CN209418985U - A tunable laser - Google Patents

Abstract

The utility model discloses a kind of tunable laser, which includes: the first substrate and the first electrode for being set to the first one side of substrate；It is set in turn in first distributed bragg reflector mirror, active layer, oxide layer, contact layer and second electrode of first substrate far from first electrode side；Second electrode is provided with overarm arm far from the side of the first substrate, attaches the permanent magnetic thin film of overarm arm setting, and attach the second distributed bragg reflector mirror of overarm arm setting；Permanent magnetic thin film is provided with planar spiral winding far from the side of the first substrate, so that the electromagnetic force between permanent magnetic thin film and the planar spiral winding for being connected with alternating current controls the deformation quantity of overarm arm.The utility model provides a kind of tunable laser, to realize a kind of response speed block, adjust the high tunable laser of frequency.

Description

A tunable laser

technical field

The utility model relates to the field of semiconductor optoelectronics, in particular to a tuneable laser.

Background technique

A vertical cavity surface emitting laser (Vertical Cavity Surface Emitting Laser, VCSEL) is a semiconductor device that can emit light perpendicular to the surface of a chip. The light extraction process needs to complete two steps of energy excitation and resonance amplification: first, the quantum wells in the active layer are excited by external energy (for example, electric energy) to generate electrons and holes, and the electrons and holes combine to emit light; Distributed Bragg reflectors are arranged on both sides of the source area, so that the light is repeatedly reflected between the two distributed Bragg reflectors to generate a resonance effect, so that the energy of the light is amplified and finally produces laser light.

Compared with traditional lasers, VCSEL has many advantages. For example, the output wavelength of VCSEL depends on the epitaxial growth of the material, and it is easy to adjust the wavelength. By controlling the length of the cavity between the upper and lower distributed Bragg reflectors, the wavelength of the laser emitted by the VCSEL can be controlled. In the prior art, VCSEL achieves wavelength adjustment through electrostatic driving. Electrostatic driving is a technology that uses the Coulomb force between charges as the driving force. For example, a distributed Bragg reflector can be placed on a deformable diaphragm Above, an electric field is formed on both sides of the diaphragm through a voltage, and the electrostatic force generated by the electric field can cause the diaphragm to deform and bend, so the distance between the distributed Bragg reflector and another distributed Bragg reflector changes, and the laser The wavelength changes, and when the voltage is removed, the electric field force disappears, and the diaphragm returns to its original state under the action of the elastic restoring force.

Utility model content

The embodiment of the utility model provides a tunable laser to realize a tunable laser in an electromagnetic driving mode, so as to improve the response speed and adjustment frequency of the tunable laser.

The embodiment of the utility model provides a tunable laser, including:

A first substrate and a first electrode disposed on one side of the first substrate; a first distributed Bragg reflector, an active layer, and a first distributed Bragg mirror disposed on a side of the first substrate away from the first electrode in sequence an oxide layer, a contact layer and a second electrode;

A cantilever arm is provided on the side of the second electrode away from the first substrate, a permanent magnetic film attached to the cantilever arm, and a second distributed Bragg reflector attached to the cantilever arm; The side of the permanent magnetic film far away from the first substrate is provided with a planar helical coil, so that the electromagnetic force between the permanent magnetic film and the planar helical coil with alternating current can affect the deformation of the cantilever arm control.

Optionally, a protective layer is provided on the side of the planar helical coil away from the first substrate for covering the planar helical coil; the protective layer is provided with a light exit hole for emitting a laser beam.

Optionally, the oxide layer is provided with a first through hole; in a direction parallel to the plane of the first substrate, the first through hole at least partially overlaps with the light exit hole.

Optionally, the second electrode is provided with a second through hole; the side of the contact layer away from the first substrate is provided with a high-permeability film, and the high-permeability film is located in the second through hole; In a direction parallel to the plane where the first substrate is located, the high permeability film covers the first through hole.

Optionally, the permanent magnetic film is disposed on the side of the cantilever arm away from the first substrate, and the permanent magnetic film is provided with a third through hole; the second distributed Bragg reflector is disposed on In the third through hole, and in a direction parallel to the plane where the first substrate is located, the second distributed Bragg reflector at least partially overlaps with the light exit hole.

Optionally, the tunable laser further includes: a first sacrificial layer and a second substrate; the first sacrificial layer is disposed between the contact layer and the cantilever arm, and is used to perform support, and form a first cavity between the cantilever arm and the second electrode; the second substrate is disposed on a side of the second distributed Bragg reflector away from the first substrate, And a second cavity is formed between the second substrate and the cantilever arm; the light exit hole extends to the second substrate and communicates with the second cavity.

Optionally, the permanent magnetic film is disposed on the side of the cantilever arm close to the first substrate, and the permanent magnetic film is provided with a fourth through hole; the second distributed Bragg reflector is disposed on In the fourth through hole, and in a direction parallel to the plane of the first substrate, the second distributed Bragg reflector at least partially overlaps with the light exit hole.

Optionally, the tunable laser further includes: a second sacrificial layer, a third sacrificial layer, and a third substrate; the second sacrificial layer is disposed between the second electrode and the cantilever arm, for controlling the The edge of the cantilever arm is supported, and a third cavity is formed between the cantilever arm and the second electrode; the third substrate is arranged on a side of the planar spiral coil close to the first substrate side; the third sacrificial layer is disposed between the third substrate and the cantilever arm, and forms a fourth cavity between the third substrate and the cantilever arm; the light exit hole extends to the third substrate and communicate with the fourth cavity.

Optionally, the tunable laser includes a planar helical coil; the light exit hole is located at the center of the planar helical coil.

Optionally, the tunable laser includes a plurality of planar helical coils; in a direction parallel to the plane where the first substrate is located, the plurality of planar helical coils are arranged symmetrically with respect to the light exit hole.

In the utility model, the tunable laser includes a first substrate, a first electrode, a first distributed Bragg reflector, an active layer, an oxide layer, a contact layer and a second electrode layer in sequence, and the first electrode and the second electrode Under the action of the voltage difference between, the active layer can be excited to emit light, and the side of the second electrode away from the first electrode is provided with a second distributed Bragg reflector, then the light is transmitted between the first distributed Bragg reflector and the Continuous reflection and strengthening between the second distributed Bragg reflector can emit laser light perpendicular to the direction of the first substrate. In addition, the second distributed Bragg reflector is attached to the cantilever arm, and the cantilever beam is provided with a permanent magnetic film. , and the permanent magnetic film is provided with a planar helical coil on the side away from the first substrate, and the planar helical coil can generate electromagnetic force on the permanent magnetic film under the action of alternating current, so that the cantilever arm is deformed, so that the second distributed Bragg The position of the reflector changes, so that the length of the resonant cavity between the first distributed Bragg reflector and the second distributed Bragg reflector changes continuously, so as to control the continuous change of the wavelength of the emitted laser light. The magnetic field changes the length of the resonant cavity, which provides a new method for realizing the wavelength tuning of the VCSEL laser. The tunable laser in this embodiment has a fast response speed, a high tuning frequency, and a simple structure.

Description of drawings

FIG. 1 is a schematic structural diagram of a VCSEL in the prior art;

Fig. 2 is a schematic structural diagram of a tunable laser provided by an embodiment of the present invention;

Fig. 3 is a top view of a tunable laser provided by an embodiment of the present invention;

Fig. 4 is a top view of another tunable laser provided by the embodiment of the present invention;

Fig. 5 is a top view of a cantilever arm provided by an embodiment of the present invention;

Fig. 6 is a schematic structural diagram of another tunable laser provided by an embodiment of the present invention;

Fig. 7 is a schematic flow chart of a manufacturing method of a tunable laser provided by an embodiment of the present invention;

Fig. 8 is a schematic flowchart of another manufacturing method of a tunable laser provided by an embodiment of the present invention;

Fig. 9 is a schematic structural diagram of a tunable laser after forming a second electrode provided by an embodiment of the present invention;

Fig. 10 is a schematic structural diagram of a tunable laser after forming a second distributed Bragg reflector provided by an embodiment of the present invention;

Fig. 11 is a schematic structural diagram of a tunable laser after forming a first cavity provided by an embodiment of the present invention;

Fig. 12 is a schematic structural diagram of a tunable laser provided by an embodiment of the present invention after forming a protective layer;

Fig. 13 is a schematic structural diagram of a tunable laser after forming a second cavity provided by an embodiment of the present invention;

Fig. 14 is a schematic flowchart of another manufacturing method of a tunable laser provided by an embodiment of the present invention;

Fig. 15 is a schematic structural diagram of another tunable laser after forming a second electrode provided by an embodiment of the present invention;

Fig. 16 is a schematic structural diagram of a tunable laser forming a stacked structure of a third sacrificial layer, a cantilever arm material layer and a second sacrificial layer provided by an embodiment of the present invention;

Fig. 17 is a schematic structural diagram of another tunable laser provided by an embodiment of the present invention after forming a protective layer;

Fig. 18 is a schematic structural diagram of another tunable laser after forming a second distributed Bragg reflector provided by an embodiment of the present invention;

Fig. 19 is a schematic structural diagram of a tunable laser after forming a fourth cavity provided by an embodiment of the present invention;

Fig. 20 is a schematic structural diagram of a tunable laser provided by an embodiment of the present invention after forming a light exit hole.

Detailed ways

Below in conjunction with accompanying drawing and embodiment the utility model is described in further detail. It can be understood that the specific embodiments described here are only used to explain the utility model, rather than limit the utility model. In addition, it should be noted that, for the convenience of description, only some structures related to the present utility model are shown in the drawings but not all structures.

The tunable laser provided in this embodiment is preferably a VCSEL, and the VCSEL is a laser that can emit light perpendicular to the surface of the chip. The typical structure of the VCSEL is shown in Figure 1, which is a schematic structural diagram of the VCSEL in the prior art, and the VCSEL is set There is an active layer 16, the active layer 16 is generally composed of quantum wells, the quantum wells can emit light under the excitation of the injection current, and the two sides of the active layer 16 are respectively provided with cladding layers 17, on both sides of the cladding layer 17 A first distributed Bragg reflector 14 and a second distributed Bragg reflector 15 are respectively provided, and each distributed Bragg reflector is produced alternately from two materials with a thickness of λ/4 with a large difference in refractive index. A distributed Bragg reflector forms a resonant cavity in the vertical direction, selects a specific frequency from the light emitted by the quantum well for reflection and superposition, and finally forms a laser of a certain frequency band. The above-mentioned structures are all arranged on the substrate 13, and the first electrode 11 is arranged on the outside of the substrate 13, and the second electrode 12 is arranged on the outside of the second distributed Bragg reflector 15. The above-mentioned first electrode 11 and the second electrode 12 It can provide injection current for the quantum well.

Compared with traditional lasers, VCSEL has many advantages. For example, the output wavelength of VCSEL depends on the epitaxial growth of the material, and it is easy to realize accurate control of the wavelength; The field emission angle is small; the vertical outgoing beam can be easily made into a two-dimensional array; on-chip testing can be carried out, which can effectively reduce the processing cost, etc.

In order to make the output wavelength of VCSEL tunable, a micro-electro-mechanical system (Micro-Electro-MechanicalSystem, MEMS) is introduced into VCSEL. MEMS-VCSEL changes the cavity length of the laser by electrostatically driving the mirror, thereby adjusting the output wavelength. MEMS-VCSEL realizes frequency sweep through electrostatic drive. The so-called electrostatic drive technology is a technology that uses the Coulomb force between charges as the driving force for driving. The electric field established by the control voltage generates an electrostatic force between the two electrode plates, and the electrode plates cause the diaphragm to deform and bend. The amount of deformation changes with the voltage, and the diaphragm drives the position of the second distributed Bragg reflector 15 to generate Variety. After the control voltage is removed, the electric field force disappears, and the diaphragm returns to the original state under the action of the elastic restoring force, so that the second distributed Bragg reflector 15 also returns to the original position.

The embodiment of the utility model provides a tunable laser, as shown in FIG. 2 , which is a schematic structural diagram of a tunable laser provided by the embodiment of the utility model. The tunable laser includes:

The first substrate 13 and the first electrode 11 arranged on one side of the first substrate 13; the first distributed Bragg reflector 14 and the active layer 16 arranged in sequence on the side of the first substrate 13 away from the first electrode 11 , an oxide layer 18, a contact layer 19 and a second electrode 12;

The side of the second electrode 12 away from the first substrate 13 is provided with a cantilever arm 20, a permanent magnetic film 21 attached to the cantilever arm 20, and a second distributed Bragg reflector 15 attached to the cantilever arm 20; A planar helical coil 22 is provided on the side of the film 21 away from the first substrate 13 , so that the electromagnetic force between the permanent magnet film 21 and the planar helical coil 22 with alternating current changes the deformation of the cantilever arm 20 .

The tunable laser provided by the embodiment of the utility model, the tunable laser sequentially includes a first substrate, a first electrode, a first distributed Bragg reflector, an active layer, an oxide layer, a contact layer and a second electrode layer. Under the action of the voltage difference between the first electrode and the second electrode, the active layer can be excited to emit light, and the side of the second electrode away from the first electrode is provided with a second distributed Bragg reflector, then the light is in the first Continuous reflection and strengthening between the distributed Bragg reflector and the second distributed Bragg reflector can emit laser light in a direction perpendicular to the first substrate. In addition, the second distributed Bragg reflector is attached to the cantilever arm, and the cantilever beam A permanent magnetic film is provided on the substrate, and the permanent magnetic film is provided with a planar helical coil on the side away from the first substrate. The planar helical coil can generate electromagnetic force on the permanent magnetic film under the action of alternating current, so that the cantilever arm is deformed. The position of the second distributed Bragg reflector is changed, so that the length of the resonant cavity between the first distributed Bragg reflector and the second distributed Bragg reflector is continuously changed to control the continuous change of the wavelength of the emitted laser light. The new embodiment changes the length of the resonant cavity by changing the magnetic field, and provides a new method for realizing the wavelength tuning of the VCSEL laser. The tunable laser in this embodiment has a fast response speed, a high adjustment frequency, and a simple structure.

The above is the core idea of the utility model, and the technical solution in the utility model embodiment will be clearly and completely described below in conjunction with the drawings in the utility model embodiment. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

Optionally, the side of the planar spiral coil 22 away from the first substrate 13 may be provided with a protective layer 23 for covering the planar spiral coil 22; the protective layer 23 is provided with a light exit hole 24 for emitting a laser beam. Metal wires connected to the planar helical coil 22 are arranged in the protective layer 23 so that the planar helical coil 22 can receive external alternating current. The protective layer 23 can protect the planar spiral coil 22 and the aforementioned metal wires. Moreover, the protective layer 23 is provided with a light exit hole 24 , so that the laser light reflected by the first DBR 14 and the second DBR 15 can exit through the light exit hole 24 . Optionally, the material of the protection layer 23 may be silicon nitride, which is a superhard substance, has lubricity and wear resistance, and is a reliable device protection material.

Optionally, refer to FIG. 3 , which is a top view of a tunable laser provided by an embodiment of the present invention. The tunable laser may comprise a planar helical coil 22 ; the light exit hole 24 is located at the center of the planar helical coil 22 . Then the planar spiral coil 22 forms an electromagnetic field uniformly arranged around the light exit hole 24 .

Optionally, as shown in FIG. 4, FIG. 4 is a top view of another tunable laser provided by an embodiment of the present invention. The tunable laser also includes a plurality of planar spiral coils 22; In the direction of the plane, if a plurality of planar helical coils 22 are arranged symmetrically with respect to the light exit hole 24, a uniform electromagnetic field can also be formed. Exemplarily, four planar helical coils 22 can be arranged, and four planar helical coils 22 surround the light exit hole 24 uniform and symmetrical settings.

Optionally, the planar spiral coil 22 can be made of high-conductivity materials such as Pt, Ti, Au, etc. The above-mentioned high-conductivity materials are the main thin film conductors, and the above-mentioned planar spiral coil 22 with relatively low thickness can be formed.

Optionally, referring to FIG. 2 , the oxide layer 18 may be provided with a first through hole 181 ; in a direction parallel to the plane of the first substrate 13 , the first through hole 181 at least partially overlaps with the light exit hole 24 . It is worth noting that the first through hole 181 is not a through hole formed by etching or the like, but an unoxidized part of the oxide layer 18, and the oxidized part of the oxide layer 18 forms a high-resistance region, which can inhibit the flow of current, so that The current is injected from the unoxidized part of the center to limit the current, so the first through hole 181 is not a through hole in the actual sense, but a current channel, and, in order to make the light emitted by the first through hole 181 The first through hole 181 is at least partially overlapped with the light exit hole 24 , and preferably, the first through hole 181 can completely overlap with the light exit hole 24 .

Optionally, the second electrode 12 may be provided with a second through hole 121; the side of the contact layer 19 away from the first substrate 13 is provided with a high-permeability film 25, and the high-permeability film 25 is located in the second through hole 121; In the direction of the plane where the first substrate 13 is located, the high permeability film 25 covers the first through hole 181 . The high-transmittance film 25 can enhance the output rate of light, and a second through hole 121 can be provided on the second electrode 12 , and the high-transparency film 25 can be provided in the second through hole 121 . In addition, the high-transparency film 25 covers the first through hole 181 so as to enhance the transmission of light emitted from the first through hole 181 .

Optionally, FIG. 5 is a top view of a cantilever arm provided by an embodiment of the present invention. Referring to FIG. 2 and FIG. The magnetic thin film 21 is provided with a third through hole 211; the second distributed Bragg reflector 15 is arranged in the third through hole 211, and in a direction parallel to the plane where the first substrate 13 is located, the second distributed Bragg reflector 15 at least partially overlaps with the light exit hole 24.

In the embodiment of the present invention, the change of the laser cavity length is driven by the electromagnetic force between the planar spiral coil 22 and the permanent magnetic film 21 . If a high-frequency current is applied to the planar spiral coil 22, a changing magnetic field will be produced in the surrounding space of the planar spiral coil 22, and the permanent magnetic film 21 positioned on the cantilever beam 20 will be subjected to force in the magnetic field, driving the cantilever beam 20 Vibrating up and down, correspondingly, the second distributed Bragg reflector 15 also vibrates up and down. The vibration of the second distributed Bragg reflector 15 causes the length of the cavity formed between the second distributed Bragg reflector 15 and the first distributed Bragg reflector 14 to change continuously, so that the wavelength of the emitted laser light changes continuously. The second distributed Bragg reflector 15 is at least partially overlapped with the light exit hole 24, so that the laser light emitted by the second distributed Bragg reflector 15 can be emitted through the light exit hole 24, preferably in a direction parallel to the plane where the first substrate 13 is located Above, the second distributed Bragg reflector 15 completely coincides with the light exit hole 24 .

Furthermore, in a direction parallel to the plane where the first substrate 13 is located, the second distributed Bragg reflector 15 , the first through hole 181 and the light exit hole 24 are completely overlapped to ensure smooth exit of the laser beam.

The permanent magnetic film 21 can be arranged at a position close to the second distributed Bragg reflector 15, and the displacement of the cantilever arm 2 at the position of the permanent magnetic film 21 is the same as that of the cantilever arm at the position of the second distributed Bragg reflector 150. 2 tends to be consistent in size. Preferably, as shown in Figure 5, the central position of the permanent magnet film 21 can be provided with a third through hole 211, and the second distributed Bragg reflector 15 is arranged in the third through hole 211, then the second distributed Bragg reflection The displacement of the cantilever arm 2 at the position of the mirror 15 is the exact displacement of the cantilever arm 2 at the position of the permanent magnetic film 21, so that the user can measure the second distributed Bragg reflection according to the current of the planar spiral coil 22. The position of the mirror 15 is precisely controlled to obtain the laser beam of the desired frequency. Moreover, the second distributed Bragg reflector 15 is located at the center of the permanent magnetic film 21, where the magnetic field is uniform, which facilitates rapid control of the laser cavity length.

Optionally, the material of the cantilever beam 20 can be a material with good mechanical properties, such as silicon nitride, silicon carbide or polysilicon, etc., all of which have high strength and plasticity, and strong impact toughness, so the cantilever beam 20 can Withstand high frequency up and down vibration without being damaged.

Optionally, the permanent magnet thin film 21 can adopt high-performance rare earth materials, such as NdFeB, SmCo, etc., so that the permanent magnet thin film 21 can maintain strong magnetism for a long time. Preferably, the high-performance rare earth material of SmCo material can be selected, and the material is Currently used permanent magnet materials with high magnetic properties.

Optionally, continuing to refer to FIG. 2, the tunable laser may also include: a first sacrificial layer 26 and a second substrate 27; the first sacrificial layer 26 is disposed between the contact layer 19 and the cantilever arm 20, for 20 for support, and form a first cavity M between the cantilever arm 20 and the second electrode 12; the second substrate 27 is arranged on the side of the second distributed Bragg reflector 15 away from the first substrate 13, A second cavity N is formed between the second substrate 27 and the cantilever arm 20 ; the light exit hole 24 extends to the second substrate 27 and communicates with the second cavity N.

The first sacrificial layer 26 is used as a supporting wall for supporting the edge of the hollowed-out cantilever arm 20, and a first cavity M is formed between the cantilever arm 20 and the second electrode 12, and a second cavity is formed between the cantilever arm 20 and the second substrate 27. cavity N, the second substrate 27 is arranged on the side of the second distributed Bragg reflector 15 and the permanent magnetic film 21 away from the first substrate 13, and the second distributed Bragg reflector 15 and the permanent magnetic film 21 are arranged on the first In the second cavity N, the upper side and the lower side of the cantilever arm 20 are cavity structures respectively, so that the cantilever arm 20 can vibrate up and down under the action of electromagnetic force. And the light exit hole 24 on the protection layer 23 extends to the second substrate 27 and communicates with the second cavity N.

Optionally, the material of the first sacrificial layer 26 can be phospho-silicate glass (phosphor silicate glass, PSG), silicon dioxide, etc., so that the first sacrificial layer 26 has high strength, and can be easily removed by etching, which is convenient for etching. The eclipse forms a supporting column or supporting wall structure.

The permanent magnetic film can be arranged on the side of the cantilever arm 20 away from the first substrate 13, as shown in Figure 2, of course, refer to Figure 6, Figure 6 is a schematic structural diagram of another tunable laser provided by the embodiment of the present invention , the permanent magnetic film 21 can also be arranged on the side of the cantilever arm 20 close to the first substrate 13, and the permanent magnetic film 21 is provided with a fourth through hole 212; the second distributed Bragg reflector 15 is arranged in the fourth through hole 212 Inside, and in a direction parallel to the plane where the first substrate 13 is located, the second distributed Bragg reflector 15 at least partially coincides with the light exit hole 24 .

The permanent magnetic film 21 is arranged on the side of the cantilever arm 20 close to the first substrate 13, and the second distributed Bragg reflector 15 is arranged in the fourth through hole 212 of the permanent magnetic film 21. Optionally, the fourth through hole The hole 212 is located at the center of the permanent magnetic film 21, so that the vibration generated by the second distributed Bragg reflector 15 is more precise, and the corresponding speed of the tunable laser is increased. Similarly, the second distributed Bragg reflector 15 is at least partially overlapped with the light exit hole 24 so as to facilitate the smooth exit of the laser beam. Preferably, in a direction parallel to the plane where the first substrate 13 is located, the second distributed Bragg reflector 15 , the first through hole 181 and the light exit hole 24 are completely overlapped.

Optionally, continuing to refer to FIG. 6, the tunable laser may further include: a second sacrificial layer 28, a third sacrificial layer 29, and a third substrate 30; the second sacrificial layer 28 is disposed between the second electrode 12 and the cantilever arm 20 space, used to support the edge of the cantilever arm 20, and form a third cavity M' between the cantilever arm 20 and the second electrode 12; the third substrate 30 is arranged on the planar spiral coil 22 close to the first substrate 13 the third sacrificial layer 29 is disposed between the third substrate 30 and the cantilever arm 20, and forms a fourth cavity N' between the third substrate 30 and the cantilever arm 20; the light exit hole 24 extends to the first The three substrates 30 communicate with the fourth cavity N'.

The second sacrificial layer 28 is arranged between the second electrode 12 and the cantilever arm 20, and forms a third cavity M' between the cantilever arm 20 and the second electrode 12, the permanent magnetic film 21 and the second distributed Bragg reflector 15 is disposed in the third cavity M', the third sacrificial layer 29 is disposed between the third substrate 30 and the cantilever arm 20, and a fourth cavity N' is formed between the third substrate 30 and the cantilever arm 20 , the upper and lower sides of the cantilever arm 20 are respectively provided with a fourth cavity N' and a third cavity M' to realize the vibration of the cantilever arm 20 . The light exit hole 24 on the protective layer 23 extends to the third substrate 30 and communicates with the fourth cavity N′.

Optionally, the material of the second sacrificial layer 28 can be phospho-silicate glass (phosphor silicate glass, PSG), silicon dioxide, etc., so that the first sacrificial layer 26 has high strength, and can be easily removed by etching, which is convenient for etching. The eclipse forms a supporting column or supporting wall structure.

Optionally, the material of the third sacrificial layer 29 may be silicon dioxide and other materials, and the third sacrificial layer 29 also has relatively high hardness, and supports the third substrate 30 .

To sum up, Fig. 2 and Fig. 6 respectively show two different structural diagrams of tunable lasers whose frequency is modulated by means of electromagnetic force adjustment, all of which can carry out second Adjustment of the position of the distributed Bragg reflector 15.

Based on the same idea, the embodiment of the present invention also provides a method for manufacturing a tunable laser, which is applicable to the tunable laser provided in any embodiment of the present invention. Fig. 7 is a schematic flowchart of a method for manufacturing a tunable laser provided by an embodiment of the present invention. As shown in Fig. 7, the method for manufacturing a tunable laser in this embodiment includes the following steps:

S101, forming a first substrate; and sequentially forming a first distributed Bragg reflector, an active layer, an oxide layer, and a contact layer on one side of the first substrate; on the first substrate away from the first distributed Bragg reflector A first electrode is formed on one side of the contact layer, and a second electrode is formed on a side of the contact layer away from the first substrate.

S102, forming a cantilever arm on the side of the second electrode far away from the first substrate, attaching the permanent magnetic film provided on the cantilever arm, and attaching the second distributed Bragg reflector provided on the cantilever arm; when the permanent magnetic film is far away from the first A planar helical coil is arranged on one side of the substrate, so that the electromagnetic force between the permanent magnetic film and the planar helical coil supplied with alternating current controls the deformation of the cantilever arm.

The manufacturing method of the tunable laser provided by the embodiment of the utility model, the tunable laser sequentially includes a first substrate, a first electrode, a first distributed Bragg reflector, an active layer, an oxide layer, a contact layer and a second electrode layer , under the action of the voltage difference between the first electrode and the second electrode, the active layer can be excited to emit light, and the side of the second electrode away from the first electrode is provided with a second distributed Bragg reflector, then the light Continuous reflection and strengthening between the first distributed Bragg reflector and the second distributed Bragg reflector can emit laser light perpendicular to the direction of the first substrate, and the second distributed Bragg reflector is attached to the cantilever arm , the cantilever beam is provided with a permanent magnetic film, and the permanent magnetic film is provided with a planar spiral coil on the side away from the first substrate, and the planar spiral coil can generate electromagnetic force on the permanent magnetic film under the action of alternating current, so that the cantilever arm Deformation causes the position of the second distributed Bragg reflector to change, so that the length of the resonant cavity between the first distributed Bragg reflector and the second distributed Bragg reflector changes continuously to control the continuous change of the wavelength of the emitted laser light , the embodiment of the utility model changes the length of the resonant cavity by changing the magnetic field, and provides a new method for realizing the wavelength tuning of the VCSEL laser. The tunable laser in this embodiment has a fast response speed, a high adjustment frequency, and a simple structure.

Optionally, the oxide layer may be provided with a first through hole; after forming the second electrode on the side of the contact layer away from the first substrate, it further includes: forming a second through hole by etching on the second electrode, and A high-permeability film is arranged at the second through-hole; in a direction parallel to the plane where the first substrate is located, the high-permeability film covers the first through-hole.

On the basis of the above embodiments, the cantilever arm is formed on the side of the second electrode away from the first substrate, the permanent magnetic film attached to the cantilever arm is attached, and the second distributed Bragg reflector is attached to the cantilever arm. The specific process is described in detail, referring to Fig. 8, Fig. 8 is a schematic flow chart of another method for manufacturing a tunable laser provided by an embodiment of the present invention. The method for manufacturing a tunable laser includes:

S201, forming a first substrate; and sequentially forming a first distributed Bragg reflector, an active layer, an oxide layer, and a contact layer on one side of the first substrate; on the first substrate away from the first distributed Bragg reflector A first electrode is formed on one side of the contact layer, and a second electrode is formed on a side of the contact layer away from the first substrate.

As shown in Figure 9, Figure 9 is a schematic structural diagram of a tunable laser provided by an embodiment of the present invention after the second electrode is formed, and the first substrate 13, the first distributed Bragg reflector 14, the package The cladding layer 17, the active layer 16, the cladding layer 17, the oxide layer 18 and the contact layer 19 are then deposited on the side of the first substrate 13 away from the first distributed Bragg reflector 14 to form the first electrode 11. The second electrode 12 is formed on the side of the layer 19 away from the first substrate 13. Referring to FIG. Oxidized areas, not actual vias.

S202. Etch to form a second through hole on the second electrode, and set a high-permeability film at the second through-hole; in a direction parallel to the plane where the first substrate is located, the high-permeability film covers the first substrate formed by the oxide layer. through hole.

Continuing to refer to FIG. 9 , the second through hole 121 is formed by etching on the second electrode 12 , and the high permeability film 25 is formed in the second through hole 121 , and the high permeability film 25 can cover the first through hole 181 provided by the oxide layer 18 . It should be noted that the edge portion of the second electrode 12 is also etched away to expose the contact layer 19 so as to provide the first sacrificial layer on the contact layer 19 .

S203, depositing a first sacrificial layer in a direction in which the second electrode and the high-permeability film are away from the first substrate.

S204. Deposit a cantilever beam material layer on the first sacrificial layer.

S205 , forming a permanent magnetic thin film on the cantilever beam material layer, and etching the permanent magnetic thin film to form a third through hole.

S206, setting a second distributed Bragg reflector in the third through hole; in a direction parallel to the plane where the first substrate is located, the second distributed Bragg reflector at least partially overlaps with the first through hole.

Fig. 10 is a schematic structural diagram of a tunable laser provided by an embodiment of the present invention after forming a second distributed Bragg reflector. According to steps S203-S206, firstly, the second electrode 12 and the high-transparency film 25 are far away from the first A first sacrificial layer 26 is deposited in the direction of the substrate 13, and the first sacrificial layer 26 covers the entire first substrate 13 in a direction parallel to the first substrate 13, and is deposited on the entire first sacrificial layer 26 The cantilever beam material layer, the cantilever beam material layer is a structure that covers the first sacrificial layer 26 as a whole, and the permanent magnet film 21 is formed on the cantilever beam material layer, and the third through hole 211 is formed by etching on the permanent magnet film 21, so that The second DBR 15 can be deposited in the third through hole 211 .

Optionally, the cantilever beam material layer can be formed by chemical vapor deposition, and the permanent magnetic thin film 21 can be set by magnetron sputtering, and high-performance rare earth materials such as NdFeB and SmCo can be used.

S207, etching the cantilever beam material layer to form a cantilever beam, and etching the first sacrificial layer to form a first cavity between the cantilever beam arm and the second electrode.

Fig. 11 is a schematic structural diagram of a tunable laser provided by an embodiment of the present invention after forming a first cavity. The cantilever beam material layer is etched to form a cantilever beam 20, and the first sacrificial layer 26 is formed through the hollow structure of the cantilever beam 20. Etching is performed to form a first cavity M between the cantilever arm 20 and the second electrode 12 .

S208. Deposit a planar spiral coil on the second substrate, and form a protective layer on a side of the planar spiral coil away from the second substrate.

Fig. 12 is a schematic structural view of a tunable laser provided by an embodiment of the present invention after forming a protective layer. In addition, a second substrate 27 is obtained, and a planar spiral coil 22 is deposited on the second substrate, and the planar spiral coil 22 is provided with a power lead (not shown in FIG. 12 ), and at the same time, in order to protect the planar spiral coil 22 and the power lead, a protective layer 23 is formed on the bottom of the planar spiral coil 22 . Optionally, the planar spiral coil 22 may use high-conductivity materials such as Pt, Ti, Au, etc., and the above-mentioned high-conductivity materials are the main film conductors.

S209. Form a light exit hole by etching on the protection layer and the second substrate, and form a second cavity on a side of the second substrate away from the protection layer; the second cavity communicates with the light exit hole.

Referring to FIG. 13 , FIG. 13 is a schematic structural diagram of a tunable laser provided by an embodiment of the present invention after forming a second cavity. The protective layer 23 is etched with the light exit hole 24 and extends to part of the second substrate. 27 , and form a second cavity N on the second substrate 27 , and make the second cavity N communicate with the light exit hole 24 .

S210. Bond the second substrate to the cantilever arm; in a direction parallel to the plane where the first substrate is located, at least partially overlap the second distributed Bragg reflector with the light exit hole.

Bonding the structure in Figure 13 and the structure shown in Figure 11 to form the complete structure of the tunable laser shown in Figure 2, as shown in Figure 2, in the direction parallel to the plane where the first substrate is located, The first through hole 181 , the high-transparency film 25 , the second distributed Bragg reflector 15 and the light exit hole 24 all have overlapping areas, so as to realize the exit of the laser beam with continuously changing wavelength.

In another specific example of the embodiment of the present invention, a cantilever arm is also formed on the side of the second electrode away from the first substrate, a permanent magnetic film attached to the cantilever arm, and a second distribution of the cantilever arm is attached. The specific process of the Bragg reflector is described in detail. Referring to FIG. 14, FIG. 14 is a schematic flow chart of another method for manufacturing a tunable laser provided by an embodiment of the present invention. The method for manufacturing a tunable laser includes:

S301, forming a first substrate; and sequentially forming a first distributed Bragg reflector, an active layer, an oxide layer, and a contact layer on one side of the first substrate; A first electrode is formed on one side of the contact layer, and a second electrode is formed on a side of the contact layer away from the first substrate.

Referring to FIG. 15 , FIG. 15 is a schematic structural diagram of another tunable laser provided by an embodiment of the present invention after forming the second electrode. After forming the first substrate 13 , the first distributed Bragg reflector 14 , and the cladding in sequence, layer 17, active layer 16, cladding layer 17, oxide layer 18, and contact layer 19, after which the first electrode 11 is deposited on the side of the first substrate 13 away from the first distributed Bragg reflector 14, and the first electrode 11 is formed on the contact layer 19 forms the second electrode 12 on the side away from the first substrate 13. Referring to FIG. Oxidized areas, not actual vias.

S302. Form a second through hole by etching on the second electrode, and set a high-permeability film at the second through-hole; in a direction parallel to the plane where the first substrate is located, the high-permeability film covers the first through hole.

Continuing to refer to FIG. 15 , the second through-hole 121 is formed by etching on the second electrode 12 , and the high-permeability film 25 is formed in the second through-hole 121 , and the high-permeability film 25 can cover the first through-hole 181 provided by the oxide layer 18 . It should be noted that the edge portion of the second electrode 12 is not etched away, so that the second electrode 12 can be bonded with other structural layers.

S303, sequentially depositing and forming a third sacrificial layer, a cantilever arm material layer, and a second sacrificial layer on the third substrate.

Referring to FIG. 16, FIG. 16 is a schematic structural diagram of a tunable laser that forms a stacked structure of a third sacrificial layer, a cantilever arm material layer, and a second sacrificial layer through an embodiment of the present invention. In addition, a third substrate 30 is obtained, And depositing the third sacrificial layer 29 , the cantilever arm material layer and the second sacrificial layer 28 on the third substrate 30 in sequence.

S304. Deposit and form a planar spiral coil on a side of the third substrate away from the third sacrificial layer.

S305. Deposit a protective layer on a side of the planar spiral coil away from the third substrate.

Referring to FIG. 17, FIG. 17 is a schematic structural diagram of another tunable laser provided by an embodiment of the present invention after forming a protective layer. A planar spiral coil 22 is deposited on the side of the third substrate 20 away from the third sacrificial layer 29. , Optionally, the planar spiral coil 22 may use high-conductivity materials such as Pt, Ti, Au, etc., and the above-mentioned high-conductivity materials are the main film conductors.

And deposit protective layer 23 on the side of planar spiral coil 22 away from third substrate 30, the material of protective layer 23 can be silicon nitride, silicon nitride is a kind of superhard substance, itself has lubricity, and wear resistance , is a reliable device protection material.

S306. Etching the second sacrificial layer to form a third cavity; the third cavity is in contact with the material layer of the cantilever arm.

S307, forming a permanent magnetic thin film on a side of the cantilever arm material layer close to the third cavity; and forming a fourth through hole in the permanent magnetic thin film layer.

S308, forming a second distributed Bragg reflector in the fourth through hole.

Referring to FIG. 18, FIG. 18 is a schematic structural diagram of another tunable laser provided by an embodiment of the present invention after forming a second distributed Bragg reflector, and etching the second sacrificial layer 28 to form a third cavity M' , and then attach a cantilever beam material layer in the third cavity M' to form a permanent magnetic film 21, and form a fourth through hole 211 on the permanent magnetic film 21, and form a second distributed Bragg reflector 15 in the fourth through hole .

S309. Etching the material layer of the cantilever arm to form the cantilever beam.

S310, etching the third sacrificial layer to form a fourth cavity, where the fourth cavity is respectively in contact with the third substrate and the cantilever beam.

Referring to FIG. 19 , FIG. 19 is a schematic structural diagram of a tunable laser provided by an embodiment of the present invention after forming a fourth cavity. The cantilever arm material layer is etched to form a cantilever beam 20 , and the hollow structure of the cantilever beam 20 The third sacrificial layer 29 is etched to form a fourth cavity N', the fourth cavity N' is arranged between the third substrate 30 and the cantilever beam 20, then the third cavity M' and the fourth cavity N' The structural setting of the permanent magnet film 21 can drive the cantilever beam 20 to vibrate up and down under the action of electromagnetic force, so as to realize the change of the resonant cavity length between the first distributed Bragg reflector 14 and the second distributed Bragg reflector 15, thereby Adjust the laser wavelength.

S311. Etching the protective layer and the third substrate to form a light exit hole, the light exit hole communicates with the fourth cavity; in a direction parallel to the plane where the third substrate is located, at least part of the second distributed Bragg reflector and the light exit hole coincide.

Referring to FIG. 20, FIG. 20 is a schematic structural diagram of the tunable laser provided by the embodiment of the present invention after forming the light exit hole. The light exit hole 24 is set on the protective layer 23, and the light exit hole 24 extends into the third substrate 30. , and communicate with the fourth cavity N'.

S312 , bonding the second sacrificial layer to the second electrode; in a direction parallel to the plane where the first substrate is located, the light exit hole at least partially overlaps with the first through hole.

The tunable laser structure shown in FIG. 20 is bonded to the tunable laser structure shown in FIG. 15 , specifically, the second sacrificial layer 28 is bonded to the second electrode 12, thereby forming the Complete tunable laser structure. Optionally, in a direction parallel to the plane where the first substrate is located, the first through hole 181, the high transparency film 25, the second distributed Bragg reflector 15, and the light exit hole 24 all have overlapping regions, so as to realize continuous wavelength variation emission of the laser beam.

In the tunable laser provided in this embodiment, the change of the laser cavity length is driven by the electromagnetic force between the planar spiral coil 22 and the permanent magnetic film 21 . If a high-frequency current is applied to the planar spiral coil 22, a changing magnetic field will be produced in the surrounding space of the planar spiral coil 22, and the permanent magnetic film 21 positioned on the cantilever beam 20 will be subjected to force in the magnetic field, driving the cantilever beam 20 Vibrating up and down, correspondingly, the second distributed Bragg reflector 15 also vibrates up and down. The vibration of the second distributed Bragg reflector 15 causes the length of the cavity formed between the second distributed Bragg reflector 15 and the first distributed Bragg reflector 14 to change continuously, so that the emitted laser wavelength is constantly changed, and it is possible to The tuned laser has a fast impact speed, a simple structure, and an easy process to realize.

Note that the above are only preferred embodiments of the present invention and the applied technical principles. Those skilled in the art will understand that the utility model is not limited to the specific embodiments described here, and various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the utility model. Therefore, although the utility model has been described in detail through the above embodiments, the utility model is not limited to the above embodiments, and can also include more other equivalent embodiments without departing from the concept of the utility model. The scope of the present invention is determined by the appended claims.

Claims (10)

1. a kind of tunable laser characterized by comprising

First substrate and the first electrode for being set to first one side of substrate；First substrate is set in turn in far from institute State the first distributed bragg reflector mirror, active layer, oxide layer, contact layer and the second electrode of first electrode side；

The second electrode is provided with overarm arm far from the side of first substrate, and the permanent magnetism for attaching the overarm arm setting is thin Film, and attach the second distributed bragg reflector mirror of the overarm arm setting；The permanent magnetic thin film is far from first lining The side at bottom is provided with planar spiral winding, so that between the permanent magnetic thin film and the planar spiral winding for being connected with alternating current Electromagnetic force the deformation quantity of the overarm arm is controlled.

2. tunable laser according to claim 1, which is characterized in that

Matcoveredn is arranged far from the side of first substrate in the planar spiral winding, for covering the snail line Circle；

The protective layer is provided with light hole, is used for outgoing laser beams.

3. tunable laser according to claim 2, which is characterized in that

The oxide layer is provided with first through hole；

Where being parallel to first substrate on the direction of plane, the first through hole and the light hole are at least partly heavy It closes.

4. tunable laser according to claim 3, which is characterized in that

The second electrode is provided with the second through-hole；

The contact layer is provided with high transmittance film far from the side of first substrate, and the high transmittance film is located at second through-hole It is interior；

Where being parallel to first substrate on the direction of plane, the high transmittance film covers the first through hole.

5. tunable laser according to claim 2, which is characterized in that

The permanent magnetic thin film is set to side of the overarm arm far from first substrate, and the permanent magnetic thin film is provided with Three through-holes；

Second distributed bragg reflector mirror is set in the third through-hole, and where being parallel to first substrate On the direction of plane, second distributed bragg reflector mirror is at least partly overlapped with the light hole.

6. tunable laser according to claim 5, which is characterized in that further include: the first sacrificial layer and the second substrate；

First sacrificial layer is set between the contact layer and the overarm arm, is carried out for the edge to the overarm arm Support, and the first cavity is formed between the overarm arm and the second electrode；

Second substrate is set to side of second distributed bragg reflector mirror far from first substrate, and in institute It states and forms the second cavity between the second substrate and the overarm arm；The light hole extends to second substrate and with described The connection of two cavitys.

7. tunable laser according to claim 2, which is characterized in that

The permanent magnetic thin film is set to the overarm arm close to the side of first substrate, and the permanent magnetic thin film is provided with Four through-holes；

Second distributed bragg reflector mirror is set in the fourth hole, and where being parallel to first substrate On the direction of plane, second distributed bragg reflector mirror is at least partly overlapped with the light hole.

8. tunable laser according to claim 7, which is characterized in that further include: the second sacrificial layer, 3rd sacrifice layer With third substrate；

Second sacrificial layer is set between the second electrode and the overarm arm, for the edge to the overarm arm into Row support, and third cavity is formed between the overarm arm and the second electrode；

The third substrate is set to the planar spiral winding close to the side of first substrate；

The 3rd sacrifice layer is set between the third substrate and the overarm arm, and in the third substrate and described outstanding The 4th cavity is formed between beam arm；The light hole extends to the third substrate and is connected to the 4th cavity.

9. tunable laser according to claim 2, which is characterized in that

The tunable laser includes a planar spiral winding；The light hole is located in the planar spiral winding The heart.

10. tunable laser according to claim 2, which is characterized in that

The tunable laser includes multiple planar spiral windings；The direction of plane where being parallel to first substrate On, the multiple planar spiral winding is symmetrical arranged relative to the light hole.