Process for preparing backside passivation layer of monocrystal silicon solar battery plate by laser rapid heating method

The invention discloses a process for preparing a backside passivation layer of a monocrystal silicon solar battery plate by a laser rapid heating method. The process comprises the following steps of: generating a barrier layer on an illuminated face of the battery plate by plasma enhanced chemical vapor deposition (PECVD), and then printing a layer of aluminum paste on a backlight surface of the battery plate; roasting the battery plate printed with the aluminum paste, and removing a dissolvent in the aluminum paste; and finally, performing laser irradiation on the aluminum paste to ensure that aluminum is molten rapidly and diffused into a battery plate matrix, and forming a P+ layer. In the process, the aluminum paste is heated by laser, and then the aluminum is completely diffused into the battery plate matrix under the action of the laser, so that the battery plate is prevented from being warped after the traditional aluminum back surface field is sintered; at the same time, the doped concentration is hi