The
following questions were asked in order to evoke a discussion between the participants:
Can we standardize
- measurement procedures ?
- test structures ?
- irradiation procedures ?
- annealing procedures ?
Iris:
What counts in the end is the signal to noise ratio in your specific experimental
environment with your specific type of detector. This has to be tested before the
implementation of the full detector as close as possible to realistic situations. To only
perform standardized tests could hinder the development of optimized solutions.
Renate/Jonas:
The radiation environments in the different experiments are not too different.
Thus standardization should be done where it can be done in order to allow for comparisons
between different experiments. The success we had in the field of radiation damage had not
been possible without the standardizations we already use, like the fluence normalization
to 1 MeV neutrons. This is only one example that shows that standardizations are usefull,
at least up to a certain level..
Alberto:
It is astonishing that the uncertainties of "standard silicon" as
presented in the talk of Michael and investigated by ROSE are not leading to the formation
of another research collaboration dealing with this topic. Especially in the few of future
detector projects this is for sure necessary. Are such R&D projects foreseen at CERN?
Christian/Tapio:
The discussion about future R&D projects working on the development of new
and/or radiation harder detector concepts is presently going on in the CERN management.
However, for the moment such activities are not foreseen and therefore a reanimation of
R&D projects is not expected before the end of this year.
Luciano:
It is not possible to put standard diodes on all wafers. A strict standardization
is not possible since it takes the freedom for producing something new.
Iris:
A compilation of recommended test structures should be made available on a
www-page of an institution like the former ROSE
collaboration or a detector support group at e.g. CERN. In this case the experiments
could decide whether they want to use the structures or not.
Wolfram:
Besides a compilation of recommended test structures a compilation of recommended
measurement techniques and measurement procedures should be included in such a database.
Iris:
The measurement procedure for most detectors could be "standardized".
Alexander:
The workshop is a big success since it brought together people from different
experiments and even more from experiments in different phases of the production of a
silicon detector. It was a good platform to exchange problems and experiences and was for
sure helpful. It should be repeated.
Erik:
The experiments should not only state that this workshop was helpful to them but
they should also take some action. They should make their mind up whether they want
further meetings like this one in order to exchange knowledge and experiences between the
experiments. This kind of meeting is not restricted to silicon detector quality assurance
topics but could also be useful to other subdetector components of experiments. If they
think it is useful they have to ask the management for the implementation of regular
workshops.
Will we have a further workshop ?
All participants agreed that the workshop was useful. Thus, a further workshop should
be arranged. However, it should earliest take place in 1-2 years when he LHC-experiments
can report about their success and problems about implementing quality assurance and
quality control in their detector construction process.
Further comments:
Paolo
This workshop was announced as a workshop on quality assurance issues in silicon
detectors. However, the terms of QA, QC and QM were often used improperly. This will lead
to confusions when you communicate with experts in this field.