Large smile, the emitters in a laser diode are vertically displaced, is always a big obstacle to affect the directly application of high power laser diode. In this report, a symmetrical structure, that bonding two submounts on the top and bottom of heat sink to control the smile effect by balancing the packaging induced stress, is designed. A cm bar with less than 1 um smile value delivering more than 200W continuous wave (CW) mode output power with power conversion efficiency (PCE) 65% is reported. The lifetime can reach more than 20000 hours. We also report the applications of high power and low smile vertically stacked laser bars, like forming a wider line for glass surface treatment and a rectangular beam for cladding. A 2x14mm2 rectangular beam was built with 32 bars vertical stack to produce 6kW CW mode output power with a beam uniformity of more than 80%. © 2019 SPIE.