Ageing Studies of synthetic materials for the ATLAS Silicon Strip Endcap Upgrade

Introduction

This page documents the performance of ageing studies related to the upgrade of the ATLAS Silicon Strip Endcap detector. Synthetic materials like PET, POM, PMMA, Kapton, ... and several glues or coating material (cured, uncured and their individual components) such as Hysol, Epolyte, Silver epoxy ..., are subjected to high temperatures over a long period of time. These materials are placed in small boxes together with bonded ASIC chips, so that the ageing can be studied both in terms of changes in its physical shape as well as the effect on its disintegrating on nearby electronics. For this purpose a photo documentation is kept.

The samples and the chips are placed inside small glass bottles, which are then place inside a laboratory oven.

Materials tested

synthetic solids: Polyethylene terephthalate (PET), Polypropylene (PP), Polyvinyl chloride (PVC), Polyurethan (PUR) hose, Nylon, Kapton, (PMMA), Hybrid, PLA, cellulose acetate, Teflon, (POM), Polyethylene (PE), Acrylonitrile butadiene styrene (ABS)

coating materials: Polyurethan (PUR), Sylgrad 186

glues: Epolyte, Hysol, silver epoxy, 3525, 3013, 6621, SE4445,

Sylgrad 186, Epolyte, Hysol, silver epoxy and SE4445 are tested in the cured state, as well as their individual components in liquid state.

3525, 3013, 6621 are tested in cured and uncured state

The samples are placed inside alu block containers, each able to hold 6x6 samples. The setup of the materials inside the containers can be found in the table attached to this page (setup.pdf).

Examples:

• Samples of kapton, cured hysol and the base component of silver epoxy, each placed inside a glass bottle with a wire-bonded ASIC chip:
  

The samples will remain in the oven for temperatures starting at 60 degrees and going up to 150 degrees for considerable amount of times (30 days per temperature). 2 sets of samples are removed monthly for a photo documentation and placed back in the oven. Those sets will stay in the oven for the entire experiment. The individual samples will be removed when damaged or when the safety temperature limit has been reached for a particular material. For T=60 and T=70, the experiment will run with all samples.

Photo documentation

The following links contain the full photo documentation of all the samples as they are processed. Batch 1 and batch 2 are two sets of samples that are meant to remain in the experiment as temperatures are increased, only removed when unsafe temperatures are reached and/or the tested material gets damaged

Batch 1 10Jan2018Batch1 09Feb2018Batch1 16Mar2018Batch1 27Apr2018Batch1 01Jun2018Batch1

Batch 2 10Jan2018Batch2 09Feb2018Batch2 16Mar2018Batch2 27Apr2018Batch2 01Jun2018Batch2

One batch of samples is kept at room temperature outside the oven throughout the whole experiment for reference

room temperature batch 10Jan2018RoomT

T=60 batch (T60) 10Jan2018T60 09Feb2018T60

T=70 batch (T70) 09Feb2018T70 16Mar2018T70

T=80 batch (T80) 16Mar2018T80 27Apr2018T80

T=90 batch (T90) 27Apr2018T90 01Jun2018T90

T=100 batch (T100) 01Jun2018T100C

Timeline

10 Jan 2018 16:45 : Batch 1 and 2 and the T60 set are placed inside the oven at a stable temperature of 60 degrees.

09 Feb 2018 09:30 : batch 2 is removed from oven for the photo documentation. Placed back at 10:00

09 Feb 2018 10:00 : batch 1 is removed from oven for the photo documentation. Placed back at 10:30

09 Feb 2018 10:30 : The T60 samples is removed from the oven and replaced with a new set (T70). The temperature is raised to 70 degrees.

09 Feb update:

solid samples suffered no modifications under 60 degrees. the ASIC chips are intact. Some physical changes observed for the epolyte and the hysol curing agents:

-- DidierAlexandre - 2018-02-01

• before (left) and after (right) pictures of the epolyte curing agent. Picture on the right taken after 30 days under 60 degrees.:
  

• Before (left) and after (right) pictures of the curing agent. Picture on the right taken after 30 days under 60 degrees.: