[0026] See figure 1 , Is the first embodiment of the present invention, in conjunction with Figure 3 to Figure 8 As shown, the present invention provides a method for manufacturing a laser array and a multiplexer monolithic integrated chip, which includes the following steps:
[0027] Step 1: Growing n-type InP buffer layer 2, n-type AlGaInAs cladding layer 3, AlGaInAs multiple quantum well layer 4, p-type AlGaInAs cladding layer 5, InP spacer layer 6, InGaAsP grating layer 7 sequentially on n-type InP substrate 1 , InP sacrificial layer 8, forming a substrate, such as image 3 , One side of the substrate is the active area A, and the other side is the multiplexer area D, such as Figure 4. The AlGaInAs multiple quantum well layer 4 includes more than two AlGaInAs quantum wells and two upper and lower AlGaInAs refractive index graded layers. There may also be no InP spacer layer 6 in the device;
[0028] Step 2: P ions are implanted into the InP sacrificial layer 8 of the multiplexer area D and rapid thermal annealing; P ion implantation introduces a large number of point defects in the InP sacrificial layer 8, and the rapid thermal annealing moves the point defect vector quantum well layer 4 , To promote the mutual diffusion of the elements in the quantum well and the barrier to shorten the emission wavelength, so that the light can be transmitted with low loss in the multiplexer w waveguide. Since there is no ion implantation in the laser region A, the emission wavelength of the quantum well remains unchanged.
[0029] Step 3: After the InP sacrificial layer 8 is removed, a grating 9 is fabricated in the grating layer 7 of the active area A; the grating 9 is fabricated in the entire area of the active area A as Figure 4 , 5 As shown, or a part of area B of active area A, such as Image 6 , 7 Shown. The emission wavelength of the laser is λ=2neffA, where neff is the effective refractive index. By using the appropriate grating period Make Image 6 The emission wavelength of the laser in the middle B zone is greater than the emission wavelength of the multiple quantum well layer 4, and the M zone becomes a modulator zone. The quantum confinement Stark effect can be used to modulate the laser emission in the B zone. For each laser, the period of the grating 9 can be different or the same. When the grating period is the same, the width of each laser ridge waveguide is changed to achieve different emission wavelengths.
[0030] Step 4: Growing a p-type InP cladding layer 10 and a p-type InGaAs contact layer 11 on the InGaAsP grating layer 7 in the active area A and the multiplexer area D;
[0031] Step 5: Use dry etching to remove part of the p-type InGaAs contact layer 11, the p-type InP cladding layer 10, the InGaAsP grating layer 7 and the InP spacer layer 6, and form the ridge waveguides a1, a2 of each laser unit in the active area A , A3,..., an and the combiner area D form a combiner ridge waveguide W( Picture 8 ); ridge waveguide ( Picture 8 ) During the etching process, the grating layer material 7 other than the ridge waveguide is removed, so that the light has a sufficient confinement factor in the multiplexer waveguide W, which is beneficial to reduce the optical diffraction loss and reduce the size of the multiplexer. For the laser, since the grating layer 7 is on the quantum well layer 4, its etching does not affect the laser performance. Using the p-type AlGaInAs cladding layer 5 as the etching stop layer, the dry etching of the ridge waveguide automatically stops the layer at any time, and the laser and the multiplexer ridge waveguide are formed simultaneously, which simplifies the device manufacturing process. The ridge waveguides a1, a2, a3,..., an of the active area A and the multiplexer waveguide W have Picture 8 The same waveguide structure shown. The number of laser units of the laser array in area A is n, n> = 2. The multiplexer in the optical multiplexer area D is a multimode interference multiplexer or an arrayed waveguide grating multiplexer.
[0032] Step 6: Fabricate p-electrodes 12 on the ridge waveguides a1, a2, a3, ..., an of the active area A. For a device with modulator M, it is necessary to remove the upper contact layer material 11 of the isolation region C between the laser region B and the modulator region D and ion implantation for electrical isolation, such as Image 6;
[0033] Step 7: Thin the substrate 1 and fabricate the N electrode 13.
[0034] See again figure 2 , Is the second embodiment of the present invention, in conjunction with Figure 3-Figure 8 As shown, a manufacturing method of a laser array and a multiplexer monolithic integrated chip of the present invention is characterized in that it includes the following manufacturing steps:
[0035] Step 1: Growing n-type InP buffer layer 2, n-type AlGaInAs cladding layer 3, AlGaInAs multiple quantum well layer 4, p-type AlGaInAs cladding layer 5, InP spacer layer 6, InGaAsP grating layer 7 sequentially on n-type InP substrate 1 To form a substrate, such as image 3 , One side of the substrate is the active area A, and the other side is the multiplexer area D, such as Figure 4. The AlGaInAs multiple quantum well layer 4 includes more than two AlGaInAs quantum wells and two upper and lower AlGaInAs refractive index graded layers. There may also be no InP spacer layer 6 in the device;
[0036] Step 2: Make a grating 9 in the grating layer 7 of the active area A; make the grating 9 in all areas of the active area A as Figure 4 , 5 As shown, or a part of area B of active area A, such as Image 6 , 7 Shown. The emission wavelength of the laser is λ=2neffA, where neff is the effective refractive index. By using the appropriate grating period Make Image 6 The emission wavelength of the laser in the middle B zone is greater than the emission wavelength of the multiple quantum well layer 4, and the M zone becomes the modulator zone. The quantum confinement Stark effect can be used to modulate the laser emission in the B zone. For each laser, the period of the grating 9 can be different or the same. When the grating period is the same, the width of each laser ridge waveguide is changed to achieve different emission wavelengths.
[0037] Step 3: Growing a p-type InP cladding layer 10 and a p-type InGaAs contact layer 11 on the InGaAsP grating layer 7 in the active area A and the multiplexer area D;
[0038] Step 4: Sputter SiO in the device combiner area D 2 And rapid thermal annealing; using sputtered SiO 2 The diffusion of the generated point defects promotes the inter-diffusion of elements in the quantum well and the barrier, blue shifts the emission wavelength of the multiple quantum well layer 4 in the D zone, and realizes the low-loss transmission of light in the multiplexer waveguide W;
[0039] Step 5: Use dry etching to remove part of the p-type InGaAs contact layer 11, p-type InP cladding layer 10, InGaAsP grating layer 7 and InP spacer layer 6, and form the ridge waveguides a1, a2 of each laser unit in the active area A , A3,..., an and the combiner area D form the combiner ridge waveguide W( Picture 8 ); ridge waveguide ( Picture 8 ) During the etching process, the grating layer material 7 other than the ridge waveguide is removed, so that the light has a sufficient confinement factor in the multiplexer waveguide W, which is beneficial to reduce the optical diffraction loss and reduce the size of the multiplexer. For the laser, since the grating layer 7 is on the quantum well layer 4, its etching does not affect the laser performance. Using the p-type AlGaInAs cladding layer 5 as an etching stop layer, the dry etching of the ridge waveguide automatically stops the layer at any time, and the laser and the multiplexer ridge waveguide are formed at the same time, which simplifies the device manufacturing process. The ridge waveguides a1, a2, a3,..., an of the active area A and the multiplexer waveguide W have such Picture 8 The same waveguide structure shown. The number of laser units of the laser array in area A is n, n> = 2. The multiplexer of the optical multiplexer area D is a multimode interference multiplexer or an arrayed waveguide grating multiplexer.
[0040] Step 6: Fabricate p-electrodes 12 on the ridge waveguides a1, a2, a3, ..., an of the active area A. For a device with a modulator M, it is necessary to remove the upper contact layer material 11 of the isolation region C between the laser region B and the modulator region D and ion implantation for electrical isolation, such as Image 6;
[0041] Step 7: Thin the substrate 1 and fabricate the N electrode 13.
[0042] The system block diagrams and implementation circuit diagrams described above further describe the purpose, technical solutions and beneficial effects of the present invention in further detail. It should be understood that the above descriptions are only specific embodiments of the present invention and are not intended to limit the present invention. The invention, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
