CN116014558A - Semiconductor modulation laser amplifier chip and preparation method thereof - Google Patents
Semiconductor modulation laser amplifier chip and preparation method thereof Download PDFInfo
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Abstract
The invention discloses a semiconductor modulation laser amplifier chip, which comprises a single-mode semiconductor laser, an electroabsorption modulator and a semiconductor optical amplifier, wherein a first electric isolation area is formed between the laser and the modulator; forming a second electrically isolated region between the modulator and the optical amplifier; the electrode of the laser is connected with an external direct current power supply through a first gold wire; the electrode of the modulator is connected with an external alternating current power supply through a second gold wire; the electrode of the optical amplifier is connected with the electrode of the laser; the laser, modulator, optical amplifier and first and second electrically isolated regions are located on the same semiconductor substrate. The invention can ensure low chirp and improve the output power of the laser in the process of long-distance high-speed optical signal transmission, and can monitor the output optical power by using backlight. The invention also discloses a preparation method of the semiconductor modulated laser amplifier chip.
Description
Technical Field
The invention relates to a chip in the field of communication, in particular to a semiconductor modulation laser amplifier chip. The invention also relates to a preparation method of the semiconductor modulation laser amplifier chip.
Background
A high-speed semiconductor laser as an optical communication signal source is a core chip for optical communication. At present, there are two types of high-speed modulation of optical signals: one is direct modulation, which directly drives a semiconductor laser to realize the output of a modulated optical signal by a high-speed electric signal; the other is external modulation, namely, the light wave continuously output by the semiconductor laser is output by an external modulator to realize high-speed modulation. External modulation requires a continuous laser and another modulator to achieve high speed modulation of the optical signal compared to a direct modulation laser. Obviously, the external modulation is more complex in structure and far more costly than the direct modulation. Direct modulation is limited by the chirp effect of the laser itself and the dispersion of the fiber, and is generally only used for transmission of high-speed optical signals over short distances. For high-speed optical signals with a C-band 10Gbit/s rate, a transmission distance of about 2 km is limited. The chirp of the external modulation signal is far lower than that of the direct modulation, and long-distance signal transmission can be realized. Thus, for long distance signal transmission, external modulation is preferred.
There are two main ways to achieve external modulation: one is to use a separate continuous laser and modulator, with the continuous light output by the laser being coupled to the modulator through an optical waveguide (typically an optical fiber). The method can fully optimize the performances of the discrete laser and the modulator to achieve the optimal optical signal transmission effect. However, the optical signal source for realizing the method has large volume and high manufacturing cost. And secondly, monolithically integrating a continuous semiconductor laser and a modulator on a semiconductor material to directly realize an integrated modulated laser light source. The method utilizes a semiconductor process, can realize mass production of high-speed modulated lasers, and has cost and volume far lower than those of external modulated lasers manufactured by a discrete method. Two types of external modulation lasers are used for integration, one type is an electroabsorption modulation laser based on the effect that the absorption of a semiconductor material changes along with the external electric field; the other is a Mach-Zehnder modulated laser based on the electro-optic effect of semiconductor materials. The former is a mainstream scheme of the integrated external modulation laser at present because of smaller volume, low modulation voltage and low manufacturing cost, and is widely used for transmitting long-distance optical signals above 40km/80km 10 Gbit/s.
The transmission of long-range optical signals is primarily limited by the chirp and power of the optical signal. The low chirp can reduce distortion of transmission of an optical signal in an optical fiber due to optical fiber dispersion; the high optical power can compensate the attenuation of the signal caused by the optical fiber loss, thereby realizing long-distance signal transmission. But for electroabsorption modulated lasers it is contradictory to achieve both low chirp and high optical power. This is because a low chirp requires that the absorption peak of the modulator be close to the wavelength of the laser, so that the modulator has a large absorption of the light output from the laser and thus reduces the output optical power of the electroabsorption modulated laser. To increase the power of the electroabsorption modulated laser, a semiconductor optical amplifier may be integrated behind the modulator. However, this method requires adding a dc driving power source and a pin on the package to drive the amplifier, and thus requires customizing components and circuits different from those of the standard components used in a large amount at present, which increases the manufacturing cost and complexity of the devices and modules. In addition, the conventional electro-absorption laser uses the backlight of the laser to monitor the output power of the laser, but when a single driving amplifier is added, the laser and the amplifier are driven by two independent current sources, and the optical power after passing through the amplifier is generated by the combined action of the laser and the amplifier, whereas the conventional backlight monitoring can only feed back and adjust the driving current of the laser, and does not adjust the driving current of the amplifier, so that the conventional backlight monitoring is not feasible any more, and the front light monitoring greatly increases the packaging cost.
The conventional electroabsorption modulated laser comprises a single-mode laser 1, a modulator 2, an electric isolation area 4 between the laser 1 and the modulator 2, a first electrode 6 connected with the laser 1, and a second electrode 7 connected with the modulator 2, as shown in fig. 1; when the electroabsorption modulated laser is packaged, the metal wire 6w is required to connect the first electrode 6 of the laser with a pin (not shown in fig. 1) of the package, so that the applied direct current DC current can drive the laser 1 to emit continuous laser light through the metal wire 6 w; the metal wire 7w connects the modulator second electrode 7 with a packaged high-speed signal line (not shown in fig. 1), so that the high-speed alternating current signal AC changes the absorption of the modulator 2 through the metal wire 7w, and realizes high-speed modulation of the continuous laser light output from the laser 1.
Due to the high absorption characteristics of the electroabsorption modulator 2 itself, typically more than half of the light from the laser 1 is lost through the modulator 2. On the other hand, the modulator 2 can introduce chirp while modulating the signal, and a large chirp will limit the transmission distance of the optical signal; while a small chirp requires that the absorption peak of the modulator 2 be as close as possible to the wavelength of the laser 1, meaning that the modulator 2 will have a greater absorption of light from the laser 1.
In order to obtain a higher output power, it is common practice to integrate a semiconductor optical amplifier after the modulator 2. The conventional electroabsorption modulated laser amplifier chip of the integrated semiconductor optical amplifier is shown in fig. 2, which is added with an optical amplifier 3 and an electrode 8 for driving the optical amplifier 3 on the basis of the electroabsorption modulated laser of fig. 1, and a second electric isolation area 5 is added between the optical amplifier 3 and the modulator 2; to drive the optical amplifier 3, another direct current power supply DC2 is applied to the optical amplifier 3 through a metal wire 8w, thereby amplifying the optical signal output from the modulator 2. Since the currents applied to the laser 1 and the optical amplifier 3 are typically different, the electro-absorption modulated laser amplifier shown in fig. 2 requires two dc power supplies to drive the laser 1 and the amplifier 3, respectively, so that the electro-absorption modulated laser with amplifier needs to add a pin on the package and one dc power supply to drive the amplifier 3 on the module circuit, thus requiring completely different package bodies, and redesigning the module circuit, increasing the package cost and circuit complexity.
Disclosure of Invention
The invention aims to solve the technical problem of providing a semiconductor modulation laser amplifier chip which can ensure low chirp and improve the output power of a laser in the process of long-distance high-speed optical signal transmission and can monitor the output optical power by using a backlight.
In order to solve the technical problems, the technical solution of the semiconductor modulation laser amplifier chip of the invention is as follows:
comprising a single-mode semiconductor laser 1, an electroabsorption modulator 2 and a semiconductor optical amplifier 3, a first electrically isolated region 4 being formed between said laser 1 and said modulator 2; a second electrically isolated region 5 is formed between the modulator 2 and the optical amplifier 3; the electrode 6 of the laser 1 is connected with an external direct current power supply DC through a first gold wire 6 w; the electrode 7 of the modulator 2 is connected with an external alternating current power supply AC through a second gold wire 7 w; the electrode 8 of the optical amplifier 3 is connected with the electrode 6 of the laser 1; the laser 1, modulator 2, optical amplifier 3 and first 4 and second 5 electrically isolated regions are located on the same semiconductor substrate.
The electrode 6 of the laser 1 of the present invention is connected to the electrode 8 of the optical amplifier 3, so that the laser 1 and the optical amplifier 3 can be connected in parallel, and the laser 1 and the optical amplifier 3 can be supplied with power by the same direct current power supply DC. The invention utilizes a single direct current power supply DC to drive the laser and the optical amplifier simultaneously, can simplify the package of the semiconductor modulation laser amplifier and the driving circuit of the module, and can realize long-distance high-speed optical signal transmission by utilizing the semiconductor modulation laser amplifier without changing the existing package and module design.
In another embodiment, the laser 1 and the optical amplifier 3 are driven in parallel by the same direct current source;
in another embodiment, the series resistance of the laser 1 and the optical amplifier 3 is inversely proportional to the operating current of the laser 1 and the optical amplifier 3.
In another embodiment, the waveguide width of the laser 1 is different from the waveguide width of the optical amplifier 3.
In another embodiment, the waveguide of the optical amplifier 3 is a tapered structure;
in another embodiment, the waveguide of the optical amplifier 3 is stepped up along the direction of light propagation.
In another embodiment, the waveguide of the optical amplifier 3 is a straight waveguide; alternatively, the waveguide of the optical amplifier 3 is a curved waveguide, so that the light-emitting surface of the optical amplifier 3 and the cavity surface of the chip form an inclined angle;
in another embodiment, the waveguide of the optical amplifier 3 is a curved waveguide, and the angle between the waveguide of the optical amplifier 3 and the normal of the light-emitting end face of the optical amplifier 3 is between 3 and 10 degrees.
In another embodiment, a resistor 9 is disposed between the first electrode 6 and the third electrode 8.
Further, the optical amplifier 3 is connected in series with the resistor 9; one end of the resistor 9 is connected with the third electrode 8 of the optical amplifier 3, and the other end of the resistor 9 is connected with the first electrode 6; the ratio of the sum of the series resistances of the resistor 9 and the optical amplifier 3 to the resistance of the laser 1 is inversely proportional to the drive currents of the optical amplifier 3 and the laser 1.
In this embodiment, the resistor 9 is connected in series with the optical amplifier 3 and then in parallel with the laser 1 and then connected to a direct current power supply DC.
Alternatively, the laser 1 is connected in series with the resistor 9; one end of the resistor 9 is connected with the laser 1, and the other end of the resistor 9 is connected with the optical amplifier 3; the ratio of the sum of the resistances of the resistor 9 and the series resistance of the laser 1 to the resistance of the optical amplifier 3 is inversely proportional to the drive currents of the optical amplifier 3 and the laser 1.
In this embodiment, the resistor 9 is connected in series with the laser 1 and then in parallel with the optical amplifier 3 and then connected to a direct current power supply DC.
In another embodiment, the laser 1 and the optical amplifier 3 are connected to the resistor 9 by gold wires, respectively.
In another embodiment, the resistor 9 is fabricated directly on the electro-absorption laser amplifier chip; alternatively, the resistor 9 is located on the substrate on which the laser amplifier chip is placed.
In another embodiment, the length of the laser 1 is between 200 and 600 micrometers;
in another embodiment, the length of the optical amplifier 3 is between 50 and 500 micrometers;
in another embodiment, the modulator 2 has a length between 50 and 300 microns;
in another embodiment, the resistance of the resistor 9 is between 0 and 15 ohms; the resistor 9 is positioned on the same semiconductor substrate; the resistor 9 is an adjustable resistor or an non-adjustable resistor with a resistance value varying between 0 and 15 ohms.
The invention also provides a preparation method of the semiconductor modulation laser amplifier chip, which adopts the technical proposal that the preparation method comprises the following steps:
the active region structures of the laser 1, the modulator 2 and the optical amplifier 3 required for growth respectively or once are grown on the semiconductor substrate by epitaxial growth;
a grating layer is manufactured above or below the active area of the laser 1;
forming an optical waveguide by etching;
the metal contact layer and the electrode are manufactured through a semiconductor process, and a first electrode 6 of the laser 1, a second electrode 7 of the modulator 2 and a third electrode 8 of the optical amplifier 3 are formed;
etching away the metal contact layers between the laser 1 and the modulator 2 and between the modulator 2 and the optical amplifier 3, and then realizing electric isolation among the laser 1, the modulator 2 and the optical amplifier 3 by etching the conductive semiconductor layer or ion implantation to form a first electric isolation region 4 and a second electric isolation region 5;
the first electrode 6 of the laser 1 is connected to the third electrode 8 of the optical amplifier 3.
The invention has the following technical effects:
the invention integrates the optical amplifier connected with the laser on the semiconductor modulation laser, increases the output optical power of the modulation laser, and makes the absorption peak of the electroabsorption modulator be as close to the working wavelength of the laser as possible, thereby reducing the chirp of the modulation optical signal, improving the semiconductor electroabsorption modulation laser and meeting the long-distance optical signal transmission. In addition, because the laser and the optical amplifier are in parallel operation, only one direct current power supply can supply current to the laser and the optical amplifier at the same time, and the working current of the laser and the optical amplifier can be distributed by adjusting the series resistance of the laser and the optical amplifier, so that two direct current power supplies are not needed to drive the laser and the optical amplifier respectively, and a standard electroabsorption laser package can be used for packaging the electroabsorption laser with the optical amplifier, thereby simplifying the packaging of the electroabsorption modulation laser. In addition, since the same direct current source is used, the drive currents of the laser and the optical amplifier can be adjusted simultaneously by the backlight monitoring, so the backlight monitoring can still be used.
The invention is compatible with the material growth and the process technology of the existing electroabsorption laser chip, and can be applicable to all semiconductor electroabsorption laser chips. In addition, the manufacturing cost of the electric absorption laser amplifier device is greatly reduced without changing the current electric absorption laser chip packaging test.
Drawings
It will be appreciated by those skilled in the art that the following description is merely illustrative of the principles of the invention, which can be applied in numerous ways to implement many different alternative embodiments. These descriptions are only intended to illustrate the general principles of the teachings of the present invention and are not meant to limit the inventive concepts disclosed herein.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the general description given above and the detailed description of the drawings given below, serve to explain the principles of the invention.
The invention is described in further detail below with reference to the attached drawings and detailed description:
FIG. 1 is a schematic diagram of a prior art electro-absorption modulated laser without an optical amplifier;
fig. 2 is a schematic diagram of another prior art separately driven semiconductor modulated laser amplifier chip;
FIG. 3 is a schematic diagram of the structure of a semiconductor modulated laser amplifier chip of the present invention;
FIG. 4 is a schematic diagram of another embodiment of the present invention with a semiconductor modulated laser amplifier chip having a tapered waveguide structure;
fig. 5 is a schematic diagram of a third embodiment of the present invention, an amplifier of the semiconductor modulated laser amplifier chip having a series resistance;
FIG. 6 is a schematic diagram of a fourth embodiment of the present invention, a laser of the semiconductor modulated laser amplifier chip having a series resistance;
fig. 7 is a schematic structural view of a fifth embodiment of the present invention, in which the resistor of the semiconductor modulated laser amplifier chip is disposed on a substrate.
The reference numerals in the drawings illustrate:
1 is a continuous single-mode laser, 2 is a modulator,
3 is a semiconductor optical amplifier, 4 is a first electrically isolated region,
and 5 is a second electrically isolated region,
6 is the electrode (i.e. the first electrode) to which the laser is connected,
7 is the electrode (i.e. the second electrode) to which the modulator is connected,
8 is an electrode (i.e. a third electrode) connected to the optical amplifier,
6w is a lead wire connected to the laser, 8w is a lead wire connected to the optical amplifier,
9 is a resistor.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. It will be apparent that the described embodiments are some, but not all, embodiments of the invention. All other embodiments, which can be made by a person skilled in the art without creative efforts, based on the described embodiments of the present invention fall within the protection scope of the present invention. Unless otherwise defined, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. The terms "first," "second," and the like, as used herein, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" and the like means that elements or items preceding the word are included in the element or item listed after the word and equivalents thereof without precluding other elements or items. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.
The core idea of the invention is that the high power output of the electroabsorption laser is obtained by driving the laser and the optical amplifier in parallel, the chirp of the output high-speed modulation signal is reduced, and meanwhile, the packaging and the driving circuit of the electroabsorption laser amplifier chip can be simplified, thereby realizing the low-cost electroabsorption modulation laser amplifier chip for long-distance transmission of the high-speed optical signal. In order to make the packaging and use of electroabsorption modulated laser amplifier chips compatible with the packaging materials and module circuits currently in heavy use, the present invention connects the electrode 6 of the laser 1 with the electrode 8 of the optical amplifier. Thus, only one direct current source is needed to drive the laser 1 and the optical amplifier 3 at the same time, so that long-distance high-speed optical signal transmission can be realized without changing the existing packaging structure and module circuit.
In order to achieve the above objective of achieving a high-power long-distance high-speed electroabsorption modulated laser amplifier based on a parallel laser and an optical amplifier, the present invention is expressed by the following embodiment that the operating wavelength is located around 1550 nm.
As shown in fig. 3, the electroabsorption modulated laser amplifier chip of the present invention comprises a laser 1, an electroabsorption modulator 2, an optical amplifier 3, a first electrically isolated region 4 between the laser 1 and the modulator 2, a second electrically isolated region 5 between the modulator 2 and the optical amplifier 3, a first electrode 6 connected to the laser 1, a second electrode 7 connected to the modulator 2, and a third electrode 8 connected to the optical amplifier 3; the first electrode 6 is connected with the third electrode 8; the first electrode 6 is connected with an external direct current power supply DC through a first gold wire 6 w; the second electrode 7 is connected to an external high-speed alternating current power source AC through a second gold wire 7 w.
All the above structures of the laser 1, modulator 2 and optical amplifier 3 are deposited on an indium phosphide substrate by epitaxial growth (typically metal organic vapor phase epitaxy MOCVD); after the crystal growth is completed, the waveguide structure is formed by an etching method. The width of the waveguide is generally about 1 to 3 microns. Etching is typically a combination of dry and wet processes. For a 1550nm electroabsorption modulated laser amplifier, the active regions of the laser 1, modulator 2 and amplifier 3 are typically indium gallium arsenide phosphide (InGaAsP) quantum well structures of different composition. The laser 1 typically comprises a grating structure because of the need for single mode operation. The laser 1 generates direct current light that enters the modulator 2 through the first electrically isolated region 4. The first and second electrically isolated regions 4, 5 may be formed by removing a surface metal layer and P-type doped semiconductor material, or by ion implantation after removing the metal layer. The isolation resistance of the first and second electrically isolated regions 4, 5 needs to be greater than five kiloohms. The absorption peak of the modulator 2 is shorter than the wavelength of the laser 1. The absorption peak of the modulator 2 moves in the long wavelength (i.e., the wavelength of the laser 1) direction with an increase in the applied reverse electric field, so that the absorption increases; the continuous light output from the laser 1 is modulated to generate a high-speed optical signal. The high-speed modulated optical signal generated by the modulator 2 passes through the second electrically isolated region 5 and enters the optical amplifier 3. The direct current source injects current into the optical amplifier 3, and generates inversion of carriers to realize amplification output of the high-speed modulated optical signal from the modulator 1.
In the present invention, since the electrode 6 of the laser 1 is connected to the electrode 8 of the optical amplifier 3, which corresponds to the common large electrode (hereinafter referred to as large electrode) for the laser 1 and the optical amplifier 3, the laser 1 and the optical amplifier 3 are connected in parallel.
Current of laser 1
Wherein V is S Is the voltage applied by the direct current power supply DC to the large electrode,
V OL is the on-voltage of the laser 1,
R LD is the series resistance of the laser 1;
current of the optical amplifier 3
Wherein V is S Is the voltage applied by the direct current power supply DC to the large electrode,
V OS is the turn-on voltage of the optical amplifier 3,
R SOA is the series resistance of the optical amplifier 3.
Since the turn-on voltages of the laser 1 and the optical amplifier 3 are almost the same, the turn-on voltages of the laser 1 and the optical amplifier 3 are almost the same
I.e. the current supplied to the laser 1 and the optical amplifier 3 by the same direct current source DC is inversely proportional to the series resistance of the laser 1 and the optical amplifier 3. The operating current (i.e. the required drive current) applied to the laser 1 and the optical amplifier 3 can be controlled by adjusting the resistance ratio of the laser 1 and the optical amplifier 3. If the current I required by the laser 1 LD Is 80mA (milliamp), current I of the optical amplifier 3 SOA The series resistance of the laser 1 was 6 ohms at 60mA, and the series resistance of the optical amplifier 3 was controlled to 8 ohms. Thus, the bias current of the laser 1 can be ensured to be 80mA and the bias current of the optical amplifier 3 can be ensured to be 60mA by only providing a bias with a total current of 140mA by the direct current power supply.
The basic structures of the laser 1 and the optical amplifier 3 are PN junction diodes, the series resistance of which is mainly determined by the ohmic contact resistance of the P-plane, and the laser 1 and the optical amplifier 3 generally have the same resistivity, so that the resistance ratio of the laser 1 and the optical amplifier 3 is mainly determined by the metal contact area of the laser 1 and the optical amplifier 3. If the waveguide widths of the laser 1 and the optical amplifier 3 are the same, the lengths of the laser 1 and the optical amplifier 3 can be adjusted to control the corresponding resistance ratios. If the laser 1 has a length of 400 μm and the corresponding series resistance is 6 ohms, the optical amplifier 3 should have a resistance of about 8 ohms, and the optical amplifier 3 should have a length of about 300 μm. Of course, the length adjustment of the optical amplifier 3 has a certain limit range because the gain of the optical amplifier 3 and the saturated optical power have a close relationship with the length. If the adjustment of the length cannot meet the required resistance requirements of the laser 1 and the optical amplifier 3, the series resistance of the optical amplifier 3 can be further modified by adjusting the waveguide width of the optical amplifier 3. For example, the waveguide of the optical amplifier 3 may be designed to have a tapered structure, and the waveguide of the optical amplifier 3 is gradually increased along the light propagation direction (as shown in fig. 4), so that the saturated optical power of the optical amplifier 3 may be increased, and the far-field divergence angle of the output light may be reduced to improve the coupling efficiency with the optical fiber.
Fig. 5 is another preferred embodiment of the present invention. If the desired series resistance ratio is still not met by adjusting the structures of the laser 1 and the optical amplifier 3, the desired resistance value can be achieved by adding a resistor. In fig. 5, a resistor 9 is added in series with the optical amplifier 3 to achieve the purpose of increasing the resistance, thereby adjusting the current injected into the laser 1 and the optical amplifier 3. Resistor 9 is typically fabricated by a semiconductor thin film process such as titanium or chromium or other metal thin films.
If the injection current of the laser 1 is required to be greater than the current of the optical amplifier 3, then the series resistance of the laser 1 is required to be greater than the series resistance of the optical amplifier 3, at which point a resistor 9 may be connected in series with the laser 1 (as in fig. 6), with a lead 6w connected to the optical amplifier 3.
The resistors in fig. 5 and 6 are fabricated directly on the electro-absorption laser amplifier chip. Of course, it may be separated from the electro-absorption laser amplifier chip and placed on the substrate where the electro-absorption laser amplifier chip is placed, as shown in fig. 7.
The electroabsorption modulated laser amplifier requires an extremely low light exit surface reflectivity to reduce the effect of reflected light on the performance of the laser 1. Therefore, the waveguide of the optical amplifier 3 can be changed from a straight waveguide to a curved waveguide, so that the light-emitting surface and the cavity surface of the chip have an inclined angle, thereby reducing the influence of reflected light caused by the reflection remaining on the cavity surface.
The preparation method of the semiconductor modulation laser amplifier chip comprises the following steps:
the active region structures of the laser 1, the modulator 2 and the optical amplifier 3 required for growth respectively or once are grown on the semiconductor substrate by epitaxial growth;
as a preferred embodiment, the laser 1, modulator 2 and optical amplifier 3 may use the same active region structure, and the active region structure is completed by one epitaxial growth;
as another preferred embodiment, the active region structure may be formed by selecting regions having slightly different growth composition and thickness;
as a third preferred embodiment, three different active region structure growth may be accomplished by optimizing the active regions of the laser 1, modulator 2 and optical amplifier 3, respectively, by multiple butt growth.
A grating layer is manufactured above or below the active region of the laser 1 to ensure that the laser 1 works in a single mode;
after the epitaxial growth is completed, forming an optical waveguide by etching to provide limitation of photon and electron injection;
then manufacturing a metal contact layer and an electrode through a semiconductor process;
the metal contact layers between the laser 1 and the modulator 2 and between the modulator 2 and the optical amplifier 3 are etched away, and then the electrical isolation between the laser 1, the modulator 2 and the optical amplifier 3 is achieved by etching the conductive semiconductor layer or ion implantation.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
Claims (12)
1. A semiconductor modulated laser amplifier chip, comprising:
a single-mode semiconductor laser (1),
an electroabsorption modulator (2),
-a first electrically isolated region (4) between the laser (1) and the modulator (2);
a first electrode (6) connected to the laser (1); the first electrode (6) is connected with an external direct current power supply (DC) through a first gold wire (6 w);
a second electrode (7) connected to the modulator (2); the second electrode (7) is connected with an external alternating current power supply (AC) through a second gold wire (7 w); and
a semiconductor optical amplifier (3),
-a second electrically isolated region (5) between the modulator (2) and the optical amplifier (3);
a third electrode (8) connected to the optical amplifier (3); the third electrode (8) is connected with the first electrode (6);
the laser (1), the modulator (2), the optical amplifier (3), the first electric isolation region (4) and the second electric isolation region (5) are positioned on the same semiconductor substrate.
2. A semiconductor modulated laser amplifier chip according to claim 1, characterized in that the laser (1) and the optical amplifier (3) are driven in parallel by the same dc current source; and/or the series resistance of the laser (1) and the optical amplifier (3) is inversely proportional to the operating current of the laser (1) and the optical amplifier (3).
3. A semiconductor modulated laser amplifier chip according to claim 1, characterized in that the waveguide width of the laser (1) is different from the waveguide width of the optical amplifier (3).
4. A semiconductor modulated laser amplifier chip according to claim 1, characterized in that the waveguide of the optical amplifier (3) is of a tapered structure; and/or the waveguide of the optical amplifier (3) is gradually increased along the light propagation direction.
5. A semiconductor modulated laser amplifier chip according to claim 1, characterized in that the waveguide of the optical amplifier (3) is a straight waveguide; or the waveguide of the optical amplifier (3) is a curved waveguide, so that the light emergent surface of the optical amplifier (3) and the cavity surface of the chip form an inclined angle; or, the waveguide of the optical amplifier (3) is a curved waveguide, and an included angle between the waveguide of the optical amplifier (3) and a normal line of an optical outlet end face of the optical amplifier (3) is between 3 and 10 degrees.
6. A semiconductor modulated laser amplifier chip according to claim 1, characterized in that a resistor (9) is arranged between the first electrode (6) and the third electrode (8).
7. A semiconductor modulated laser amplifier chip according to claim 6, characterized in that the optical amplifier (3) is connected in series with the resistor (9); one end of the resistor (9) is connected with a third electrode (8) of the optical amplifier (3), and the other end of the resistor (9) is connected with the first electrode (6); and/or the ratio of the sum of the resistances of the resistors (9) and the series resistance of the optical amplifier (3) to the resistance of the laser (1) is inversely proportional to the drive currents of the optical amplifier (3) and the laser (1).
8. The semiconductor modulated laser amplifier chip according to claim 6, characterized in that the laser (1) is connected in series with the resistor (9); one end of the resistor (9) is connected with the laser (1), and the other end of the resistor (9) is connected with the optical amplifier (3); and/or the ratio of the sum of the resistances of the resistors (9) and the series resistance of the laser (1) to the resistance of the optical amplifier (3) is inversely proportional to the drive currents of the optical amplifier (3) and the laser (1).
9. A semiconductor modulated laser amplifier chip according to claim 6, characterized in that the laser (1) and the optical amplifier (3) are connected to the resistor (9) by gold wires, respectively.
10. A semiconductor modulated laser amplifier chip according to claim 6, characterized in that the resistor (9) is fabricated directly on the electro-absorption laser amplifier chip; alternatively, the resistor (9) is located on a substrate on which the laser amplifier chip is placed.
11. The semiconductor modulated laser amplifier chip according to claim 6, characterized in that the length of the laser (1) is between 200 and 600 micrometers;
and/or the length of the optical amplifier (3) is between 50 and 500 micrometers;
and/or the modulator (2) has a length between 50 and 300 microns;
and/or the resistance of the resistor (9) is between 0 and 15 ohm; the resistors (9) are positioned on the same semiconductor substrate; the resistor (9) is an adjustable resistor or an non-adjustable resistor with the resistance value ranging from 0 to 15 ohms.
12. A method of fabricating a semiconductor modulated laser amplifier chip, comprising the steps of:
an active region structure of a laser (1), a modulator (2) and an optical amplifier (3) required for growth respectively or once by epitaxial growth on a semiconductor substrate;
a grating layer is manufactured above or below an active area of the laser (1);
forming an optical waveguide by etching;
the metal contact layer and the electrode are manufactured through a semiconductor process, and a first electrode (6) of the laser (1), a second electrode (7) of the modulator (2) and a third electrode (8) of the optical amplifier (3) are formed;
etching away metal contact layers between the laser (1) and the modulator (2) and between the modulator (2) and the optical amplifier (3), and then realizing electric isolation among the laser (1), the modulator (2) and the optical amplifier (3) by etching a conductive semiconductor layer or ion implantation to form a first electric isolation region (4) and a second electric isolation region (5);
a first electrode (6) of the laser (1) is connected to a third electrode (8) of the optical amplifier (3).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310065662.6A CN116014558A (en) | 2023-02-06 | 2023-02-06 | Semiconductor modulation laser amplifier chip and preparation method thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310065662.6A CN116014558A (en) | 2023-02-06 | 2023-02-06 | Semiconductor modulation laser amplifier chip and preparation method thereof |
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| CN116014558A true CN116014558A (en) | 2023-04-25 |
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| CN202310065662.6A Withdrawn CN116014558A (en) | 2023-02-06 | 2023-02-06 | Semiconductor modulation laser amplifier chip and preparation method thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116885560A (en) * | 2023-06-29 | 2023-10-13 | 武汉云岭光电股份有限公司 | Electroabsorption modulation laser chip and manufacturing method thereof |
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2023
- 2023-02-06 CN CN202310065662.6A patent/CN116014558A/en not_active Withdrawn
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116885560A (en) * | 2023-06-29 | 2023-10-13 | 武汉云岭光电股份有限公司 | Electroabsorption modulation laser chip and manufacturing method thereof |
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