When a high-quality company has a fall, it's usually a good buying opportunity.Shares of semiconductor equipment leader ASML Holdings (ASML 2.50%) plummeted 16.7% this week through Thursday trading, according to data from S&P Global Market Intelligence.ASML made news on Tuesday when it accidentally leaked its earnings report a day early, causing the big decline. But it wasn't the early nature of the leak that took the stock down, or really the reported revenue and profits. Rather, it was the bookings figure ...