I wonder whether there is any way to create a DOI for a paper that was uploaded to arXiv but not published somewhere else, and have the DOI points to the arXiv URL (e.g., not pointing to some researchgateresearchgate page). While there are reasons that arXiv does not provide DOIs (Why does arxiv.org not assign DOIs?Why does arxiv.org not assign DOIs?), I prefer to use the same identifiers for all my research papers.