CN107332620A

CN107332620A - Luminous power stable optical module and optical communication equipment

Info

Publication number: CN107332620A
Application number: CN201710342665.4A
Authority: CN
Inventors: 左瑜
Original assignee: Xian Cresun Innovation Technology Co Ltd
Current assignee: Xian Cresun Innovation Technology Co Ltd
Priority date: 2017-05-17
Filing date: 2017-05-17
Publication date: 2017-11-07

Abstract

The present invention relates to the optical module and optical communication equipment that a kind of luminous power is stable, the optical module includes：Infrared LED (10), for generating infrared light in the presence of driving current；Light sensing circuit (11), electrically connects the infrared LED (10), the luminous power for measuring the infrared LED (10), and generate the photoelectric current matched with the luminous power；Feedback regulating circuit (12), electrically connect the infrared LED (10) and the light sensing circuit (11), for receiving after the photoelectric current through the processing generation driving current, driving current inverse change with the change of the photoelectric current.The optical module and optical communication equipment that the present invention is provided can realize that the luminous efficiency of infrared light is stable.

Description

Optical module with stable luminous power and optical communication equipment

Technical Field

The invention belongs to the technical field of optical fiber communication, and particularly relates to an optical module with stable luminous power and optical communication equipment.

Background

An optical module (transmissive module) is widely applied to various optical communication devices and comprises an optoelectronic device, a functional circuit, an optical interface and the like, wherein the optoelectronic device comprises a transmitting part and a receiving part. The transmit part is typically: the electric signal with a certain code rate is processed by an internal driving chip to drive a semiconductor Laser (LD) or a Light Emitting Diode (LED) to emit a modulated optical signal with a corresponding rate. The receiving part is typically: the optical signal with a certain code rate is input into the module and then converted into an electric signal by the optical detection diode. After passing through the preamplifier, the electric signal with corresponding code rate is output. In brief, the optical module functions as a photoelectric converter, the transmitting end converts an electrical signal into an optical signal, and the receiving end converts the optical signal into the electrical signal after the optical signal is transmitted through the optical fiber.

Due to the characteristics of the semiconductor laser, when the temperature is high, the light emitting power of the semiconductor laser changes, and particularly at high temperature, the light emitting efficiency of the optical module is rapidly reduced, and the light transmission performance of the optical module is affected.

Disclosure of Invention

In order to solve the above technical problem, the present invention provides an optical module and an optical communication device with stable light emitting power.

An embodiment of the present invention provides an optical module with stable light emitting power, including:

an infrared LED (10) for generating infrared light under the action of a drive current;

the light sensing circuit (11) is electrically connected with the infrared LED (10) and is used for measuring the luminous power of the infrared LED (10) and generating photocurrent matched with the luminous power;

and the feedback adjusting circuit (12) is electrically connected with the infrared LED (10) and the light sensing circuit (11) and is used for receiving the photocurrent, processing the photocurrent and generating the driving current so as to adjust the light emission of the infrared LED (10).

In one embodiment provided by the present invention, the optical module further includes:

a temperature sensor (20) for monitoring a first temperature of a processor (30) of the light module;

a processor (30) electrically connected to the temperature sensor (20) for determining a second temperature based on the first temperature to cause the feedback conditioning circuit (12) to generate the drive current based on the second temperature.

In one embodiment provided by the present invention, the light module further comprises a memory (40), and the memory (40) is electrically connected to the processor (30) for storing a first matching table, wherein the first matching table indicates a matching relationship between the first temperature and the second temperature.

In one embodiment of the present invention, the memory (40) is further configured to store a second matching table indicating a matching relationship of the second temperature with the driving circuit.

In one embodiment provided by the invention, the infrared LED (10) comprises an LED chip (1001), a substrate (1002), a lens (1003), a gold wire (1004) and a resin material (1005); wherein,

the LED chip (1001) is located at a middle groove portion of the substrate (1002);

two ends of the gold wire (1004) are respectively connected with the metal wire on the substrate (1002) and the LED chip (1001);

the lens (1003) is positioned on the substrate (1002) and fixedly connected with the substrate (1002);

the resin material (1005) is located in a cavity formed by the substrate (1002) and the lens (1003).

In one embodiment of the invention, the infrared LED (10) has a light emission wavelength of 1550nm to 1650 nm.

In one embodiment provided by the present invention, the LED device of the LED chip (1001) comprises: the semiconductor device comprises a substrate (101), a P-type crystallized Ge layer (102), an intrinsic Ge layer (103), an N-type Ge layer (104) and a passivation layer (105);

wherein the P-type crystallized Ge layer (102), the intrinsic Ge layer (103), the N-type Ge layer (104) and the passivation layer (105) are sequentially laminated on the substrate (101).

In one embodiment provided by the invention, the LED device further comprises a positive electrode (106) and a negative electrode (107), wherein the positive electrode (106) and the negative electrode (107) are respectively connected with the P-type crystallized Ge layer (102) and the N-type Ge layer (104).

In one embodiment provided by the present invention, the positive electrode (106) and the negative electrode (107) are both Cr-Au alloy materials.

An embodiment of the present invention further provides an optical communication device, including the optical module mentioned in any of the above embodiments.

According to the optical module and the optical communication equipment provided by the invention, the infrared LED replaces a semiconductor laser to emit light, and an optical sensing feedback mode is adopted, so that the working power stability of the optical module is ensured, and the influence of the external temperature change on the optical module during optical communication is reduced.

Drawings

The following detailed description of embodiments of the invention will be made with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram of an optical module with stable light emitting power according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a feedback regulation circuit according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of another optical module with stable light emitting power according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of an infrared LED according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of an LED device according to an embodiment of the present invention;

6 a-6 m are schematic diagrams of a method for fabricating an LED device according to an embodiment of the present invention;

fig. 7 is a schematic diagram of an LRC process according to an embodiment of the invention.

Detailed Description

The present invention will be described in further detail with reference to specific examples, but the embodiments of the present invention are not limited thereto.

Example one

Referring to fig. 1, fig. 1 is a schematic structural diagram of an optical module with stable light emitting power according to an embodiment of the present invention, where the optical module includes:

and the feedback adjusting circuit (12) is electrically connected with the infrared LED (10) and the light sensing circuit (11) and is used for receiving the photocurrent, processing the photocurrent and generating the driving current so as to adjust the light emission of the infrared LED (10). Wherein the driving current varies inversely with a variation of the photocurrent.

In this embodiment, the light sensing circuit (11) may comprise a light sensor for measuring the light emitting power of the infrared LED (10), the light sensor converting the measured light emitting power of the infrared LED (10) into a photocurrent, and the photocurrent is used for monitoring the light emitting state of the infrared LED (10). When the light sensor senses that the luminous power of the infrared LED (10) is reduced, the generated photocurrent is reduced; conversely, the photocurrent will increase.

In this embodiment, the feedback adjusting circuit (12) may output a larger driving current when the received light current thereof is small (at this time, the driving current of the infrared LED tends to be small), and output a smaller driving current when the received light current thereof is large (at this time, the driving current of the infrared LED tends to be large), so that the light emitting power of the optical module is stable.

Referring to fig. 2, fig. 2 is a schematic diagram of a feedback regulation circuit according to an embodiment of the present invention. Of course, the feedback regulating circuit (12) provided in this embodiment can be various automatic power control circuits mature in the prior art, i.e. APC circuits, and the invention is not limited herein.

Further, on the basis of the above embodiments, please refer to fig. 3, and fig. 3 is a schematic structural diagram of another optical module with stable light emitting power according to an embodiment of the present invention. Optionally, the optical module provided in the embodiment of the present invention further includes:

Further, on the basis of the above embodiment, the temperature control device further comprises a memory (40), wherein the memory (40) is electrically connected to the processor (30) and is used for storing a first matching table, and the first matching table indicates the matching relationship between the first temperature and the second temperature.

Further, in another embodiment provided by the present invention, the memory (40) is further configured to store a second matching table indicating a matching relationship of the second temperature with the driving circuit.

The control method can be used for directly and quickly controlling the magnitude of the driving current according to the temperature of the optical module under the conditions that the feedback adjusting circuit is not adjusted timely or fails when the optical module works at a high temperature or the temperature changes violently. The first temperature of the embodiment is an internal temperature of the optical module, and the second temperature is an external ambient temperature of the optical module. The processor, for example, may be a micro processing unit MCU, and may obtain the external environment temperature of the optical module according to the internal temperature of the optical module (the internal temperature and the external environment temperature may be obtained through a test in advance).

According to the optimal matching relation between the external environment temperature and the driving current of the infrared LED (10), wherein the matching relation can be obtained through experiments in advance, the driving current matched with the external environment temperature is generated for stably driving the infrared LED (10). In this embodiment, the driving current generating device is connected to the processor, and after receiving the command for generating the driving current, the command can be executed more quickly and accurately. The driving mode of the infrared LED (10) has the advantages of being faster and more accurate.

Further, on the basis of the above embodiments, please refer to fig. 4, and fig. 4 is a schematic structural diagram of an infrared LED according to an embodiment of the present invention, where the infrared LED is used in an infrared module. The infrared LED comprises an LED chip (1001), a substrate (1002), a lens (1003), a gold wire (1004) and a resin material (1005); wherein,

Further, in the invention, the emission wavelength of the infrared LED (10) is 1550nm to 1650 nm.

Example two

Referring to fig. 5, fig. 5 is a schematic structural diagram of an LED device according to an embodiment of the present invention, where the LED device includes:

the semiconductor device comprises a substrate (101), a P-type crystallized Ge layer (102), an intrinsic Ge layer (103), an N-type Ge layer (104) and a passivation layer (105);

Further, on the basis of the above embodiment, the P-type crystallized Ge layer and the N-type crystallized Ge layer are further included, wherein the positive electrode (106) and the negative electrode (107) are respectively connected to the P-type crystallized Ge layer (102) and the N-type crystallized Ge layer (104).

Further, on the basis of the above embodiment, both the positive electrode (106) and the negative electrode (107) are made of Cr — Au alloy material.

Further, on the basis of the above embodiment, the substrate (101) is a single crystal Si material.

Further, on the basis of the above embodiment, the thickness of the P-type crystallized Ge layer (102) is 190-200 nm, and the doping concentration is 5 × 10¹⁸cm^-3。

Further, on the basis of the above embodiment, the P-type crystallized Ge layer (102) is obtained by processing the Ge epitaxial layer grown on the substrate (101) by using a laser recrystallization process, wherein the parameters of the laser recrystallization process are that the laser wavelength is 808nm, the laser spot size is 10mm × 1mm, and the laser power is 1.5kW/cm²Laser moving speed of 25mm/s。

Further, in the above embodiment, the intrinsic Ge layer (103) includes a first Ge barrier layer (1031), a GeSn layer (1032), and a second Ge barrier layer (1033), and the first Ge barrier layer (1031), the GeSn layer (1032), and the second Ge barrier layer (1033) are sequentially stacked.

Further, on the basis of the above embodiment, the thickness of the first Ge barrier layer (1031) is 12-18nm, the thickness of the GeSn layer (1032) is 150-200 nm, and the thickness of the second Ge barrier layer (1033) is 400-450 nm.

Further, on the basis of the above embodiment, the thickness of the N-type Ge layer (104) is 100-120 nm.

According to the GeSn material-based LED provided by the embodiment of the invention, GeSn is adopted to replace Ge to be used as a light source in a photoelectric integrated circuit, so that the luminous efficiency is improved, the defect expansion is effectively inhibited, and a high-quality Ge/Si virtual substrate is obtained; and moreover, a Ge barrier layer structure is introduced between the Ge doping layer and the GeSn intrinsic layer, so that the unintentional doping of the GeSn by a doping source of the Ge layer can be avoided, and the performance of the device is improved.

EXAMPLE III

Referring to fig. 6a to 6m, fig. 6a to 6m are schematic diagrams illustrating a method for manufacturing an LED device according to an embodiment of the present invention, the method includes the following steps:

s101, selecting a single crystal Si substrate 001 as shown in FIG. 6 a.

S102, growing a Ge seed layer 002 of 40-50 nm on a single crystal Si substrate 001 by using a CVD process at the temperature of 250-350 ℃, as shown in FIG. 6 b.

S103, growing a 150-250 nm Ge main body layer 003 on the surface of the Ge seed crystal layer 002 by utilizing a CVD process at the temperature of 550-600 ℃, as shown in figure 6 c.

S104, forming a Ge main body layer 0 by using a CVD processGrowing SiO with the thickness of 100-150 nm on the surface of 03₂Protective layer 004, as shown in fig. 6 d.

S105, heating the whole substrate material comprising the single crystal Si substrate 001, the Ge seed layer 002 and the Ge main body layer 003 to 700 ℃, continuously processing the whole substrate material by utilizing a laser recrystallization process to obtain a crystallized Ge layer 005, and naturally cooling the whole substrate material, wherein the laser wavelength is 808nm, the laser spot size is 10mm × 1mm, and the laser power is 1.5kW/cm²The laser moving speed was 25 mm/s.

S106, etching SiO by utilizing a dry etching process₂Protecting the layer resulting in a crystallized Ge layer 005 as shown in fig. 6 e.

S107, doping the crystallized Ge layer 005 by using an ion implantation process, wherein the doping concentration is 5 × 10¹⁸cm^-3A P-type crystallized Ge layer 006 is formed and then the entire material is annealed as shown in fig. 6 f.

S108, growing a first Ge barrier layer 007 of 12-18nm on the P-type crystallized Ge layer 006 by using a CVD process at a temperature of 300-350 ℃, as shown in FIG. 6 g.

S109 at H₂Reducing the temperature to below 350 ℃ in the atmosphere, SnCl₄And GeH₄The Ge-doped Ge barrier layer is formed by growing a 150-200 nm GeSn layer 008 on the first Ge barrier layer 007 as shown in FIG. 6h, wherein the Sn component is 8% and the Ge-doped component is 92% respectively serving as Sn and Ge sources.

S110, growing a second Ge barrier layer 009 of 400-450nm on the GeSn layer 008 at the temperature of 300-350 ℃ by using a CVD process, as shown in FIG. 6 i.

And S111, growing an N-type Ge layer 010. The temperature is reduced to below 350 deg.C, and Ge layer is grown on the second Ge barrier layer 009 by using N₂As a carrier gas, the growth rate can be increased at pH₃As a P doping source, the P doping concentration is 1 × 10¹⁹cm^-3An N-type Ge layer structure 010 of 100-120nm is formed, as shown in FIG. 6 j.

And S112, etching away the designated area comprising the first Ge barrier layer, the GeSn layer and the second Ge barrier layer by utilizing an etching process at room temperature to expose the P-type crystallized Ge layer to be used as a metal contact mesa of the P-type crystallized Ge layer, as shown in figure 6 k.

S113, growing SiO on the metal contact table top of the P-type crystallized Ge layer and the N-type Ge layer by utilizing a plasma enhanced chemical vapor deposition process₂A passivation layer 011 for isolating the mesa from external electrical contact and selectively etching SiO by etching process₂The passivation layer 011 is formed with a P-type Ge layer contact hole and an N-type Ge layer contact hole, respectively, as shown in FIG. 6 l.

S114, growing 150-200 nm Cr-Au alloy 012 serving as electrodes in the contact hole regions of the P-type Ge layer and the contact hole regions of the N-type Ge layer by using an electron beam evaporation deposition process, as shown in FIG. 6 m.

Referring to fig. 7, fig. 7 is a schematic view illustrating an LRC process according to an embodiment of the invention. The LRC process is a thermal phase transition crystallization method, the Ge epitaxial layer on the Si substrate is melted and recrystallized through laser heat treatment, dislocation defects of the Ge epitaxial layer are released transversely, the high-quality Ge epitaxial layer can be obtained, meanwhile, the LRC process can accurately control a crystallization area, the problem of mutual expansion of Si and Ge between the Si substrate and the Ge epitaxial layer in the conventional process is avoided, and the material interface characteristic between Si and Ge is good.

Example four

The embodiment of the invention also provides optical communication equipment which comprises the optical module mentioned in any embodiment as a light emitting device of the optical communication equipment.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A light module with stable luminous power is characterized by comprising:

2. The optical module of claim 1, further comprising:

3. The light module of claim 2, further comprising a memory (40), the memory (40) being electrically connected to the processor (30) for storing a first matching table indicating a matching relationship of the first temperature to the second temperature.

4. A light module as claimed in claim 3, characterized in that the memory (40) is further adapted to store a second matching table indicating a matching relationship of the second temperature to the driving circuit.

5. A light module according to claim 3, characterized in that the infrared LED (10) comprises an LED chip (1001), a substrate (1002), a lens (1003), a gold wire (1004), and a resin material (1005); wherein,

6. The optical module according to claim 5, wherein the infrared LED (10) has an emission wavelength of 1550nm to 1650 nm.

7. A light module as claimed in claim 5, characterized in that the LED device of the LED chip (1001) comprises: the semiconductor device comprises a substrate (101), a P-type crystallized Ge layer (102), an intrinsic Ge layer (103), an N-type Ge layer (104) and a passivation layer (105);

8. The light module of claim 7, characterized in that the LED device further comprises a positive electrode (106) and a negative electrode (107), the positive electrode (106) and the negative electrode (107) being connected to the P-type crystallized Ge layer (102) and the N-type Ge layer (104), respectively.

9. The light module according to claim 8, characterized in that the positive electrode (106) and the negative electrode (107) are both Cr-Au alloy material.

10. An optical communication device, characterized in that it comprises a light module according to any one of claims 1-9.