Camera.clearFlags
var clearFlags: CameraClearFlags;
Description

How the camera clears the background.

Can be CameraClearFlags.Skybox, CameraClearFlags.SolidColor, CameraClearFlags.Depth or CameraClearFlags.Nothing.
	// Clear with background color (ignore any skyboxes)
	camera.clearFlags = CameraClearFlags.SolidColor;