CN2415520Y

CN2415520Y - Heat Source isolated controllable electric conductivity vertical cavity surface emitting laser

Info

Publication number: CN2415520Y
Application number: CN 00231062
Authority: CN
Inventors: 程澎; 林世鸣
Original assignee: Laboratory Of Semiconductor Inst National Joink Key Laboratory About Integrated
Current assignee: Laboratory Of Semiconductor Inst National Joink Key Laboratory About Integrated
Priority date: 2000-04-05
Filing date: 2000-04-05
Publication date: 2001-01-17
Anticipated expiration: 2010-04-05

Abstract

The utility model relates to a heat source isolated electric conductivity controllable vertical cavity surface emitting laser. A substrate of the utility model is a lower electrode, an N-type DBR is arranged on the substrate and is an active region, a P-type DBR is arranged on the active region, and an upper electrode is arranged at the top part of the P-type DBR, wherein, an insulation layer is arranged at the middle of the active region, so the active region can be divided into a transversal current-conducting channel and a lower active region which are stopped by the low resistivity; one side of the insulation layer which is far away from the P-type DBR is correspondingly provided with an electric-conducting hole region; the P-type DBR of the upper side is arranged at the upper part of the active region, which corresponds to a vertical position of axial direction of the electric-conducting hole region. The utility model conquers the problem that an element is seriously exothermic when the electrode is injected from the top part, and the utility model avoids the problem that fabrication process is complicated when the electrode is injected from the side direction. The utility model has the advantages that the product performance can be guaranteed, and the electric conductivity can be controlled and adjusted.

Description

The vertical cavity surface emitting laser of isolated power supply, controllable electric conductivity

The utility model relates to a kind of vertical cavity surface emitting laser, especially a kind of vertical cavity surface emitting laser of thermal source being kept apart and can the regulating and controlling conductance.

Vertical cavity surface emitting laser is called for short VCSEL.VCSEL is that Japanese Iga is taught in 1977 proposition first.This is a kind of a kind of new construction of conventional semiconductors side-emitted laser different from the past, and excellent characteristic was studied widely and used in today with its uniqueness.Existing vertical cavity surface emitting laser vcsel structure basic comprising comprises Prague transmitting mirror (DBR) of P type, the DBR of active area and N type.P type DBR provides the conduction region in a hole, and as a minute surface of laser.The DBR of N type provides the conduction region of an electronics, and as another minute surface of laser.In active area, hole and electron recombination are luminous, vertically produce laser.Substantially be divided into two classes, a class is as shown in Figure 1, and substrate is for 4 times a bottom electrode 6, and substrate 4 is provided with N type DBR3, and N type DBR3 goes up to active area 2, is P type DBR1 on the active area 2, and top electrode 5 is arranged on P type DBR1 top.Electric current 7 is injected into active area 2 by P type DBR1, and active area 2 produces light, by P type DBR1 vertical output laser beam.In this spline structure, because the DBR1 that electric current will distribute through the P type of a high resistant, therefore heating is more serious, and heating can reduce the performance of device greatly.Another kind of is that side is injected, and as shown in Figure 2, the basic layer structure is with shown in Figure 1 identical, and just top electrode 8,8 ' corrosion are arranged on the both sides of P type DBR1.The problem that the mode that this side direction is injected exists is: its electrode is often made difficulty on the one hand, and ohmic contact is relatively poor, and the lateral resistance of active area 2 is a fixed value, and is generally higher, can't regulate, and in addition, the current efficiency that side direction is injected is not high.The development that these factor one straight obstacles vertical cavity surface emitting laser, shortcomings such as vertical cavity surface emitting laser ubiquity power is low, life-span weak point.

The purpose of this utility model is to provide at the deficiency of prior art a kind of vertical cavity surface emitting laser of isolated power supply, controllable electric conductivity, it had both overcome the problem of the serious device heating of top injecting electrode formula, avoided side direction injecting electrode complex manufacturing technology problem again, guarantee properties of product, and can the regulating and controlling conductance.

The purpose of this utility model is achieved in that a kind of vertical cavity surface emitting laser of isolated power supply, controllable electric conductivity, its substrate is bottom electrode down, substrate is provided with N type DBR, N type DBR goes up and is active area, on the active area P type DBR, top electrode is arranged on P type DBR top, be provided with an insulating barrier in the middle of the wherein said active area, active area is divided into horizontal flow-guiding channel and the following active area that low-resistivity ends, insulating barrier is offered the conduction porose area away from P type DBR one side correspondence, and the active area top of the axial upright position of corresponding conduction porose area is provided with upside P type DBR.

Described insulating barrier can be oxidized resistive formation.

Be provided with insulating barrier between described interconnection top, the two P type DBR, insulating barrier top is provided with the grid of external voltage.

Described interconnection can be high electron mobility transistor structure.

The interconnection of described low-resistivity medium can be P type high doped materials layer.

According to the technique scheme analysis as can be known, the utlity model has following advantage:

1, electrode still is produced on the P type DBR, but the injection direction of P type dbr current and luminous active area are separated in the horizontal, not same axially on, but by the interconnection water conservancy diversion, active area and DBR heat is produced to be unlikely to influence each other, thereby reduce the heating of product greatly, improved properties of product.

2, increase grid, realized the purpose that conductance is controlled, and by correspondent control circuits, can constitute closed-loop system for the control of laser, thereby obtain more stable output valve, satisfy different actual requirements.

3, in the horizontal communication of P type DBR injection region and active injection region, use High Electron Mobility Transistor (HEMT) technology, not only make the efficient of laterally injecting improve greatly, and this electrical efficiency can be controlled more neatly.

Below in conjunction with accompanying drawing and specific embodiments the utility model is described in further detail.

Fig. 1 is a kind of prior art constructions schematic diagram;

Fig. 2 is another kind of prior art constructions schematic diagram;

Fig. 3 is a structural representation of the present utility model;

Fig. 4 is the utility model horizontal communication high electron mobility transistor structure layer schematic diagram.

Referring to Fig. 3, the utility model is a kind of vertical cavity surface emitting laser of isolated power supply, controllable electric conductivity, its substrate is for 4 times a bottom electrode 6, substrate 4 is provided with N type DBR3, N type DBR3 goes up to active area 2, is an oxidized high resistance insulating barrier 10 on the active area 2, is the horizontal flow-guiding channel layer 9 of low resistance on the high resistance insulating barrier 10, insulating barrier 10 is offered conduction porose area 11 away from P type DBR1 one side correspondence, and active area 2 tops of corresponding conduction porose area 11 axial upright positions are provided with upside P type DBR12.Top electrode 5 is arranged on P type DBR1 top, electric current 7 from power on the utmost point in P type DBR1, inject downwards again, because the iris action of high resistance insulating barrier 10, the electric current 7 horizontal flow-guiding channel layer 9 of low-resistance medium of flowing through, to active area 2, active area 2 is luminous by insulating barrier 10 conduction porose areas 11, the N type DBR3 below electric current 7 flows to.Light beam is then launched vertically upward through insulating barrier 10 conduction porose areas 11, because the upside P type DBR12 effect on the correspondence position produces laser beam.The DBR1 that electric current 7 is flowed through and the active area 2 that produces light source and the P type DBR12 lateral separation that produces laser beam like this, isolated thermal source, active area 2 and DBR1 heat produce and no longer influence each other, greatly reduce the heat accumulation in luminous, solve the problem of vertical cavity surface emitting laser heating, improved the performance of product.

As shown in Figure 3, for the efficient of Control current injection or the resistivity of control low-resistance region, be provided with oxide insulating layer 13 between interconnection layer 9 top, two P type DBR1, the DBR12, oxide insulating layer 13 tops are provided with grid 14, grid 14 voltages can come from external control circuit, can control the resistance and the electric current of interconnection layer 9 as grid 14, simultaneously because the setting of grid 14 also can realize the closed-loop control of whole device.

In order to improve the control to interconnection layer 9 resistance and electric current more effectively, interconnection layer 9 adopts high electron mobility transistor structures, i.e. HEMT structure, as shown in Figure 4.It is the plain material layer 92 of low energy gap of material layer 91 sandwich by a broad stopband doping (N type or P type).Because the effect at interface, when making alive on grid 14, the charge carrier that height in the wide-band gap material layer 91 is mixed enters in the small gap material layer 92 that does not mix up, because small gap material undopes, so charge carrier moves therein very high mobility can be arranged, again owing to the high charge carrier of mixing in the material enters in this material, so carrier concentration is very high in the wide-band gap material layer 91, resistance ratio is less, and current ratio is bigger.Whole interconnection layer 9 can be the repetition overlaying structure of material sandwich one deck small gap material layer 92 of (N type or P type) in one deck wide-band gap material layer 91.Improve the efficient of horizontal injection like this, controlled whole device electrical efficiency flexibly, easily.

Claims

1, a kind of vertical cavity surface emitting laser of isolated power supply, controllable electric conductivity, its substrate is bottom electrode down, substrate is provided with N type DBR, N type DBR goes up and is active area, on the active area P type DBR, top electrode is arranged on P type DBR top, it is characterized in that: be provided with an insulating barrier in the middle of the described active area, active area is divided into horizontal flow-guiding channel of low resistance and following active area, insulating barrier is offered the conduction porose area away from P type DBR one side correspondence, and the active area top of the axial upright position of corresponding conduction porose area is provided with upside P type DBR.

2, the vertical cavity surface emitting laser of isolated power supply, controllable electric conductivity according to claim 1 is characterized in that: the oxidized resistive formation of described insulating barrier.

3, the vertical cavity surface emitting laser of isolated power supply, controllable electric conductivity according to claim 1 is characterized in that: be provided with insulating barrier between described interconnection top, the two P type DBR, insulating barrier top is provided with the grid of external voltage.

4, the vertical cavity surface emitting laser of isolated power supply, controllable electric conductivity according to claim 1 is characterized in that: the interconnection of described low-resistivity medium can be high electron mobility transistor structure.

5, the vertical cavity surface emitting laser of isolated power supply, controllable electric conductivity according to claim 1 is characterized in that: the interconnection of described low-resistivity medium can be P type high doped materials layer.