From: Rabbi Moshe Sofer
To: Rabbi Meshulam
A Sefer Torah had the word 'Elokeinu' written with the nun extended and the vav separated, rendering it invalid. The Chasam Sofer rules that if the vav is clearly separated, it is not appended to the Divine Name and may be erased directly; if unclear, the vav must be physically excised (kadur) from the parchment and placed in genizah rather than erased, since erasure of a possibly appended letter poses a potential Biblical prohibition.
Source: Shu"t Chasam Sofer YD §263