Ⅱ-9. Instrumentation

RIKEN Accel. Prog. Rep. 53

Assembly of Intermediate Silicon Tracker in Taiwan
C. Shih,∗3 Y. Akiba,∗1 D. Cacace,∗2 K. Cheng,∗3 E. Desmond,∗2 T. Hachiya,∗1,∗4 S. Hasegawa,∗5 T. Kondo,∗6C. Kuo,∗3 M. Lenz,∗2 E. Mannel,∗2 C. Miraval,∗2 M. Morita,∗4 I. Nakagawa,∗1 R. Nouicer,∗2 R. Pisani,∗2
M. Shibata,∗4 A. Suzuki,∗4 T. Todoroki,∗1 X. Wei,∗7 and R. Xiao∗7
The INTermediate Tracker (INTT) is the tracker
system between the Time Projection Chamber (TPC)and the MAPS-based Vertex Detector (MVTX). INTT
makes up the gap between TPC and MVTX, it can precisely reconstruct the track of charge particles. OneINTT ladder consists of 59 components, 1 stave, 2-highdensity interconnects (HDIs), 52 readout chips and 4 silicon sensors. All the components will be ﬁxed by glueand screws. A ladder assembly is performed in the following sequence. 1), Fix the readout chip on HDI bysilver epoxy with 26 chips per HDI. 2), Bond the readout chips to HDI using a bonding machine and checkthe response to slow control commands in a test bench.
3), assemble HDI with readout chips onto stave by thermal glue and screws. 4), Assemble silicon sensors onto
the ladder by silver epoxy. 5), Bond the silicon sensors toreadout chips by a bonding machine and check the FPHX
response again and also silicon sensor performance. 6),
Apply an encapsulation to protect the bonding wires.
The National Central University (NCU) in Taiwan is responsible for one-third of the INTT ladder production.
The assembly procedures 1) and 2) are planned to becovered by a private company in Taiwan, and the remaining procedures will be conducted in a clean-room
facility at the National Taiwan University (NTU). Figure 1 shows the gantry to be used for the assembly inNTU, which consists of a large ﬂat table with a fourdimensional robotic gantry head. The gantry head isequipped with an optical microscope, which allows a calibration error in position to be the order of 10 µm. Thusfar, the assembly procedure requires 9 tools, as shown

Fig. 1. Photo of the clean room in NTU. Gantry, bonding
machine and optical gaging products (OGP) microscope
are all available.
∗1
∗2
∗3
∗4
∗5∗6∗7

RIKEN Nishina CenterBrookhaven National Laboratory
National Central University
Nara Women’s University
Japan Atomic Energy Agency
Tokyo Metropolitan Industrial Technology Research InstitutePurdue UniversityFig. 2. The designs of the prototype of INTT ladder assembly
tools, the assembly tools family.

Fig. 3. Assembly tools already fabricated by AS CNC.

in Fig. 2. The assembly unit is one ladder, and thedesigns of all prototype assembly tools have been completed. The idea is to assemble the entire ladder on theladder assembly tray, while HDIs and silicon sensors areplaced on the HDI sample tray and sensor sample trayby hand, respectively. Pick up tools are used to pick up
the HDI and silicon sensors via the vacuum system andmove them to the stave by the gantry. An order for thetools has already been submitted to the Academia Sinica(AS) computer numerical control (CNC) factory. The
production of 5 has been completed, as shown in Fig. 3.
The assembly exercise and bonding exercise are scheduled to start simultaneously in early March. A dummy
HDI, dummy silicon sensor, and dummy stave have alsobeen produced, which are suﬃcient for the exercise. Two
important aspects namely, the type of glue and the procedure to apply the glue, are uncertain and need to bedetermined. Both are expected to be ﬁnalized at theend of March. A new INTT test bench has been set up
in NCU, and a few checks are to be made to be fully
functional.
The conclusion for the INTT assembly in Taiwan isthat we aim to provide one functional complete ladderfor INTT phase - 3 Test Beam at 22th April.
References

1) Conceptual Design Report of sPHENIX (2018).
2) The PHENIX Forward Silicon Vertex Detector.

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