The Wall Street Journal reports that Apple has placed orders for key components to be used in next-generation’s iPhone to prepare for a third quarter launch.

The newer version of iPhone is expected to be thinner and lighter than the iPhone 4 and said to have an 8-mega pixel camer. The iPhone will operate with Qualcomm Inc.’s wireless baseband chips, a person familiar with the matter tells the Wall Street Journal.

A source at one of Apple’s suppliers says the company is looking to meet its goal of 25M units by the end of this year-2011. Apple said it sold 18.65 million iPhones in the fiscal second quarter, which ended March 26. Last month after returning from a trip to Taiwan, Morgan Stanley analyst Katy Huberty said Apple will commence production on the next version of the iPhone this August.

Shipments of the new iPhone could be delayed if Hon Hai can’t improve its yield rate as the new iPhone is “complicated and difficult to assemble, the WSJ says.