| 1 |
< |
\section{The Silicon Strip Tracker Components} |
| 1 |
> |
\section{The TIB/TID Components} |
| 2 |
|
\label{sec:Components} |
| 3 |
< |
In this section the main SST components, with special attention |
| 4 |
< |
to the TIB ones, will be described. Detailed description will be made for items which are |
| 3 |
> |
Full views of a finished half of the TIB and a TID Disk are shown in Fig.~\ref{fig:tibtid}. |
| 4 |
> |
|
| 5 |
> |
This section describes the main TIB and TID components: detailed description will be made for items which are |
| 6 |
|
of particular importance for the integration activities, both for assemblies and tests. |
| 7 |
|
|
| 8 |
< |
\subsection{TIB Mechanics and Cooling} |
| 8 |
> |
\begin{figure}[!htb] |
| 9 |
> |
\begin{center} |
| 10 |
> |
\includegraphics[height=0.5\textwidth]{Figs/TIB-assembled.pdf} |
| 11 |
> |
\includegraphics[width=0.5\textwidth, angle=90]{Figs/TID-disk.pdf} |
| 12 |
> |
\end{center} |
| 13 |
> |
\caption{Half of TIB assembled and one TID disk on the left and on the right respectively. The 4 shells |
| 14 |
> |
structure is visible for the TIB; the 3 rings structure is visible for the Disk.} |
| 15 |
> |
\label{fig:tibtid} % Give a unique label |
| 16 |
> |
\end{figure} |
| 17 |
> |
|
| 18 |
> |
Table~\ref{table:layers} summarize the number of the different components for the several layers/rings |
| 19 |
> |
of the TIB/TID. |
| 20 |
> |
|
| 21 |
> |
\begin{table}[!htb] |
| 22 |
> |
\begin{center} |
| 23 |
> |
\begin{tabular}{|l||c|c|c|c|c|c|c|} |
| 24 |
> |
\hline |
| 25 |
> |
Layer & \# mechanical & \# cooling & DS/SS & \# of modules & \# of channels & \# Control & \# Mother \\ |
| 26 |
> |
& structures & circuits & layer & total & per module & Rings & Cables \\ |
| 27 |
> |
\hline |
| 28 |
> |
\hline |
| 29 |
> |
TIB L1 & 4 shells & & DS & & & & \\ |
| 30 |
> |
TIB L2 & 4 shells & & DS & & & & \\ |
| 31 |
> |
TIB L3 & 4 shells & & SS & & & & \\ |
| 32 |
> |
TIB L4 & 4 shells & & SS & & & & \\ |
| 33 |
> |
TID R1 & 6 rings & 24 & DS & 288 & 768 & 12 & 48 \\ |
| 34 |
> |
TID R2 & 6 rings & 24 & DS & 288 & 768 & 12 & 48 \\ |
| 35 |
> |
TID R3 & 6 rings & 24 & SS & 240 & 512 & 12 & 48 \\ |
| 36 |
> |
\hline |
| 37 |
> |
\end{tabular} |
| 38 |
> |
\caption[smallcaption]{ Details on the different layers/rings of the TIB/TID. } |
| 39 |
> |
\label{table:layers} |
| 40 |
> |
\end{center} |
| 41 |
> |
\end{table} |
| 42 |
> |
|
| 43 |
> |
|
| 44 |
> |
\subsection{Mechanical Structures} |
| 45 |
|
|
| 46 |
|
The TIB support structure was designed structured as 4 concentric layers |
| 47 |
|
and realized using mainly carbon fiber. Each of these layers |
| 48 |
|
is made up of four half-cylinder (called "shells") |
| 49 |
< |
being splitted vertically at $z=0$ and horizontally at $y=0$.\\ |
| 50 |
< |
The shell includes all the services: it has a network of cooling pipes covering both its |
| 51 |
< |
external and its internal surface. Aluminium circuits are bent into loops and soldered |
| 52 |
< |
to inlet/outlet manifolds near the shell front flange, |
| 53 |
< |
which connect several loops together. The thermal connection |
| 54 |
< |
between pipes and detector modules is made with Aluminium ledges which are |
| 55 |
< |
precisely glued |
| 56 |
< |
on the carbon fiber support structure and in good thermal contact with the pipes. |
| 49 |
> |
being split vertically at $z=0$ and horizontally at $y=0$. |
| 50 |
> |
Each shell hosts services both on its external and its internal surface. |
| 51 |
> |
Modules and associated services, that are on the same side of a shell and at the same $\phi$ coordinate |
| 52 |
> |
constitute a \textit{string}. |
| 53 |
> |
%A TIB shell is shown on Fig.~\ref{fig:tibshell}). |
| 54 |
> |
|
| 55 |
> |
%Each cooling loop hosts three modules placed in a straight row, which is called a |
| 56 |
> |
%A string of modules is connected to the same CCU, thus forming a control branch. |
| 57 |
> |
|
| 58 |
> |
%\begin{figure} |
| 59 |
> |
%\centering |
| 60 |
> |
%\includegraphics[width=\textwidth]{ } |
| 61 |
> |
%\caption{TIB shell: are visible the internal and external parts, the cooling pipes and the string} |
| 62 |
> |
%\label{fig:tibshell} |
| 63 |
> |
%\end{figure} |
| 64 |
> |
|
| 65 |
> |
The 6 TID disks are all identical and each one is made out of three rings. Each ring consists of |
| 66 |
> |
a support mechanical structure made of an annular carbon fiber honeycomb, hosting modules and services on both sides to decrease the density and therefore providing a better accessibility during ring integration and disk assembly. |
| 67 |
> |
|
| 68 |
> |
Each TID+ and TID- is obtained by inserting, positioning and fixing each disk into a carbon fiber cylinder called {\it Service Cylinder}. Each Service Cylinder has several holes at the position of disk, in order to allow the connection of the power lines and to route out all the fibers of the disk. The service Cylinder is also used to connect mechanically TIB+/- and TID+/-, |
| 69 |
> |
and to route out the services of the TIB and of the TID. |
| 70 |
> |
|
| 71 |
> |
%\begin{figure} |
| 72 |
> |
%\centering |
| 73 |
> |
%\includegraphics[width=\textwidth]{ } |
| 74 |
> |
%\caption{TID ring } |
| 75 |
> |
%\label{fig:tidring} |
| 76 |
> |
%\end{figure} |
| 77 |
> |
|
| 78 |
> |
|
| 79 |
> |
The cooling in the TIB/TID is distributed via aluminum circuits called cooling pipes |
| 80 |
> |
that are bent into loops and soldered to inlet/outlet manifolds near a large flange. |
| 81 |
> |
The thermal connection between pipes and sensor modules is made with Aluminum ledges which are |
| 82 |
> |
precisely glued on the carbon fiber support structure and in good thermal contact with the pipes. |
| 83 |
|
On each ledge there are two threaded M1 holes onto which the modules are tightened. |
| 84 |
|
Precisely drilled slots, coaxial with the threaded holes, are the reference point where |
| 85 |
< |
insets are stick in providing mechanical reference for modules (see Fig.~\ref{fig:module_cooling}). |
| 85 |
> |
insets are stick in providing mechanical reference for modules. An example for a TIB module |
| 86 |
> |
is shown in Fig.~\ref{fig:module_cooling}). |
| 87 |
> |
|
| 88 |
> |
|
| 89 |
|
\begin{figure} |
| 90 |
|
\centering |
| 91 |
|
\includegraphics[width=\textwidth]{Figs/module_cooling.pdf} |
| 92 |
< |
\caption{TIB cooling. |
| 92 |
> |
\caption{Module Cooling . |
| 93 |
|
\textbf{Upper picture:} a whole cooling loop with six ledges to hold three modules and three |
| 94 |
|
smaller ledges to hold Analog Opto-Hybrids (two more cooling loops are partially visible). |
| 95 |
|
\textbf{Lower picture:} a detail of a cooling loop. The cooling fluid direction |
| 98 |
|
\label{fig:module_cooling} |
| 99 |
|
\end{figure} |
| 100 |
|
|
| 35 |
– |
Each cooling loop hosts three modules placed in a straight row, which is called a \textit{string}. |
| 36 |
– |
%A string of modules is connected to the same CCU, thus forming a control branch. |
| 101 |
|
|
| 102 |
< |
\subsection{The Detector Module} |
| 103 |
< |
The detector module design has been kept as simple as possible to ease their |
| 104 |
< |
mass production and integration. The silicon sensor~\cite{ref:mask}\cite{ref:sensors} |
| 105 |
< |
is glued on a carbon fibre support |
| 42 |
< |
frame which also holds the front-end electronics hybrid. The sensor is alligned, during its |
| 43 |
< |
gluing, using a reference system made by the frame aluminum insets. Since the insets are the |
| 44 |
< |
reference points to mount the module on the shell, this choice guarantee the best reproducibility |
| 102 |
> |
\subsection{The Silicon Module} |
| 103 |
> |
The silicon module design has been kept as simple as possible to ease their |
| 104 |
> |
mass production and integration. In TIB and TID the module hosts a single silicon sensor~\cite{ref:mask}\cite{ref:sensors} glued on a carbon fiber support |
| 105 |
> |
frame which also holds the front-end electronics hybrid. The sensor is aligned with respect to the same frame aluminum insets that are used to mount the module on the shell: this choice guarantee the best reproducibility |
| 106 |
|
of the sensor position in the global shell coordinate system.\\ |
| 107 |
|
The readout chip |
| 108 |
|
pitch (44$\mu$m) is matched to the sensor pitch via an aluminum deposited glass substrate |
| 110 |
|
adapter). The hybrid circuit, which houses the front-end chips and ancillary |
| 111 |
|
electronics, is realized using kapton multilayer technology integrating the power and |
| 112 |
|
signal cables. \\ |
| 113 |
< |
Figure \ref{fig:moduless} and \ref{fig:moduleds} show a TIB single and double-sided module |
| 114 |
< |
respectively. |
| 113 |
> |
Fig~\ref{fig:moduless} and \ref{fig:moduleds} show a TIB single and double-sided module |
| 114 |
> |
respectively. Fig.~\ref{fig:moduletid} show a R1 TID module. |
| 115 |
> |
|
| 116 |
> |
{\it Commento LD: Dobbiamo aggiungere delle foto di tutte le geometrie ? |
| 117 |
> |
} |
| 118 |
> |
|
| 119 |
|
|
| 120 |
|
\begin{figure}[!htb] |
| 121 |
|
\begin{center} |
| 133 |
|
\label{fig:moduleds} % Give a unique label |
| 134 |
|
\end{figure} |
| 135 |
|
|
| 136 |
+ |
\begin{figure}[!htb] |
| 137 |
+ |
\begin{center} |
| 138 |
+ |
\includegraphics[height=0.60\textwidth,angle=90]{Figs/module-R1.pdf} |
| 139 |
+ |
\end{center} |
| 140 |
+ |
\caption{ A ring 1 TID module.} |
| 141 |
+ |
\label{fig:moduletid} |
| 142 |
+ |
\end{figure} |
| 143 |
|
|
| 144 |
< |
Detectors of the TIB, TID, and of the four innermost rings of the TEC have |
| 145 |
< |
strip lengths of approximately 12 cm and pitches between 80 $\mu$m and 120 $\mu$m. |
| 146 |
< |
These detectors are made of a single sensor 320 $\mu$m thick. In the outer part |
| 147 |
< |
of the tracker (TOB and three outermost TEC rings) strip length and pitch |
| 148 |
< |
are increased by about a factor of two with respect to the inner ones. In order |
| 149 |
< |
to compensate for the noise increase due to the higher inter-strip capacitance |
| 150 |
< |
(longer strips), a silicon thickness of 500 $\mu$m has been chosen for these larger |
| 151 |
< |
detectors. \\ |
| 152 |
< |
All Silicon Strip Sensors are of single sided type and produced from $<100>$ |
| 153 |
< |
Float-zone type 6 inches wafers. |
| 154 |
< |
Double sided detectors are |
| 144 |
> |
|
| 145 |
> |
Sensors of the TIB and TID have respectivelly strip lengths of 12 cm and between 9 and 11 cm for TID, are 320 $\mu$m thick |
| 146 |
> |
%{\it verify these lenghts } |
| 147 |
> |
%and of the four innermost rings of the TEC |
| 148 |
> |
and pitches vary between 80 $\mu$m and 120 $\mu$m. |
| 149 |
> |
%These silicon are made of a single sensor 320 $\mu$m thick. |
| 150 |
> |
|
| 151 |
> |
% LD: is this relevant for the TIB/TID integration paper ? |
| 152 |
> |
% ========================================================== |
| 153 |
> |
% In the outer part |
| 154 |
> |
%of the tracker (TOB and three outermost TEC rings) strip length and pitch |
| 155 |
> |
%are increased by about a factor of two with respect to the inner ones. In order |
| 156 |
> |
%to compensate for the noise increase due to the higher inter-strip capacitance |
| 157 |
> |
%(longer strips), a silicon thickness of 500 $\mu$m has been chosen for these larger |
| 158 |
> |
%detectors. \\ |
| 159 |
> |
|
| 160 |
> |
%All Silicon Strip Sensors are of single sided type and produced from $<100>$ |
| 161 |
> |
%Float-zone type 6 inches wafers. |
| 162 |
> |
|
| 163 |
> |
Double sided modules are |
| 164 |
|
realized simply gluing back to back two independent single sided modules: to |
| 165 |
|
obtain a coarser but adequate resolution on the longitudinal coordinate the so |
| 166 |
|
called “Stereo” module has the sensor tilted of 100mrad with respect to the |
| 167 |
|
“R-Phi” one. The “Stereo” sensor and electronics are identical to the “R-Phi” |
| 168 |
|
ones, the only difference being in the support mechanics and pitch adapters. |
| 88 |
– |
To reduce problems due to the radiation damage of the Silicon Strip Sensors |
| 89 |
– |
the Detector modules will be cooled to a temperature which, on the Silicon Sensor, |
| 90 |
– |
will reach about -10$^\circ C$.\\ |
| 169 |
|
|
| 170 |
< |
\subsection{The Front-end Electronics} |
| 170 |
> |
% LD: is this relevant for the integration paper ? |
| 171 |
> |
% ================================================== |
| 172 |
> |
%To reduce problems due to the radiation damage of the Silicon Strip Sensors |
| 173 |
> |
%the Detector modules will be cooled to a temperature which, on the Silicon Sensor, |
| 174 |
> |
%will reach about -10$^\circ C$.\\ |
| 175 |
> |
|
| 176 |
> |
%\subsection{The Front-end Electronics} |
| 177 |
|
The signals coming from each strip are processed by front-end readout chips |
| 178 |
|
(APV25) mounted on the multilayer kapton hybrid circuit. The APV25~\cite{ref:apv} |
| 179 |
|
is a 128 channel chip built in radiation hard 0.25 $\mu$m |
| 202 |
|
which is located |
| 203 |
|
on the hybrid circuit too. |
| 204 |
|
Since the chip may not output data for a considerable time when it is waiting for a trigger, |
| 205 |
< |
it is necessary for the DAQ electronics to remain synchronised with the APV25 |
| 205 |
> |
it is necessary for the DAQ electronics to remain synchronized with the APV25 |
| 206 |
|
when it eventually begins to read out data. To allow for this |
| 207 |
< |
the chip outputs a synchronisation pulse, of 25ns duration, called a 'tick mark' every |
| 207 |
> |
the chip outputs a synchronization pulse, of 25ns duration, called a 'tick mark' every |
| 208 |
|
70 clock cycles when there is no data to read out. |
| 209 |
|
The APV25 electrical signals are then converted to optical |
| 210 |
|
ones in dedicated Analog-Opto Hybrids (AOH\cite{ref:aoh}) few centimeters away from |
| 211 |
< |
the detector, and transmitted to the counting room by means of multi-mode |
| 212 |
< |
optical fibres~\cite{ref:opto}, where they are digitized~\cite{ref:fed}. |
| 211 |
> |
the module, and transmitted to the counting room by means of multi-mode |
| 212 |
> |
optical fibers~\cite{ref:opto}, where they are digitized~\cite{ref:fed}. |
| 213 |
|
The LHC 40MHz clock, which |
| 214 |
|
drives the APV25 sampling can be delayed at the single module level by |
| 215 |
|
means of a PLL (phase lock loop) chip\cite{ref:pll} to take into account the |
| 220 |
|
two constant current sources and a temperature sensor. It |
| 221 |
|
monitors two sets of thermistors, one on the sensor |
| 222 |
|
and one on the hybrid, its own internal temperature, the |
| 223 |
< |
silicon detector bias current and the two (1.25 V and |
| 223 |
> |
silicon sensor bias current and the two (1.25 V and |
| 224 |
|
2.5 V) low voltages.\\ |
| 225 |
|
Each DCU has a unique hardware identification |
| 226 |
|
number (called \textit{DCU Hardware ID}) that can also be read through the $I^2C$ interface. |
| 229 |
|
stores the module information, |
| 230 |
|
and the online databases, storing information during data taking. |
| 231 |
|
|
| 232 |
< |
\subsection{The off-detector Electronics} |
| 232 |
> |
\subsection{The off-Module Electronics} |
| 233 |
|
\subsubsection{AOH} |
| 234 |
|
|
| 235 |
|
The electric to optical conversion is done by radiation hard lasers~\cite{Gill:2005ui}. |
| 236 |
|
These devices sit on a dedicated board, called Analog Opto-Hybrid, which is |
| 237 |
< |
fixed on a ledge glued on the cooling pipe very close to the detector module. |
| 237 |
> |
fixed on a ledge glued on the cooling pipe very close to the silicon module. |
| 238 |
|
The electrical signals arrive to the AOH through the module front-end hybrid |
| 239 |
|
kapton cable tail which carries the AOH power lines too. |
| 240 |
|
The AOH can hold up to three lasers (only two are mounted for single sided 4 APV chips |
| 242 |
|
The on-board control logic is used to drive the lasers: it has an $I^2C$ |
| 243 |
|
control register for each laser |
| 244 |
|
which is split in a 2-bit section (GAIN: 0$\div$3) and a 7-bit section (BIAS: 0$\div$127). |
| 245 |
< |
The GAIN value can be used to compensate the loss of signal on the fibre link |
| 245 |
> |
The GAIN value can be used to compensate the loss of signal on the fiber link |
| 246 |
|
and optical connections from AOHs to FEDs. |
| 247 |
|
During normal operation, if no damage was done to the line and ideal connections, |
| 248 |
|
it is normally set to 1. The actual gain |
| 249 |
|
of the AOH is not proportional to the GAIN parameter, as the four |
| 250 |
< |
possible nominal gains are: 0.5, 0.75, 1, 1.25 (normalised w.r.t. GAIN=3). |
| 250 |
> |
possible nominal gains are: 0.5, 0.75, 1, 1.25 (normalized w.r.t. GAIN=3). |
| 251 |
|
The BIAS parameter regulates the current threshold for the laser diodes. |
| 252 |
|
Its optimal value strongly depends on temperature and also on irradiation. |
| 253 |
|
|
| 254 |
+ |
Each AOH has two (single sided modules) or three (double sided modules) |
| 255 |
+ |
two meter long pig-tail optical fibres ending with a connector |
| 256 |
+ |
|
| 257 |
|
\subsubsection{CCU} |
| 258 |
|
|
| 259 |
< |
The Silicon Strip Tracker Detector Modules are controlled by a set of signals |
| 259 |
> |
{\it manca referenza } |
| 260 |
> |
|
| 261 |
> |
The module electronics is controlled by a set of signals |
| 262 |
|
(clock, trigger, $I^2C$ lines) which are dispatched to them via a |
| 263 |
< |
token ring strucured circuitry ("control ring"). |
| 263 |
> |
token ring structured circuitry ("control ring"). |
| 264 |
|
CCUs are the nodes of this structure. They receive instructions from the external |
| 265 |
|
FEC (front-End Controller) |
| 266 |
|
either directed to themselves or to the $I^2C$ devices connected to them. The first case is used |
| 267 |
|
for example to read the Status Register of the CCU or to raise its output PIA reset lines. |
| 268 |
|
While in the latter case |
| 269 |
|
commands are translated to the $I^2C$ protocol and forwarded to the |
| 270 |
< |
other devices located on the detector modules or AOH; in case of |
| 270 |
> |
other devices located on the sensor modules or AOH; in case of |
| 271 |
|
a reply from the $I^2C$ device, the reverse process is done by the CCU, which addresses the |
| 272 |
|
information to the FEC. |
| 273 |
|
The CCU device sits on a CCU-Module (or CCUM) which carries also buffering chips and a DCU. |
| 275 |
|
|
| 276 |
|
\subsubsection{Mother Cable} |
| 277 |
|
|
| 278 |
< |
In the TIB a multi-layer kapton copper cable ("Mother Cable", see Fig.~\ref{fig:fotomc}) |
| 278 |
> |
{\it manca referenza } |
| 279 |
> |
|
| 280 |
> |
|
| 281 |
> |
In the TIB/TID a multi-layer kapton copper cable ("Mother Cable", see Fig.~\ref{fig:fotomc}) |
| 282 |
|
is mounted on the carbon fiber shell underneath the |
| 283 |
< |
modules. It carries the $I^2C$ serial data (SDA) |
| 283 |
> |
modules. A full description of the mother-cable can be found in~\cite{ref:mc}. |
| 284 |
> |
|
| 285 |
> |
It carries the $I^2C$ serial data (SDA) |
| 286 |
|
and clock (SCL) lines, |
| 287 |
|
a hard reset (PIA reset) line and the |
| 288 |
|
LHC clock for each module. CCUs in the TIB can be connected to 3 or 6 modules\footnote{Actually |
| 289 |
|
to 3 single-sided or double-sided modules, but to the Control System point of view a |
| 290 |
< |
double-sided module is seen as a pair of independent modules.}. |
| 290 |
> |
double-sided module is seen as a pair of independent modules.} while for TID are connected to |
| 291 |
> |
6 modules (3 double-side modules) for R1 and R2 and to 5 modules for R3. |
| 292 |
|
|
| 293 |
|
\begin{figure} |
| 294 |
|
\begin{center} |
| 300 |
|
\end{figure} |
| 301 |
|
Moreover this cable is used to power the modules (1.25~V, 2.5~V, high voltage bias line and |
| 302 |
|
common return).\\ |
| 303 |
< |
The mother cable hosts a socket to hold the CCU module, three connectors |
| 304 |
< |
for the low voltage lines, HV lines and the token ring cable. Each module is served by a couple |
| 305 |
< |
of connectors (LV \& $I^2C$ and HV). A CCU and the modules connected to the |
| 306 |
< |
same mother cable are called a \textit{string}. |
| 303 |
> |
The mother cable receives LV and HV power for the modules, power and signals for the CCU, via three sockets located at the edge; then hosts a socket to hold and feed the CCU module and serves each module with a couple |
| 304 |
> |
of connectors (LV \& $I^2C$ and HV). |
| 305 |
> |
|
| 306 |
> |
For the TIB one mother cable serves a full string, while for the TID serves a 90 degrees sector. |
| 307 |
> |
|
| 308 |
|
|
| 309 |
|
%%%%%%%%%% qui l'ho un po' cambiato. C.G. |
| 310 |
|
%\subsubsection{DOH} |
| 313 |
|
|
| 314 |
|
\subsubsection{Control Ring} |
| 315 |
|
\label{fig:ctrlring} |
| 316 |
< |
A control ring is an electro-optical circuitry that interfaces the detector to the |
| 316 |
> |
|
| 317 |
> |
{\it manca referenza } |
| 318 |
> |
|
| 319 |
> |
A control ring is an electro-optical circuitry that interfaces the front-end electronics to the |
| 320 |
|
tracker control system. |
| 321 |
|
The control ring is optically driven by a FEC (Front-End Controller) module~\cite{ref:opto} |
| 322 |
|
located outside the tracker in the experiment control room. |
| 324 |
|
electrical signals by two DOHs |
| 325 |
|
(Digital Opto-Hybrid) that |
| 326 |
|
send clock, trigger, and control signals to the token ring of CCUs. |
| 327 |
< |
The DOHs are physically located on a board (DOHM) that provides up to 15 ports |
| 327 |
> |
The DOHs are physically located on a board (DOHM~\cite{ref:dohm}) that provides up to 15 ports |
| 328 |
|
(7 on the main DOHM board plus 8 on its |
| 329 |
|
secondary extension or AUX) to implement the token ring. Each port |
| 330 |
|
connects the DOHM or the AUX to a CCU located on the Mother Cable head via a 26 poles flat cable. |
