K.K. GanUS ATLAS Review1 Optical Hybrids K.K. Gan The Ohio State University WBS

K.K. GanUS ATLAS Review2 Outline l Introduction l Opto-package prototypes l Opto-hybrid board design l Cost and schedule summary l Conclusions

K.K. GanUS ATLAS Review3 ATLAS Pixel Opto-link

K.K. GanUS ATLAS Review4 l 2 fibres + VCSEL + PIN l coupled VCSEL power > 300  10 mA l VCSEL tolerance: l 50  m in z (along fibre) l 25  m in r (transverse to fibre) Opto-package

K.K. GanUS ATLAS Review5 l Marconi P 8 silicon/alumina pieces P use silicon mirror for 45 0 light reflection P high cost l Taiwan P 3 G-10 pieces P cleave fibre at 45 0 P fibers permanently attached: need voliton connector P low cost l OSU P 2 pieces P cap with fibers can be attached to package at end of module assembly P low cost Opto-package Designs

K.K. GanUS ATLAS Review6 l connector concept design P use precisely fabricated cap and base for alignment P simple two-piece design for mass production and cost reduction l cap P 2 holes for fibers l base P deposit gold traces for wire bonding, VCSEL and PIN placements OSU Design

K.K. GanUS ATLAS Review7 Base and Cap

K.K. GanUS ATLAS Review8 l produced caps and bases (rounded corners) using machinable ceramic P material tested: aluminum silicate and macor P difficult to obtain consistent precision  redesign base with square corners for ease of fabrication by Hybrid-Tek P alumina sheet ground to proper thickness and cut into strips P have produced bases with precision within specification P 3D traces have good connectivity  fabricate cap with Ultem (polyetherimide) for radiation tolerance (10 Grad) P use manual micro mold injection to save development time P can fabricate several quality caps per hour Cap and Base Prototypes

K.K. GanUS ATLAS Review9 l produced 10 packages l VCSELs have fast rise and fall time: < 1 ns l PINs have good responsitivity: 0.5 A/W l coupled power > 300  W in both VCSELs simultaneously for 8 packages with different combinations of bases and caps  demonstrated feasibility of fabricating high precision caps and bases l no cross-talk between VCSEL and PIN above 20  Prototype Result

K.K. GanUS ATLAS Review10 Cap with Precisely Fabricated Cavity

K.K. GanUS ATLAS Review11 Base with PIN and VCSELs

K.K. GanUS ATLAS Review12 Completed Opto-package

K.K. GanUS ATLAS Review13

K.K. GanUS ATLAS Review14 no cross talk above 20  A

K.K. GanUS ATLAS Review15 l principle of two-piece connector concept demonstrated P precision bases with 3D traces of good connectivity fabricated P precision caps fabricated  packages produce optical power above specification  negligible cross-talk between VCSEL and PIN l ability to produce precise die placement jig is a concern P required six trials (one week) for current jig Summary on Opto-package

K.K. GanUS ATLAS Review16 l convert optical signal into electrical signal and vice verse l contains 6 sets of opto-pack, VDC, and DORIC l electrical signal to/from module channel through 60-pin connector l layout to serve 7 modules is ready P will convert to serve 6 modules P first submission will use FR-4 for cost saving P 2nd and 3rd prototypes will use BeO l board is compatible with Taiwan opto-pack Opto-hybrid Board

K.K. GanUS ATLAS Review17 Opto-hybrid

K.K. GanUS ATLAS Review18

K.K. GanUS ATLAS Review19

K.K. GanUS ATLAS Review20 l principle of fabrication of opto-pack demonstrated l no major technical challenge in opto-hybrid board fabrication P compatible with Taiwan opto-pack P experience in opto-pack prototyping is very useful for mounting opto-packs on opto-hybrid board Conclusions