Is there any way to add a custom field that can attach Service Type to an Incident Ticket (similar to the Incident Area field)?
You could probably add column to the CR (call request) object as a reference to the service types table, and add a field to the incident detail form to populate that field, however, the functionality behind how service types work and what they drive would not work in this case because there are no triggers available to invoke that functionality outside of the automated way of having service types attached to categories/areas. Something like this would be a bit outside of what the ITIL standards are for incident handling, as service types should be automatically applied and should never be changed through the life of a ticket, as they drive metrics - thus doing so would allow metrics to be "skewed" to some extent by changing the service types, thus affecting the expectations for specific incident areas/services. Now thats not to say this could not be done with some custom code, but unfortunately that would be outside the scope of support and would not be something we could assist you with.
Hope this helps.
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