Fiber laser cuts small text on aluminum foil

How small a text can be cut well on a piece of kitchen aluminum foil? We use a 30w fiber laser with 290mm lens. Text is "BAKE" in the picture cut in one pass. Smaller than 2mm overall length, the "E" becomes a rectangle. A narrower font can do better, but it looks like line. If power is too high, the aluminum will vaporize. Although aluminum dissipate heat quickly, this foil is thin. For small island area, the heat can build up. For example, consider the following picture: when laser is cutting the top part of the white area, heat can flow to the bottom part. When the laser is cutting the bottom part, heat cannot flow to the separated part; when the area is small, the problem becomes more apparent. Corner 2 will not be as clean as corner 1.

White: material. Black: nothing.