Background: I'm a statistician working with a design of experiments example regarding plasma etching of circuits, and unfortunately, the author does not define what is meant by the units used for the etch rate ($\mathring{A}$/min). A google search has proved fruitless due to the specialized symbol and the fact that other texts also assume you already know what the $\mathring{A}$ symbol means (which is probably true for those who work in this field, but not for the rest of us).
Question: What does the $\mathring{A}$ unit mean in a plasma etching experiment, for "Etch rate ($\mathring{A}$/min)."