 24, 2003
6F Tracker Peer Review, WBS 4.1.4 8
ConclusionsConclusions
• The tray assembly has been successfully tested: the alignment and planarity of the ladders are in specification with possible improvements.
• The number of tools in production will allow an assembly rate of 40 trays/month (2 towers/month) that well matches with the test rate of the trays and towers.