Process Design And Preparation Of 1060nm Tunnel Cascaded Multi-active Region High Power Semiconductor Laser

At present,1060 nm lasers are widely used,such as laser ranging,laser medical treatment,etc.,but most of them use solid-state lasers such as Nd:YAG,which are generally large in size and usually weigh from several kilograms to several tens of kilograms.In recent years,short-distance ranging and aiming systems are developing with high power and miniaturization,requiring 1060 nm lasers with high efficiency,small size and narrow divergence angle.The small size,high conversion efficiency,and low cost of semiconductor lasers make it possible to study 1060 nm semiconductor lasers instead of solid-state lasers.Therefore,a high-power and high-efficiency multiactive region tunnel cascaded 1060 nm semiconductor laser is proposed and prepared,and a mini bar is prepared to increase the maximum output power of the device.The main work of this paper is as follows:1.Optimize the epitaxial structure of the tunnel cascaded semiconductor laser.The optical field and refractive index distribution of the asymmetric large-cavity epitaxial structure are simulated.The epitaxial structure adopts a 1.4?m asymmetric large cavity structure,which increases the effective spot size,reduces the far-field divergence angle,improves the COD threshold power,and suppresses the high-order mode generation.,reduce internal losses.The double quantum wells are introduced into the tunnel junction,and the tunnel junction device before and after optimization are prepared,which proves that the reverse bias resistance of the device is lower after optimization.2.The fabrication process design of 1060 nm tunnel cascaded multi-active region semiconductor laser.Starting from improving device power,solving COD,electrothermal burnout,and current and carrier lateral expansion,according to the established process flow,the design of isolation double groove,ridge table,electrode window,cleavage line and cavity surface coating process are designed,respectively.In order to keep the device small size,it is proposed to prepare a mini bar to further increase the power and design the layout.3.Process optimization for 1060 nm tunnel cascaded multi-active region semiconductor laser.The cleaning,lithography,etching,ICP,sputtering,alloy annealing,sintering and packaging processes are optimized,and an optimized process is used to separate the double groove,the ridge table,the electrode window and the chip electrode,and the width of the light-emitting unit is 200 ?m.The lateral period is 500 ?m,and the cavity surface is coated after cleavage into a cm strip with a cavity length of 1mm.The reflectance of the antireflection film and the high reflective film are 10.5% and 98.5%,respectively.After the cleavage chip,the chip p faces down.Sintered on a C-mount heat sink and packaged onto a TO3 header.4.Testing 1060 nm tunnel cascaded multi-active region semiconductor lasers and mini-bars.Pulse test at room temperature,pulse width 20 ?s,frequency 20 Hz.The double active region laser has a power of 16.71 W at a current of 17.5 A.The triple active region laser has a power of 19.26 W at a current of 12 A.The 1.5 mm mini bar device has a power of 47.76 W at 28 A.The results show that the use of lateral tunnel cascaded multiple active regions and lateral mini-bar structures is an effective way to increase the output power of semiconductor lasers and reduce the volume.