We have no built-in support for Bamboo and ServiceNow, neither an Atlassian marketplace plugin for it, as thinks seem to stand.

Could we have steps to integrate Bamboo and service now .

1. Using webhooks :- Use native functionality such as Bamboo Webhooks to interact with Service Now APIs, final tasks that execute a script and interact with SN via the REST APIs

2. Email Notificstion :- You could also probably even setup Bamboo to send an email notification and then have SN monitor that inbox and create a ticket, before proceeding with the deployment.