The average selling price of those chips fell 23 percent in the first quarter from the prior period.The company also makes Nand flash memory chips, used in digital cameras and portable devices such as the iPhone and iPad.Shipments of those products rose 20 percent, while prices fell 15 percent, Micron said.Micron fell 2.4 percent to US$8.08 in extended trading after rising US$0.14 to US$8.28 at 4p