On-chip wide-spectrum wavelength-adjustable light source device and modulation method thereof

Abstract

The invention discloses an on-chip wide-spectrum wavelength-adjustable light source device and a modulation method thereof, and belongs to the field of photoelectric integration, and the on-chip wide-spectrum wavelength-adjustable light source device structurally comprises an MOS structure light-emitting device, a SiO2 layer, a Si3N4 waveguide layer, a SiO2 buffer layer and an Ag metal grating layer. According to the monolithic silicon optical integrated device based on white light, 350-950 nm continuous spectrum white light emitted by an MOS structure light-emitting device capable of being directly prepared on a Si substrate is used as the basis, a SiO2 layer, a Si3N4 waveguide layer, a SiO2 buffer layer and an Ag metal grating layer are prepared on the MOS structure light-emitting device through a COMS technology, special packaging is not needed, and the monolithic silicon optical integrated device directly works in the atmospheric environment. According to the on-chip wide-spectrum wavelength-adjustable light source device provided by the invention, a multi-wavelength spectrum output light source device with adjustable wavelength in a wide-spectrum range is realized on the same silicon substrate by utilizing a CMOS (Complementary Metal-Oxide-Semiconductor Transistor) process.

Description

Technical Field

[0001] The invention relates to the technical field of integrated circuits, and in particular to an on-chip wide spectrum wavelength tunable light source device and a modulation method thereof. Background Art

[0002] Silicon photonics integration technology integrates photonic devices and microelectronic devices on the same chip using CMOS technology, using light as the signal transmission medium to achieve on-chip optical interconnection. Compared with electrical interconnection, optical interconnection has the advantages of higher interconnection integration, larger bandwidth, lower power consumption, extremely small signal delay and crosstalk. Optoelectronics integration technology is a new research direction of modern integrated circuit technology, and this technology will lead a new revolution in integrated circuit technology.

[0003] Currently, on-chip wide spectrum wavelength modulation technology usually relies on complex external modulation equipment or uses fixed wavelength lasers with multiple filters. There are five ways to filter on-chip wide spectrum light sources: 1. Multilayer thin film filter; 2. Beam splitter or dispersion element; 3. Liquid crystal tunable filter; 4. Acousto-optic tunable filter 5. Interference filter.

[0004] However, multilayer thin-film filters can usually only be designed for a single wavelength and cannot cover a wide wavelength range; the beam splitter or dispersion element is large in size and difficult to integrate with the on-chip optical system; the liquid crystal tunable filter has a slow adjustment speed and low resolution; the acousto-optic tunable filter has difficulty in achieving narrowband filtering and the spectral resolution is not high; and the interference filter cannot flexibly adjust different wavelengths during the preparation process.

[0005] There are still the following technical problems with wide spectrum wavelength tunable light source devices: 1. Traditional on-chip wide-spectrum wavelength-tunable light source devices often rely on complex external equipment and fixed-wavelength lasers in combination with a variety of filters to achieve the required spectral selectivity, which limits the flexibility and application scope of the technology, increases the size and cost of the equipment, and complicates the overall design of the system.

[0006] 2. Existing technologies perform poorly in terms of adjustment speed and wavelength selectivity and are unable to quickly and accurately cover a wide wavelength range, limiting their effectiveness in precise spectrum management applications.

[0007] 3. Traditional modulation devices are large in size and difficult to integrate with other on-chip optical systems, which makes the design and manufacture of integrated optical systems complex and costly.

[0008] Therefore, it is particularly important to design a wide-spectrum wavelength-tunable device that can directly fabricate a filter structure on an on-chip MOS light-emitting device. Summary of the invention

[0009] The technical problem to be solved by the present invention is to provide an on-chip wide-spectrum wavelength tunable light source device and a modulation method thereof. The device has a compact structure and can realize wide-spectrum wavelength regulation, and is suitable for high-precision optical communication, spectral analysis, optical imaging and other fields.

[0010] In order to solve the above technical problems, the technical solution adopted by the present invention is: An on-chip wide spectrum wavelength tunable light source device, comprising: MOS structure light emitting device; SiO2 layer, located on the MOS structure light emitting device; Si3N4 waveguide layer, located on top of the SiO2 layer; SiO2 buffer layer, located on the Si3N4 waveguide layer; The Ag metal grating layer is located on the SiO2 buffer layer.

[0011] A further improvement of the technical solution of the present invention is that the MOS structure light-emitting device comprises a p-type doped silicon substrate, a HfO2 high-k dielectric layer and an ITO transparent top electrode in sequence.

[0012] A further improvement of the technical solution of the present invention is that the voltage applied to the MOS structure light emitting device ranges from 100mV to 60V, and the light emitting spectrum ranges from 350nm to 950nm.

[0013] A further improvement of the technical solution of the present invention is that the thickness of the SiO2 layer is 200nm.

[0014] A further improvement of the technical solution of the present invention is that the thickness of the Si3N4 waveguide layer is 100 nm.

[0015] A further improvement of the technical solution of the present invention is that the thickness of the SiO2 buffer layer is 50nm.

[0016] A further improvement of the technical solution of the present invention is that the thickness of the Ag metal grating layer is 40nm, the period is 260-605nm, and the duty cycle is 0.75.

[0017] A modulation method for an on-chip wide spectrum wavelength tunable light source device comprises the following steps: S1. A logic electrical signal is input through the control electrode to excite the MOS structure light-emitting device to emit light under an external bias voltage, thereby generating a continuous spectrum white light signal; S2, through a 200 nm thick SiO2 layer as the support layer of the dielectric waveguide, to obtain a white light signal; S3, white light signal is conducted in the 100nm thick Si3N4 waveguide layer; S4, through a 50 nm thick SiO2 buffer layer located on top of the Si3N4 waveguide layer; S5. The optical signal passes through the wide linewidth grating on the top layer; by precisely adjusting the grating period, the coupling and resonant wavelength of the optical signal can be precisely controlled to achieve selective filtering of specific wavelengths, thereby producing filtering effects of different colors.

[0018] Due to the adoption of the above technical solution, the technical progress achieved by the present invention is: 1. The present invention uses a MOS structure white light emitting device that can be directly prepared on a Si substrate as a light source, and directly prepares a dielectric waveguide composed of a three-layer structure of SiO2 / Si3N4 / SiO2 and a top Ag metal grating layer on the light emitting device. No special packaging is required, and the device works directly in an atmospheric environment. The logic electrical signal is passed through the control electrode to excite the MOS light emitting device to emit light under an external bias voltage, generating a continuous spectrum white light signal, and coupling and transmitting light through the SiO2 / Si3N4 / SiO2 three-layer structure. Then, the light source passes through the top silver grating to achieve coupling of light signals and selective filtering of specific wavelengths, thereby generating filtering effects of different wavelengths, and obtaining a light emitting device that can emit light of multiple different colors. A multi-wavelength spectrum output light source device with adjustable wavelengths in a wide spectral range is realized on the same silicon substrate.

[0019] 2. The present invention has a simple structure and is easy to integrate. It is suitable for on-chip optical systems and solves the problem that traditional on-chip wide-spectrum wavelength tunable devices are large in size and difficult to integrate. It not only improves the filtering efficiency, but also effectively reduces the manufacturing cost. The preparation process is compatible with common optoelectronic manufacturing processes and has broad application potential and market prospects.

[0020] 3. The core of the present invention is to design an on-chip wide-spectrum wavelength tunable light source device. By processing SiO2 / Si3N4 / SiO2 layers on the wide-spectrum light source light-emitting device directly prepared on a p-type Si substrate, and loading a silver grating above the SiO2 buffer layer, the device structure is simplified and the functionality and integration are improved.

[0021] 4. The present invention supports precise control of light output of different wavelengths by adjusting the period of the top silver grating layer (260nm-605nm), and can obtain filtered light with a central wavelength ranging from 350 to 950nm and a FWHM as low as 30 nm, ultimately obtaining a light-emitting device that can emit light of multiple different colors.

[0022] 5. The present invention utilizes metal gratings to regulate the propagation and filtering characteristics of light, and precisely controls the wavelength selectivity and transmission efficiency by adjusting the period and structure of the grating, which not only improves the performance of the device, but also enables optical signals to be used more effectively, thereby improving the overall photoelectric conversion efficiency.

[0023] 6. The present invention uses materials with strong chemical stability such as SiO2 and Si3N4 and adopts mature manufacturing processes, so that the device is not only reliable in performance, but also exhibits excellent stability and durability in physical and chemical environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of an on-chip wide spectrum wavelength tunable light source device provided by an embodiment of the present invention; Figure 2 A schematic diagram of a MOS structure light emitting device provided by an embodiment of the present invention; Figure 3 A light-emitting spectrum diagram of a MOS structure light-emitting device provided in an embodiment of the present invention; Figure 4 A spectrum diagram of the on-chip wide spectrum wavelength tunable light source device provided in an embodiment of the present invention emitting a central wavelength of 470nm (blue light); Figure 5 A spectrum diagram of the on-chip wide spectrum wavelength tunable light source device provided in an embodiment of the present invention emitting a central wavelength of 550nm (green light); Figure 6 A spectrum diagram of the on-chip wide spectrum wavelength tunable light source device provided in an embodiment of the present invention emitting a central wavelength of 700nm (red light); Figure 7 A flowchart of an on-chip wide spectrum wavelength tunable light source device provided by an embodiment of the present invention; Among them, 101, MOS structure light-emitting device; 102, SiO2 layer; 103, Si3N4 waveguide layer; 104, SiO2 buffer layer; 105, Ag metal grating layer; 201, P-type doped silicon substrate; 202, HfO2 high-k dielectric layer; 203, ITO transparent top electrode. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below with reference to the accompanying drawings and embodiments: In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" ... etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0026] In addition, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "several" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0027] An on-chip wide spectrum wavelength tunable light source device comprises a MOS structure light emitting device 101, a dielectric waveguide layer and an Ag metal grating layer 105 which are arranged in sequence.

[0028] The MOS structure light-emitting device 101 is directly prepared on a silicon substrate, and includes a three-layer structure of a P-type doped silicon substrate 201, a HfO2 high-k dielectric layer 202, and an ITO transparent top electrode 203. It can emit a wide spectrum of white light covering 350nm to 950nm, and is the basis for realizing optical interconnection of silicon photonic integrated devices; the dielectric layer material HfO2 in the MOS structure light-emitting device 101 can be replaced by WO2, Al2O3, TiO2 materials as the light-emitting dielectric layer to produce white light, and the transparent top electrode ITO material can be replaced by AZO, GZO materials as the transparent strip electrode material; the P-type doped silicon substrate can be replaced by an N-type doped silicon substrate.

[0029] The dielectric waveguide layer is composed of a three-layer structure of SiO2 / Si3N4 / SiO2, including a SiO2 layer 102, a Si3N4 waveguide layer 103 and a SiO2 buffer layer 104 arranged in sequence; the SiO2 layer 102 is directly prepared on the MOS structure light-emitting device 101, and has a thickness of 200 nm; the Si3N4 waveguide layer 103 is on the SiO2 layer 102, and has a thickness of 100 nm. This waveguide layer composed of a high refractive index material is a key structure for achieving efficient spectral filtering and can support light wave transmission in a specific frequency band; the SiO2 buffer layer 104 is on the Si3N4 waveguide layer 103, and has a thickness of 50 nm. The low refractive index of this material matches the glass substrate, which helps to optimize the coupling and transmission of light. The thickness adjustment of the buffer layer can be used to control the transmission bandwidth. A thin buffer layer will increase the loss of the waveguide mode, thereby widening the resonance bandwidth; The Ag metal grating layer 105 is arranged on the top layer, and includes a plurality of wide-line width Ag gratings, whose period can be adjusted from 260nm to 605nm, thickness is 40nm, and duty cycle is about 0.75. By changing the grating period, the coupling and resonant wavelength of the incident light can be precisely controlled to achieve selective filtering of specific wavelengths and filtering effects of different colors. The silver (Ag) grating layer can be replaced by other metal materials such as gold (Au), aluminum (Al) or copper (Cu).

[0030] A modulation method for an on-chip wide spectrum wavelength tunable light source device comprises the following steps: S1. A logic electrical signal is input through the control electrode to excite the MOS structure light emitting device 101 to emit light under an external bias voltage, thereby generating a continuous spectrum white light signal; S2, through a 200 nm thick SiO2 layer 102, which serves as a support layer for the dielectric waveguide, not only providing mechanical stability but also facilitating the initial coupling of optical signals; S3, the white light signal will be conducted in the 100nm thick Si3N4 waveguide layer 103; S4, through the 50 nm thick SiO2 buffer layer 104 located on the Si3N4 waveguide layer 103, the coupling and transmission of light are further optimized; S5. The optical signal passes through the wide-linewidth Ag grating on the top layer. By precisely adjusting the grating period, the coupling and resonant wavelength of the optical signal can be precisely controlled to achieve selective filtering of specific wavelengths, thereby producing filtering effects of different colors.

[0031] Example 1 like Figure 1 As shown, the on-chip wide spectrum wavelength tunable light source device includes: MOS structure light emitting device 101, used as a light source; The SiO2 layer 102 is located above the MOS structure light emitting device and is used as a supporting layer of the dielectric waveguide to provide mechanical stability and assist in the initial coupling of the optical signal; Si3N4 waveguide layer 103, located on the SiO2 layer, used to support light wave transmission in a specific frequency band; A SiO2 buffer layer 104, located on the Si3N4 waveguide layer, is used to optimize the coupling and transmission of light; The Ag metal grating layer 105 is located on the SiO2 buffer layer and is used for coupling light waves and selective filtering of specific wavelengths.

[0032] like Figure 2 As shown, the MOS structure light emitting device 101 includes: P-type doped silicon substrate 201, used as a device base and providing holes; HfO2 high-k dielectric layer 202, used as a light-emitting dielectric layer; ITO transparent top electrode 203, used as the top cathode of the MOS structure light emitting device, and reduces the loss of the device when the light passes through the thin film through its high transmittance; Figure 3 It is a light spectrum diagram of a MOS structure light emitting device. When a voltage of 100mV~60V is applied to the MOS structure light emitting device 101, it can excite 350nm~950nm continuous spectrum white light.

[0033] Figure 4 This is a spectrum diagram of the wide spectrum wavelength tunable light source device on the chip, which emits a central wavelength of 470nm (blue light) when the silver grating duty cycle is 0.75, the height is 40nm, and the period is 280nm.

[0034] Figure 5 This is a spectrum diagram of the wide spectrum wavelength tunable light source device on the chip, which emits a central wavelength of 550nm (green light) when the silver grating duty cycle is 0.75, the height is 40nm, and the period is 340nm.

[0035] Figure 6 This is a spectrum diagram of the wide spectrum wavelength tunable light source device on the chip, which emits a central wavelength of 700nm (red light) when the silver grating duty cycle is 0.75, the height is 40nm, and the period is 470nm.

[0036] The MOS structure light emitting device 101 includes a P-type doped silicon substrate 201, the doping concentration of which is 10 14 Pieces / cm 3 ~ 10 18 Pieces / cm 3 ; HfO2 high-k dielectric layer 202, with a thickness of 3nm~30nm; ITO transparent top electrode 203, with a thickness of 80nm~120nm. The thickness of the SiO2 layer 102 is 200nm. The thickness of the Si3N4 waveguide layer 103 is 100nm. The thickness of the SiO2 buffer layer 104 is 50nm. The thickness of the Ag metal grating layer 105 is 40nm, the period is 260~605nm, and the duty cycle is 0.75.

[0037] like Figure 7 As shown, a modulation method of an on-chip wide spectrum wavelength tunable light source device comprises the following steps: S1, applying voltage to the MOS structure light emitting device 101, so that it can emit continuous spectrum white light in the range of 350nm to 950nm; S2, a 200 nm thick SiO2 layer 102 directly prepared on the MOS light emitting device 101, serving as a support layer for the dielectric waveguide, providing mechanical stability and assisting in the initial coupling of the optical signal; S3, the light wave passes through the Si3N4 waveguide layer 103 with a thickness of 100nm. This high refractive index material can support the transmission of light waves in a specific frequency band; S4, the light wave passes through the 50nm thick SiO2 buffer layer 104, and the coupling and transmission of light are optimized through the low refractive index material that matches the glass substrate; S5. The final light wave passes through the Ag metal grating 105 with a top layer adjustable period of 260 nm to 605 nm, a thickness of 40 nm, and a duty cycle of about 0.75, and obtains filtered light with a central wavelength ranging from 400 to 900 nm and a FWHM as low as 30 nm.

[0038] In summary, the present invention proposes an on-chip wide spectrum wavelength tunable light source device. The present invention uses the continuous spectrum white light of 350nm~950nm emitted by the MOS structure light emitting device that can be directly prepared on the Si substrate as the basis, and prepares the SiO2 layer, waveguide layer, buffer layer, and grating layer on the MOS structure light emitting device through the COMS process. No special packaging is required, and it works directly in the atmospheric environment. The MOS light emitting device is excited to emit light under the external bias voltage by passing the logic electrical signal through the control electrode to generate a continuous spectrum white light signal. The light is coupled and transmitted through the SiO2 / Si3N4 / SiO2 three-layer structure, and then the light source passes through the silver grating on the top layer to achieve the coupling of the light signal and the selective filtering of the specific wavelength, thereby generating filtering effects of different wavelengths, and obtaining a light emitting device that can emit a variety of different colors of light. A multi-wavelength spectrum output light source device with adjustable wavelength in a wide spectrum range is realized on the same silicon substrate.

Claims

1. An on-chip wide spectrum wavelength tunable light source device, characterized in that: include: MOS structure light emitting device (101); A SiO2 layer (102) located on the MOS structure light emitting device (101); A Si3N4 waveguide layer (103) located on the SiO2 layer (102); A SiO2 buffer layer (104) is located on the Si3N4 waveguide layer (103); The Ag metal grating layer (105) is located on the SiO2 buffer layer (104).

2. The on-chip wide spectrum wavelength tunable light source device according to claim 1, characterized in that: The MOS structure light-emitting device (101) comprises in sequence a p-type doped silicon substrate, a HfO2 high-k dielectric layer (202) and an ITO transparent top electrode (203).

3. The on-chip wide spectrum wavelength tunable light source device according to claim 1, characterized in that: The MOS structure light-emitting device (101) has an applied voltage range of 100mV to 60V, and a light-emitting spectrum range of 350nm to 950nm.

4. The on-chip wide spectrum wavelength tunable light source device according to claim 1, characterized in that: The thickness of the SiO2 layer (102) is 200 nm.

5. The on-chip wide spectrum wavelength tunable light source device according to claim 1, characterized in that: The thickness of the Si3N4 waveguide layer (103) is 100 nm.

6. The on-chip wide spectrum wavelength tunable light source device according to claim 1, characterized in that: The thickness of the SiO2 buffer layer (104) is 50 nm.

7. The on-chip wide spectrum wavelength tunable light source device according to claim 1, characterized in that: The Ag metal grating layer (105) has a thickness of 40 nm, a period of 260-605 nm, and a duty cycle of 0.

75.

8. A modulation method for an on-chip wide spectrum wavelength tunable light source device, characterized in that: Using the on-chip wide spectrum wavelength tunable light source device as claimed in any one of claims 1 to 7 comprises the following steps: S1, passing a logic electrical signal through a control electrode to excite the MOS structure light emitting device (101) to emit light under an external bias voltage, thereby generating a continuous spectrum white light signal; S2, through a 200 nm thick SiO2 layer (102), as a supporting layer of the dielectric waveguide, to obtain a white light signal; S3, white light signal is conducted in the 100 nm thick Si3N4 waveguide layer (103); S4, through a 50 nm thick SiO2 buffer layer (104) located on the Si3N4 waveguide layer (103); S5. The optical signal passes through the wide linewidth grating on the top layer; by precisely adjusting the grating period, the coupling and resonant wavelength of the optical signal can be precisely controlled to achieve selective filtering of specific wavelengths, thereby producing filtering effects of different colors.

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