The ABC130 barrel module prototyping programme for the ATLAS strip tracker

Abstract

silicon pixel, silicon strip and transition radiation sub-detectors, will be replaced with an all new 100 % silicon tracker, composed of a pixel tracker at inner radii and a strip tracker at outer radii. The future ATLAS strip tracker will include 11,000 silicon sensor modules in the central region (barrel) and 7,000 modules in the forward region (end-caps), which are foreseen to be constructed over a period of 3.5 years. The construction of each module consists of a series of assembly and quality control steps, which were engineered to be identical for all production sites. In order to develop the tooling and procedures for assembly and testing of these modules, two series of major prototyping programs were conducted: an early program using readout chips designed using a 250 nm fabrication process (ABCN-250) [2, 3] and a subsequent program using a follow-up chip set made using 130 nm processing (ABC130 and HCC130 chips). This second generation of readout chips was used for an extensive prototyping program that produced around 100 barrel-type modules and contributed significantly to the development of the final module layout. This paper gives an overview of the components used in ABC130 barrel modules, their assembly procedure and findings resulting from their tests.

A Starry Byte -- proton beam measurements of single event upsets and other radiation effects in ABCStar ASIC Versions 0 and 1 for the ITk strip tracker

“…The analogue currents remain constant at approximately 70 mA, regardless of the radiation dose delivered to the ASIC. This is consistent with what was observed for ABC130 ASICs [6]. The digital currents see an initial increase in current, reaching a maximum of 140 mA at 1 Mrad before decreasing to 60 mA at higher doses.…”

“…During the December beam test, where two new ABCStar V1 ASICs (273 and 274) were irradiated alongside two previously tested ASICs (259 and 267), a comparable current measurement shows a similar increase of the digital current for the new ASICs, as shown in figure 10b). The two previously irradiated ASICs show a digital current increase much lower than the unirradiated ASICs, confirming the effect of pre-irradiation on the TID bump observed for ABC130 ASICs [6]. The piece-wise behaviour of the digital current curves is a result of stopping/starting data collection runs.…”

Magnetic triggering — time-resolved characterisation of silicon strip modules in the presence of switching DC-DC converters

“…complied with module performance requirements [2], but are smeared over the full range of latencies between DC-DC switching and triggering and therefore average over any time-dependent effects. Since the noise increase was assumed to be caused by the EMI noise emitted from the DC-DC circuitry, an additional time-resolved study of the observed noise increase and the DC-DC switching was performed.…”

Silicon strip defects and their impact on electrical performance of readout electronics

“…The assembly procedures follow closely those described in ref. [13]. For the miniaturized sensors, four ABCStar chips and one HCCStar chip were glued onto a prototype hybrid made of low-mass flexible copper-polyimide PCB.…”