Abstract: An embodiment of the present invention discloses a camera actuator comprising: a housing; a mover on which an optical member sits and which is disposed inside the housing; a ball part including a first ball and a second ball and disposed between the housing and the mover; and a driving unit that is disposed inside the housing to drive the mover, wherein the mover includes a first protrusion extending toward the housing and including a recess. The recess includes: a side surface on which the ball part sits and on which at least a portion of the recess is spaced apart from the ball part; and a bottom surface in contact with the side surface.

Abstract: A cleaning solution for preventing the collapse of photoresist patterns and a method of cleaning a semiconductor device using the cleaning solution; the cleaning solution includes a solvent and a surfactant and has a dynamic surface tension of about 50 dyne/cm or less at about 6 bubbles/seconds when measured by a maximum bubble pressure method. The collapse of the photoresist pattern can be prevented using the cleaning solution when forming minute photoresist patterns having about 100 nm or less pattern width. The cleaning solution containing a surfactant in a high concentration also can be prepared to reduce distribution expenses.