CN1267108A - Electronic Bragg reflector and its application in LED - Google Patents

Abstract

An electronic Bragg reflector is made by alternatively laminating two kinds of semiconductor layers containing different components. The thickness of layers are gradually decreased. Said electronic Bragg reflector can be used in LED by arranging it between core layer and P layer, to increase the lumious efficiency of yellow light by using Ga-Al-In-P material in MOCVD device and to develop green LEDs.

Description

Electronic Bragg reflector and the application in light-emitting diode thereof

The present invention relates to semiconductor device, particularly have the light emitting semiconductor device of a jump in potential potential barrier or surface potential barrier at least.Particularly, it is the electronic Bragg reflector that forms with the artificial superlattice of semi-conducting material, and be used for light emitting semiconductor device, particularly light-emitting diode and visible light semiconductor laser, comprise green glow, blue light or more in short wavelength's the light emitting semiconductor device to injecting the operative constraint and the control of electronics, and can be used for the device that other need retrain and control the electron transport process.

Opto-electronic device particularly for light-emitting diode and this class luminescent device of semiconductor laser, requires can both to be limited in active (active layer) to injected electrons (n-type charge carrier) and space (p-type charge carrier) and distinguishes, and recombination luminescence there.The key of device success is respectively to the effective constraint and the utilization of photon and electronics.Typical constraint to electronics the earliest is a double heterojunction.Heterojunction be by two kinds of semiconductors that different energy gaps are arranged in conjunction with and form.On faying face, the energy gap difference forms a potential barrier, and different according to mixing, and can realize the constraint to electronics and space respectively.The semiconductor forbidden band that is clipped in the middle is narrow more, and the energy gap of both sides covering is wide more, and this constraint is just more effective.Usually the semiconductor laser operation wavelength of communication usefulness is at 1550nm or 1300nm, and the energy gap that launching this wavelength needs is respectively 0.8 and 0.95 electron-volt (eV).In order to obtain the material of this class energy gap, available gallium, indium, arsenic, phosphorus alloy are regulated component and are reached.Form the wide bandgap material alloy material that adds aluminium commonly used of covering.For example the band gap of gallium aluminum arsenide alloy material can be used formula Eg=1.42+1.14X+0.5X ²Calculate.Therefore, be easy to obtain 0.4eV or higher potential barrier and realize operative constraint electronics.It has been generally acknowledged that, be acceptable barrier height more than or equal to 0.2eV.Potential barrier is low, and device lowly can not be used because of charge carrier loss luminous efficiency.

Have only lattice match or lattice constant identical materials epitaxial growth to form heterojunction.Lattice match requires to reach ten thousand/.In order to obtain the restriction of higher barrier, it is that barrier layer is approached that a kind of structure is arranged.For example in gallium aluminium indium phosphorus quaternary material, utilize 1% tensile stress layer, aluminium content is brought up to 0.65, like this, interface potential barrier can improve 0.03eV, the good result of being launched the 5700A green-yellow light efficiently again.But, with the gallium aluminium indium phosphorus direct band gap of GaAs lattice match from fluorescence Spectra, can arrive 5500A, should reach 5390A from direct band gap estimation, so about this wavelength of also arriving with the luminescent device minimal wave length of gallium aluminium indium phosphorus quaternary system work.Shorter wavelength will lean on III-V family nitrogen-containing compound, or material such as II-VI compounds of group, for example at present the light-emitting diodes of green glow and blue streak effective be nitrogenous III-V compounds of group, this class material technology difficulty is big, production cost is higher, among the research that much the problem still exists; Produce nitrilo compound in addition and want higher growth temperature, thereby special equipment will be arranged.So the blue streak light-emitting diode that can buy or its processed goods are still very expensive.The work that exploitation is blue, green light emitting device is still present great commercial value.

Adopting Bragg reflection for the constraint of light has been very common thing.The distributed feedback semiconductor laser that makes with photoetching method and Bragg reflection surface luminous semiconductor laser and the light-emitting diode made of epitaxy method all are very successful.That is the application of success of the fluctuation of light.The application of electronic wave in device yet there are no report.

It is the fact that proves already that electronics has fluctuation, utilizes the metal mineral crystal to prove that the electron reflection intensity of certain speed is relevant with lattice constant as far back as 1921-23, repellel maximum and minimum value occurs, is similar to the Bragg reflection in the wave mechanics.The lattice constant that cycle that can occur according to the maximum of electron reflection and corresponding electron accelerating voltage (being certain velocity of electrons) calculate crystal.But because lattice is very serious to the scattering of free electron, it is very shallow that penetration of electrons enters the degree of depth of crystals, generally all will and adopt the diffraction of high-order to prove the Bragg reflection of electronics with higher accelerating voltage.The division that the motion of electronics in periodic field causes being with in semiconductor, form conduction band and forbidden band.In semiconductor, add artificial period meshes, and added electric field quickens to electronics, provide condition for utilizing electronic wave.

The objective of the invention is to the defective at the prior art existence, a kind of electronic Bragg reflector is provided, this electronic Bragg reflector adopts artificial superlattice structure, realizes constraint and control to electronics.

The present invention also aims to provide the application process of a kind of electronic Bragg reflector in light-emitting diode, when the luminescent device emission wavelength when the shortwave direction is expanded, when injecting electronic motion as be not enough to restriction when potential barrier of heterogenous junction, the constraint of electronics is provided, thereby improves the efficient of luminescent device.For example, improve the luminous efficiency of present Yellow light emitting device for gallium aluminium indium phosphorus series material, and to the expansion of short wavelength's direction, the exploitation green device.

Various Bragg reflectors are not the natural lattices that utilizes semi-conducting material in semiconductor, but artificial superlattice, be according to the light wavelength that will reflect, select for use the material of two kinds of different refractivities to calculate the required actual geometric thickness of actual quarter-wave light path, the multi-layer film structure that the refractive index that produces just replaces, be used for semiconductor laser device for communication in a large number, as the reflector of photon, successfully realized constraint in surface luminous semiconductor laser and the superhigh brightness LED to photon.This artificial periodic structure is called superlattice.

Modern age thin film fabrication technology, particularly MOCVD (Chinese is: Metalorganic chemical vapor deposition) equipment has been created condition for making super crystal lattice material.The thickness of grown layer can accomplish that large tracts of land is even in the precision of 0.1 nanometer, different materials when growth lattice mismatch can accomplish less than ten thousand/.Present light-emitting diode is also made with the MOCVD technology, and normally double-heterostructure or double heterojunction add the quantum well structure, and the Bragg reflection structure that has increased light is also arranged, and that is the uniform period structure that one of four parts of emission wavelengths thickness thin layer forms.The present invention proposes the non-homogeneous periodic structure to electron reflection, promptly the cycle is called the Chirp Bragg catoptric arrangement by the structure of successively decreasing or progressive law changes.

The present invention is with the Bragg reflection of superlattice realization to electronics.Will be according to the artificial superlattice of device operating voltage design, and can make this superlattice with the MOCVD technology, realize the electronic Bragg reflection, this is a kind of new method that realizes for injecting electron confinement.

Electronic Bragg reflector of the present invention forms by the semiconductor material layer of two kinds of heterogeneities is alternately folded mutually, and the thickness of material successively decreases respectively, and the varied in thickness cycle successively decreases by the periodic law of manually warbling simultaneously.

This structure reflects the electron energy distributions that is in the electric field.Can produce this periodic structure of manually warbling with program control MOCVD technology.

The used semi-conducting material of electronic Bragg reflector of the present invention is the general semi-conducting material of prior art, for example gallium aluminium indium phosphorus series semiconductor material.

Fig. 1 a, Fig. 1 b are electronic Bragg reflector operation principle schematic diagrames of the present invention.Wherein Fig. 1 a is that the interface that the injection electronics is crossed than low potential barrier enters the B district schematic diagram of indirect transition band gap; Fig. 1 b is the schematic diagram that the distribution of the periodic structure generation of warbling in B district is reflected in the relevant superposition formation electronics standing wave of A district and incident electron ripple.As shown in Figure 1a, under effect of electric field, flow into the electronics in direct transition A district ● can cross heterojunction boundary and can getable potential barrier enter the B district of indirect transition band gap because of materials limitations, through non-radiative compound, the minimizing on luminous efficiency rank going along with reduces rapidly.Shown in Fig. 1 b, the electronics that is accelerated ● the increase de Broglie wavelength with energy reduces, and on corresponding artificial chirp structure, produce the Bragg reflection that distributes; The distributed Blatt reflective ripple (rr) of transmission is through twice quarter-wave time delay, and it closes ripple (RR) and transmitted wave (T) and keeps the phase shift mutually of л disappear superposition and very fast disappearance; The ripple (R) that closes of reverse distribution reflection (r) forms standing wave to the relevant superposition of row, the restriction electronics with incident wave (IN) ● with space zero at direct band gap A district recombination luminescence.

The application of electronic Bragg reflector of the present invention in light-emitting diode is that electronic Bragg reflector is placed between sandwich layer and the p-type covering, concrete grammar is as follows:---at concrete light-emitting diode, the energy band diagram of its structure of drawing marks the extra electric field potential energy distribution inner with it wherein; According to electric field and potential energy distribution, design its electronic Bragg reflector structure;---need limit place in the p-of electron injection type semiconductor device type side with the boundary of reflection electronic, be at first to insert the wide bandgap material of one deck 250～300A as the barrier layer between common non-doped layer and the p-type doped layer, the first acceleration layer of electronic filtering and electronics, be the artificial superlattice electronic Bragg reflector that forms by two kinds of semi-conducting material alternating layers then, the semi-conducting material of artificial superlattice layer that constitutes this electronic Bragg reflector is to the refractive index difference of electronics, and make its refringence big as far as possible, suitable 1/4th electron wavelength equivalent thicknesss of thickness of layer, equivalent thickness is defined as actual geometric thickness and its product to the electronics refractive index;

With design gallium aluminium indium phosphate material growing system is example.Select gallium arsenide substrate for use during the material growth, adopt the epitaxial growth of lattice match, get Al _0.51In _0.49P is a high refractive index layer, (Ga _1-YAl _Y) _0.51In _0.49P is a low-index layer.

Epitaxial loayer and GaAs lattice match.

Calculate electronics with the lattice constant of GaAs and equal to occur on the 5.6532A energy that the electron institute of Bragg reflection should have in lattice constant, the accelerating voltage that electronics must have is decided to be 1.7385eV.

This accelerating voltage is divided into 10 ladders calculates corresponding electronics de Broglie wave wavelength in a vacuum.Getting λ i (i=1,3,5,7,9) is mean wavelength, calculates the physical thickness of λ i/4.---according to the potential field of each layer and the energy of electronics, calculate the electronics refractive index of equivalent layer;

For example can band and component relation for gallium aluminium indium phosphorus series material, can draw curve as shown in Figure 2 by the empirical equation that experiment obtains; On the high brightness red spectral band light emitting diode construction figure (as shown in Figure 3) that U.S. EMCORE company provides, provided component; Just can carry out to be with analysis (as shown in Figure 4) according to this component; Calculate the geometric thickness of this layer according to quarter-wave light path and electronics refractive index.---the device architecture according to reality requires the thickness of the p-type limiting layer of design to distribute the actual (real) thickness of each Bragg reflecting layer;---the periodicity of high/low (1/4) λ layer of determining each Bragg reflecting layer at 6 rank of selecting or 8 rank; At concrete material growing system, consider the refractive index of material to electronics;

For example at the electronic Bragg reflector of 5890A Yellow light emitting diode design and the particular location in device architecture thereof with and band structure see Fig. 5.---according to this periodicity, the control program of design epitaxial process;---the control program of design is as a block in the existing growth procedure; This block is inserted in the former light-emitting diode growth procedure, after the active layer growth, before the growth of p-type covering.

Main points of the present invention are to have pointed out when semiconductor device is worked, electronics moves in extra electric field and the inner potential field of semiconductor, because the de Broglie wave wavelength of electronics is relevant with electronic kinetic energy, so in semiconductor device, make that electron interference forms reflection be variable period or be called the Bragg reflection structure of warbling.

The application process of electronic Bragg reflector in light-emitting diode that the present invention proposes is according to specific applied voltage and device inside band structure and Distribution of Potential Field, calculates in the electronics running variation of de Broglie wavelength and concrete numerical value thereof.

The present invention proposes and calculate in the semi-conducting material, the computational methods of corresponding specific electron wave refraction rate during the electronics operation.According to this method calculate refractive index and de Broglie wave wavelength decision realize that electronic Bragg reflects the quarter-wave geometric thickness of needed equivalence.

The effect that the ground floor potential barrier of the Bragg reflection of variable period of the present invention plays electronics filtering and just quickens.The electronics de Broglie wavelength that is accelerated reduces rapidly, and with artificial grid high-order Bragg diffraction consistent wavelength thereafter, and the natural lattice of last cycle and semi-conducting material realizes that the cycle of this wavelength high-order Bragg reflection is complementary.

In the structure of the present invention, the energy gap of electronics low-index regions and wavelength of transmitted light coupling.Be p-N-type semiconductor N material.

Design philosophy of the present invention and technology path can be used for the design of active region multi-quantum pit structure.

Electronic Bragg reflector of the present invention can be made with low pressure MOCVD technology.The present invention by the present invention, can reach nearly blue-light-emitting at design example and growth procedure that embodiment has proposed gallium aluminium indium phosphorus quaternary material with the emission wavelength blue shift 200A or 20 nanometers of this class material.

The present invention compared with prior art has following advantage:

1,, be the device architecture that can reflect the injection electronics that utilizes artificial superlattice structure to make for opto-electronic device provides a kind of new electron confinement and the structure and methods for using them of control.This structure utilize in the wave mechanics about in the principle of Bragg reflection and the quantum mechanics because the fluctuation property that the two-phase of electronics wave-particle has electronics, and according to potential energy curve in the semi-conducting material and the potential energy distribution in the semiconductor device structure, according to the wavelength and the refractive index of the de Broglie wave of particular device Structure Calculation, the distribution bragg electron reflector of design.This structure has overcome and is not enough to limit electron motion by barrier height merely so that inject the run off reduction of the device operating efficiency that causes of charge carrier, is particularly suitable for developing the short-wave long light-emitting device and other need the semiconductor device of electron confinement.

2, make us can in common MOCVD equipment, just can improve the luminous efficiency of gold-tinted easily with electronic Bragg reflector, can also develop the light-emitting diode of green glow with gallium aluminium indium phosphorus series material.We are in design and development in the process for the Bragg reflector of electronics, solved the problem of aspects such as manufacturing of application parameter, the electronic Bragg reflector of calculating, electronics refractive index, electronic Bragg reflector its specific structure, the electronic Bragg reflector of electron wavelength and device architecture coupling, we have been developed and the light-emitting diode preparing to produce has our exclusive characteristic from the beginning.

3, direct effect of the present invention is the light-emitting diodes tube efficiency raising with gallium aluminium indium phosphorus series luminescent material ripe on the present technology.At present red and orange because of barrier potential difference is bigger, efficient is than higher, and cost is lower, still, short wavelength's light more, for example yellow, green, blue aspect, luminous efficiency is very low.The present invention will reduce the leakage of injecting electronics and improve luminous efficiency, the present invention advances about 400A with these a series of luminescent materials to the shortwave direction, can develop gold-tinted (5890A), green glow (5500A), and having under the situation of stress, the light-emitting diode of the 5321A wavelength of the nearly blueness of exploitation replaces the expensive nitrogenous serial green LED of part.

4, the present invention need not to add new equipment, only changes the exploitation that the material growth structure just can be realized new product on existing MOCVD equipment.

5, the present invention is the material that the original evenly electron confinement layer (cladding layer) of component is had instead a fixed structure, when raising the efficiency, does not increase the consumption of organic source material.

6, the present invention has increased new design philosophy and method for the design of electronic device structure.

7, the present invention has provided simultaneously with turbine MOCVD equipment the grow technology and the growth procedure of this artificial superlattice electronic Bragg reflector.

Fig. 1 is an electronic Bragg reflector operation principle schematic diagram of the present invention;

Fig. 2 is that gallium aluminium indium phosphorus series material can be with the graph of a relation with component;

Fig. 3 be U.S. EMCORE company produce the double heterojunction light emitting diode structural representation;

Fig. 4 be Fig. 3 can be with analysis chart;

Fig. 5 is the 5890A Yellow light emitting diode structural representation that the electronic Bragg reflector structure is arranged.

Below by embodiment and accompanying drawing the present invention is done further narration.

Embodiment 1

As shown in Figure 2, upper curve be in aluminium indium phosphorus (AlInP) material band gap width with the variation of aluminum phosphate (AlP) content, lower curve be in gallium indium phosphorus (GaInP) material band gap width with the variation of gallium phosphide (GaP) content.Curve break is represented the variation from the direct transition band gap of high efficiency light-emitting to the very little indirect transition of luminous efficiency.

Zone with GaAs (GaAs) substrate lattice coupling in the delta-shaped region is the zone of the present invention as design example.Wherein, the highest direct band gap transmitted wave reaches 5321A, this moment material and GaAs (GaAs) substrate lattice mismatch slightly.

As shown in Figure 3, this double heterojunction light emitting diode is made of Window layer (Window layer) gallium phosphide (GAP) or gallium aluminium arsenic (AlGaAs), top covering (Upper cladding) indium gallium aluminium phosphorus (InGaAlP), under-clad layer (Lowercladding) indium gallium aluminium phosphorus (InGaAlP), sandwich layer (Active layer) indium gallium aluminium phosphorus (InGaAlP) and gallium arsenide substrate (GaAs Substrate).

As shown in Figure 4, upper and lower clad material (Upper cladding and Lower cladding) is got x=1, obtains maximum band gap width Vg=2.345eV.The loss of this layer restriction electronics.

Sandwich layer (Active layer) is got the long wavelength of y=0 for the emission of this series material, red spectral band λ=6500A, and corresponding band gap 1.9ev is expressed as solid line among the figure.Sandwich layer and covering difference in band gap reach 0.464eV, can realize operative constraint to injecting electronics.

The sandwich layer that dots among the figure is corresponding to In _0.49(Ga _0.2Al _0.8) _0.51P.The maximum direct band gap of this series material when lattice match, emission wavelength is the green glow of 5500A in theory, work do not come out but be actually.As we can see from the figure, this moment, band gap was 2.29eV, and difference in band gap is 0.055eV only, injected electronics and failed recombination luminescence and just run off, and it has been generally acknowledged that difference in band gap should be greater than 0.2eV.

Embodiment 2

As shown in Figure 5, electronic Bragg reflector places sandwich layer n-(Ga _0.52YAl _0.48) _0.51In _0.49With p-type covering p-Al _0.51In _0.49Between the P.The figure upper left is the energy band diagram that Bragg reflector amplifies, this is a variable period structure (chirpedgrating) that a material thickness by two kinds of heterogeneities successively decreases respectively, that cycle while also successively decreases, and this structure reflects the electron energy distributions that is in the electric field.Can produce this periodic structure of manually warbling with program control MOCVD technology.

Embodiment 3

Electronic Bragg reflector of the present invention is applied to the concrete enforcement of light-emitting diode can be according to the following step:---select low pressure automatic control MOCVD material growing system able to programme for use.The turbine rotary disc MOCVD material growing system of U.S. EMCORE company for example.---insert the Chirp Bragg reflector according to concrete device architecture design on the barrier layer of P/I interlayer.Method for designing adopts following forms mode of giving an example.---calculate the thickness and the component of each layer according to tabulation, every kind of component is determined growth rate in growth measured data according to this component.---determine every layer growth time according to growth rate.---according to the data and the order of tabulation, one step completed growth procedure is not interrupted in establishment.The layer of heterogeneity is to be finished by the switching of growth source material.Material has enough gaps between switching, and stops the supply of III clan source material, to guarantee accomplishing clean switching, obtains the interface of component sudden change.Growth is used for this Bragg reflector program of gold-tinted 5890A and sees design example.---the operating process of growth light-emitting diode is routinely operated the computer, and finishes the growth of the high efficiency of electronic Bragg reflector and short wavelength's luminous diode device structure material.

1, structural design for example

Example 1, gallium aluminium phosphorus indium series 5890A yellow light-emitting diode electronic Bragg reflector structure

The first step: it is as follows to list basic design parameters: emission wavelength lambda=5890A, and Bragg period thickness d (height)=d (low)=m λ/4n is got 6 rank diffraction, and m=6, n are the refractive index of this layer to electronics.The high order diffraction material is: p-Al _0.51In _0.49P, low-index material is: p-(Ga _0.52Al _0.48) _0.51In _0.49P

Second step: tabulation

Level	Ground floor	The second layer	The 3rd layer	The 4th layer	Layer 5	Layer 6
							Thickness	??L/10	??2L/10	??2L/10	??2L/10	??2L/10	??L/10
D (low) A	??51.67	??37.10	??26.72	??22.20	??19.52	??17.70
							D (height) A	??24.27	??22.15	??19.26	??17.33	??15.93	??14.86
One-period is thick	??75.94	??59.25	??45.98	??39.53	??35.45	??32.56
							Two cycles is thick	??151.88	??118.50	??91.96	??79.06	??70.90	??65.12
Three cycles are thick	??227.82	??177.75	??137.94	??118.59	??106.35	??97.68
							Phase is thick all around	??303.76	??237.00	??183.92	??158.12	??141.80	??130.24
Five cycles are thick	??379.70	??296.25	??229.90	??197.65	??177.25	??162.80
							Six cycles are thick	??455.64	??355.50	??275.88	??237.18	??212.70	??195.36
Seven cycles are thick	??531.58	??414.75	??321.86	??276.71	??248.15	??227.92
							Eight cycles are thick	??607.52	??474.00	??367.84	??316.24	??283.60	??260.48
Nine cycles are thick	??683.46	??533.25	??413.82	??355.77	??319.05	??293.04
							Ten cycles are thick	??759.40	??592.50	??459.80	??395.33	??354.50	??325.60

The 3rd step: the decision periodicity, be expressed as: a (d height+d is low), a is a periodicity.

Level	Structure	Layer geometric thickness
			Ground floor	2(51.67+33.35)	????170.04
The second layer	5(37.10+28.17)	????326.35
			The 3rd layer	6(26.72+22.60)	????295.92
The 4th layer	7(22.20+19.51)	????291.97
			Layer 5	8(19.52+17.49)	????296.08
Layer 6	5(17.70+16.04)	????168.70

Example 2, gallium aluminium phosphorus indium series 5320A blue-green light-emitting diode electronic Bragg reflector structure

The first step: it is as follows to list basic design parameters: emission wavelength lambda=5320A, and Bragg period thickness d (height)=d (low)=m λ/4n is got 10 rank diffraction, and m=10, n are the refractive index of this layer to electronics.The high order diffraction material is: p-Al _0.51In _0.49P, low-index material is: p-Al _0.44In _0.56P

Second step: tabulation

Level	Ground floor	The second layer	The 3rd layer	The 4th layer	Layer 5	Layer 6
							Thickness	????L/10	??2L/10	??2L/10	??2L/10	??2L/10	????L/10
D (low) nm	??86.12	??61.79	??44.54	??37.00	??32.54	????29.50
							D (height) nm	??76.73	??57.36	??42.16	??35.14	??30.90	????27.99
One-period is thick	??162.85	??119.15	??86.70	??72.14	??63.44	????57.49
							Two cycles is thick	??325.70	??238.30	??173.40	??144.28	??126.88	????114.98
Three cycles are thick	??488.55	??357.45	??260.10	??216.42	??190.32	????172.47
							Phase is thick all around	??651.40	??476.60	??346.80	??288.56	??253.76	????229.96
Five cycles are thick	??814.25	??595.75	??433.50	??360.70	??317.20	????287.45
							Six cycles are thick	??977.10	??714.90	??520.20	??432.84	??380.64	????344.94
Seven cycles are thick	??1139.50	??834.05	??606.90	??504.98	??444.08	????402.43
							Eight cycles are thick	??1302.80	??953.20	??693.60	??577.12	??507.52	????459.92
Nine cycles are thick	??14.65.65	??1072.35	??780.30	??649.26	??570.96	????517.41
							Ten cycles are thick	??1628.50	??1191.50	??867.00	??721.40	??634.40	????574.90

Each layer of the 3rd step decision periodicity, be expressed as: a (d height+d is low), a is a periodicity.

Level	Structure	Layer geometric thickness
			Ground floor	2(86.12+76.73)	????325.70
The second layer	5(61.79+57.36)	????595.75
			The 3rd layer	7(44.54+42.16)	????606.9
The 4th layer	9(37.00+35.14)	????649.26
			Layer 5	10(32.54+30.90)	????634.40
Layer 6	6(29.50+27.99)	????344.94

2, the method for designing of growth procedure

Be designed to example with gold-tinted: parameter of structure design is taken from the Yellow light emitting diode structural table.The growth procedure Control Parameter is taken from the data of actual measurement.Growth parameter(s) in the E204 program: rotary speed 700PPM, the pressure 25Tor of growth room, temperature=720Deg, growth rate is the 33nm/ branch, equipment time control precision one thousandth branch.List periodicity and growth time is listed as follows:

The circulation sequence number	Periodicity	High refractive index layer	Low-index layer
				????1	????1	????39.32	????117.8
Growth time	????0.118	????0.333
			????2		????2	????24.27	????68.9
Growth time	????0.073	????0.207
				????3	????5	????22.15	????49.43
Growth time	????0.066	????0.148
			????4		????7	????19.26	????35.63
Growth time	????0.058	????0.107
				????5	????8	????17.33	????29.6
Growth time	????0.052	????0.087
			????6		????9	????15.93	????26.03
Growth time	????0.048	????0.078
				????7	????5	????14.86	????23.6
Growth time	????0.045	????0.070

The insertion block of configuration is:

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R?????????R??????????R?????????R?????????R??????????R????????R?????????R?????????RHyd?inj?push??4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm

R?????????R??????????R?????????R?????????R??????????R????????R?????????R?????????RZn????????????25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm

R?????????V??????????R?????????V?????????R??????????V????????R?????????V?????????RZn?Press??????540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor

R?????????R??????????R??????????R????????R??????????R????????R?????????R?????????R

layer#????layer#????layer#????layer#????layer#????layer#????layer#????layer#????layer#

25????????26)???????7(27???????28????????29???????30)??????8(31???????32????????33

0.100min??0.066min??0.100min??0.107min??0.100min??0.058min??0.100min??0.087min??0.100minTMIn??????????420.0ccm??420.0ccm??420.0ccm??420.0ccm??420.0ccm??420.0cc???420.0cc???420.0cc???420.0cc

V??????????R?????????V??????????R????????V?????????R?????????V?????????R?????????VTMIn?Press????250.0Tor??250.0Tor??250.0Tor??250.0Tor??250.0Tor??250.0Tor??250.0Tor??250.0Tor??250.0Tor

R??????????R?????????R??????????R????????R?????????R?????????R?????????R?????????RTMGa??????????19.20ccm??19.20ccm??19.20ccm??19.20ccm??19.20ccm??19.20ccm??19.20ccm??19.20ccm??19.20ccm

V??????????R?????????V??????????V????????V?????????R?????????V?????????V?????????VTMG?Press?????950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor

R??????????R?????????R??????????R????????R?????????R?????????R?????????R?????????RTMA???????????26.0ccm???26.0ccm???101.0ccm??101.0ccm??26.0ccm???26.0ccm???101.0ccm??101.0ccm??26.0ccm

V??????????R?????????V??????????R????????V?????????R?????????V?????????R?????????VTMA?Press?????950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor

R??????????R?????????R??????????R????????R?????????R?????????R?????????R?????????RPH3???????????1700ccm???1700ccm???1700ccm???1700ccm???1700ccm???1700ccm???1700ccm???1700ccm???1700ccm

R??????????R?????????R??????????R????????R?????????R?????????R?????????R?????????RAlk?inj?push??4000ccm????4000ccm??4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm

R??????????R?????????R??????????R????????R?????????R?????????R?????????R?????????RHyd?inj?push??4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm

R??????????R?????????R??????????R?????????R????????R?????????R?????????R?????????RZn????????????25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm

V??????????R?????????V??????????R?????????V????????R??????????V????????R?????????VZn?Press??????540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor

R??????????R?????????R??????????R?????????R????????R??????????R????????R?????????R

layer#????layer#????layer#????layer#????layer#????layer#????layer#????layer#????layer#

34)??????9(35???????36?????????37????????38)??????5(39??????40????????41????????42)

0.052min??0.100min??0.078min??0.100min??0.048min??0.100min??0.070min??0.100min??0.045minTMIn??????????420.0cc???420.0cc???420.0cc???420.0cc???420.0cc???420.0cc???420.0cc???420.0cc???420.0cc

R?????????V?????????R?????????V?????????R?????????V?????????R?????????V?????????RTMInPress?????250.0Tor??250.0Tor??250.0Tor??250.0Tor??250.0Tor??250.0Tor??250.0Tor??250.0Tor??250.0Tor

R?????????R?????????R?????????R?????????R?????????R?????????R?????????R?????????RTMGa??????????19.20ccm??19.20ccm??19.20ccm??19.20ccm??19.20ccm??19.20ccm??19.20ccm??19.20ccm??19.20ccm

R?????????V?????????V?????????V?????????R?????????V?????????V?????????V?????????RTMG?Press?????950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor

R?????????R?????????R?????????R?????????R?????????R?????????R?????????R?????????RTMA???????????26.0ccm???101.0ccm??101.0ccm??26.0ccm???26.0ccm???101.0ccm??101.0ccm??26.0ccm???26.0ccm

R?????????V?????????R?????????V?????????R?????????V?????????R?????????V?????????RTMA?Press?????950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor??950.0Tor

R?????????R?????????R?????????R?????????R?????????R?????????R?????????R?????????RPH3???????????1700ccm???1700ccm???1700ccm???1700ccm???1700ccm???1700ccm???1700ccm???1700ccm???1700ccm

R?????????R?????????R?????????R?????????R?????????R?????????R?????????R?????????RAlk?inj?push??4000ccm???4000ccn???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm

R?????????R?????????R?????????R?????????R?????????R?????????R?????????R?????????RHyd?inj?push??4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm???4000ccm

R?????????R?????????R?????????R?????????R?????????R?????????R?????????R?????????RZn????????????25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm??25.00ccm

R?????????V?????????R?????????V?????????R?????????V?????????R?????????V?????????RZn?Press??????540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor??540.0Tor

R?????????R?????????R?????????R?????????R?????????R?????????R?????????R?????????R

Claims (2)

1, a kind of electronic Bragg reflector is characterized in that forming by the semiconductor material layer of two kinds of heterogeneities is alternately folded mutually, and the thickness of material successively decreases respectively, and the varied in thickness cycle successively decreases by the periodic law of manually warbling simultaneously.

2, the application of a kind of electronic Bragg reflector in light-emitting diode, it is characterized in that electronic Bragg reflector is placed between sandwich layer and the p-type covering, concrete grammar is as follows:---at concrete light-emitting diode, the energy band diagram of its structure of drawing marks the extra electric field potential energy distribution inner with it wherein; According to electric field and potential energy distribution, design its electronic Bragg reflector structure;---need limit place in the p-of electron injection type semiconductor device type side with the boundary of reflection electronic, be at first to insert the first acceleration layer of the wide bandgap material of one deck 250～300A between common non-doped layer and the p-type doped layer as barrier layer, electronic filtering and electronics, be the artificial superlattice electronic Bragg reflector that forms by two kinds of semi-conducting material alternating layers then, the semi-conducting material of artificial superlattice layer that constitutes this electronic Bragg reflector is to the refractive index difference of electronics, suitable 1/4th electron wavelength equivalent thicknesss of thickness of layer;---according to the potential field of each layer and the energy of electronics, calculate the electronics refractive index of equivalent layer;---the device architecture according to reality requires the thickness of the p-type limiting layer of design to distribute the actual (real) thickness of each Bragg reflecting layer;---the periodicity of high/low (1/4) λ layer of determining each Bragg reflecting layer at 6 rank of selecting or 8 rank;---according to this periodicity, the control program of design epitaxial process;---the control program of design is as a block in the existing growth procedure; This block is inserted in the former light-emitting diode growth procedure, after the active layer growth, before the growth of p-type covering.

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