CN212167470U

CN212167470U - Optical waveguide microfluid chip based on CMOS image sensing

Info

Publication number: CN212167470U
Application number: CN202020114726.9U
Authority: CN
Inventors: 陈昌; 刘博�; 王靖
Original assignee: Shanghai Industrial Utechnology Research Institute
Current assignee: Shanghai Jinguan Technology Co ltd
Priority date: 2020-01-17
Filing date: 2020-01-17
Publication date: 2020-12-18
Anticipated expiration: 2030-01-17

Abstract

The utility model provides an optical waveguide microfluid chip based on CMOS image sensing, include: the optical waveguide and the microchannel, the optical waveguide is used for leading light into the microchannel along the horizontal direction, still include: the CMOS image sensing layer, the lower cladding layer, the waveguide layer and the upper cladding layer are arranged from bottom to top in sequence; the waveguide layer is a silicon nitride material formed at a deposition temperature of 25-150 ℃ and is used for forming an optical waveguide; the micro channel penetrates through the upper cladding layer, the waveguide layer and the lower cladding layer from top to bottom to expose the CMOS image sensing layer; the lower cladding layer is made of a polymer material with a thickness of 15-30 μm, the upper cladding layer is made of a polymer material with a thickness of 15-30 μm, and the width of the micro channel is 10-100 μm. Has the advantages that: the silicon nitride optical waveguide with adjustable optical performance is deposited on the CMOS image sensing layer and the high polymer material at low temperature, so that the CMOS image sensing layer is not damaged, the preparation work of adjusting a collecting light path and the like in an experiment is reduced, and the experiment efficiency is improved; the portability of the detection system is improved, and the application scenes of the system are greatly increased.

Description

Optical waveguide microfluid chip based on CMOS image sensing

Technical Field

The invention relates to an optical waveguide microfluid chip based on CMOS image sensing, in particular to an optical waveguide microfluid biological detection chip based on CMOS image sensing.

Background

In modern biochemical analysis procedures, high-throughput detection devices have been widely used. Most of these devices use biochips based on microfluidic technology or microwell arrays, loaded in high performance optical systems, to perform analysis of biological samples of different sizes, such as nucleic acids, proteins, viruses, bacteria, cells, etc. The design of these optical systems is usually based on complex geometric optics, which is bulky, costly, requires optical alignment, and is costly to maintain.

In the precise medical age, miniaturized, high-performance, low-cost and mobile integrated analysis systems are of great concern. In particular, the lab on chip concept has advanced a lot of progress in manipulating a biological sample based on a microfluidic technology after decades of development, but a real lab on chip system still lacks an integrated system for chip-level on-chip optical detection and analysis of a high-throughput biological sample on a micro-nano scale.

CMOS image sensors are active pixel sensors that utilize CMOS semiconductors, where a corresponding circuit is located near each photosensor to directly convert light energy into a voltage signal. Unlike the CCD, which is a light sensing coupling element, it does not involve signal charges. Under the same condition, the number of CMOS image sensor elements is relatively less, the power consumption is lower, the data throughput speed is higher than that of a CCD, the signal transmission distance is shorter than that of the CCD, the capacitance, the inductance and the parasitic delay are reduced, and the data output is faster by adopting an X-Y addressing mode. The data output rate of a CCD typically does not exceed 70 million pixels per second, whereas a CMOS can achieve 100 million pixels per second.

Materials such as optical silicon nitride films and the like are deposited on the high molecular polymer and the CMOS image sensor, wherein the integrated optical device taking SiN as the waveguide can be separated from a silicon or glass substrate by the flexible substrate formed by the high molecular polymer, and the polymer has certain ductility, so that the application range of the integrated optical device taking SiN and the like as the waveguide is greatly enlarged; the CMOS image sensor can directly form a spectrum or a graph image, can replace an optical signal collecting device and a spectrum monitoring device such as a laboratory microscope and the like, can reduce the preparation work of adjusting a collecting light path and the like in an experiment, and improves the experiment efficiency; the portability of the detection system can be improved, and the application scenes of the system are greatly increased.

The film is deposited on the high molecular polymer and the CMOS image sensor, the lower the deposition temperature is needed to be, the better the deposition temperature is, so as not to damage the molecular structure of the polymer and the CMOS image sensor, while the growth temperature of the SiN film which is mainstream at present is about 400 ℃, and is still too high, so that the high molecular polymer is easily softened and melted, and the CMOS image sensor is easily damaged.

Disclosure of Invention

The device aims to solve a series of new requirements of miniaturization, mobility, integration and the like of the modern biochemical analysis instrument which is large in size and high in cost and meets the requirements of the precise medical era. The chip-level optical detection and analysis system is produced by an integrated circuit mass production process, the functions of the traditional optical system are realized by an integrated optical or on-chip optical device, a low-temperature optical guide manufacturing process is adopted to form an optical waveguide layer on a high-molecular polymer material and a CMOS image sensing layer, softening, hardening and melting of the high-molecular polymer material and damage to a CMOS image sensor are avoided, the replacement of the CMOS is utilized, the preparation work of adjusting a collection optical path and the like in an experiment is reduced, and the experiment efficiency is improved; the portability of the detection system is improved, and the application scenes of the system are greatly increased; the conventional desktop or even large-scale optical system can be reduced to the chip size, the equivalent or even more excellent analysis performance is ensured, the high-flux chip-level optical detection and analysis integrated system of the biological sample under the micro-nano scale is realized, and the system cost is greatly reduced.

The invention provides an optical waveguide microfluid chip based on CMOS image sensing, which comprises: an optical waveguide for guiding light into a microchannel in a horizontal direction, characterized in that:

further comprising: the CMOS image sensing layer, the lower cladding layer, the waveguide layer and the upper cladding layer are arranged from bottom to top in sequence; the waveguide layer is a silicon nitride material formed at a deposition temperature of 25-150 ℃, and the waveguide layer is used for forming the optical waveguide;

the micro channel penetrates through the upper cladding layer, the waveguide layer and the lower cladding layer from top to bottom to expose the CMOS image sensing layer;

the lower cladding is made of a high polymer material with the thickness of 15-30 mu m, the upper cladding is made of a high polymer material with the thickness of 15-30 mu m, and the width of the micro-channel is 10-100 mu m.

Preferably, a plurality of the optical waveguides are parallel to each other to guide light into the micro flow channel, and the width of the optical waveguides is 300 to 600 nm.

Preferably, the entire or a majority of the waveguide layers form a slab of the optical waveguide.

Preferably, the waveguide layer has a thickness of 150-1000 nm.

Preferably, the optical waveguide further comprises an incident grating made of silicon nitride material to form a coupled optical waveguide with the optical waveguide, and the light above the upper cladding is guided into the optical waveguide until the micro channel is guided; the incident grating protrudes from the waveguide layer and extends upwards into the upper cladding layer.

Preferably, a plurality of said coupling optical waveguides are included, parallel to each other.

Preferably, the thickness of the waveguide layer is 150nm-1000nm, and the width of the coupling optical waveguide is 300-600 nm.

Preferably, an optical fiber is further included, the optical fiber being optically connected to the optical waveguide.

Preferably, the refractive index of the waveguide layer is 1.75-2.2.

Preferably, the high molecular polymer material is SU-8 resin, polyimide, polydimethylsilane, polyethylene or benzocyclobutene.

The invention provides an optical waveguide microfluid chip based on CMOS image sensing, which has the following beneficial effects: the silicon nitride optical waveguide with adjustable optical performance is deposited on the CMOS image sensing layer and the high polymer material at low temperature, so that the CMOS image sensing layer is not damaged, the preparation work of adjusting a collecting light path and the like in an experiment is reduced, and the experiment efficiency is improved; the portability of the detection system is improved, and the application scenes of the system are greatly increased.

Drawings

FIGS. 1 a-d show the manufacturing process of the optical waveguide micro-fluid chip based on CMOS image sensing according to the present invention;

FIGS. 2 a-e are the manufacturing process of the coupled optical waveguide microfluidic chip based on CMOS image sensing according to the present invention;

FIG. 3 is a top view of FIG. 1;

fig. 4 is a top view of the fig. 1 sheet optical waveguide.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings.

In the drawings, the dimensional ratios of layers and regions are not actual ratios for the convenience of description. When a layer (or film) is referred to as being "on" another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may also be present. In addition, when a layer is referred to as being "under" another layer, it can be directly under, and one or more intervening layers may also be present. In addition, when a layer is referred to as being between two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present. Like reference numerals refer to like elements throughout. In addition, when two components are referred to as being "connected," they include physical connections, including, but not limited to, electrical connections, contact connections, and wireless signal connections, unless the specification expressly dictates otherwise.

The invention provides a scheme of a horizontal optical waveguide and microfluidic channel integrated module, which is used for quickly constructing a chip-level on-chip optical detection chip of a high-flux biological sample under a micro-nano scale. Here, the horizontal optical waveguide means an optical waveguide for guiding light into a microchannel in a horizontal direction.

The invention provides an optical waveguide microfluid chip based on CMOS image sensing, as shown in figures 1d, 2 e-4, comprising: an

optical waveguide

1311, 1312 … 131n and a microchannel 2, the optical waveguide 1311 being configured to guide light into the microchannel 2 in a horizontal direction, characterized in that:

further comprising: the CMOS image sensing layer 18, the lower cladding layer 141, the waveguide layer 13 and the upper cladding layer 142 are arranged from bottom to top in sequence; the waveguide layer 13 is a silicon nitride material formed at a deposition temperature of 25-150 ℃, and a silicon nitride optical waveguide is formed on the CMOS image sensing layer and the high polymer material by a low-temperature growth process, so that the CMOS image sensing layer is not damaged, the preparation work of adjusting a collecting light path and the like in an experiment is reduced, and the experiment efficiency is improved; the portability of the detection system is improved, the application scenes of the system are greatly increased, and the waveguide layer 13 is used for forming the optical waveguide 1311;

the micro flow channel 2 penetrates through the upper cladding layer 142, the waveguide layer 13 and the lower cladding layer 141 from top to bottom to expose the CMOS image sensing layer 18;

the lower cladding 141 is a polymer material with a thickness of 15 to 30 μm, the upper cladding 142 is a polymer material with a thickness of 15 to 30 μm, and the width of the microchannel 2 is 10 to 100 μm; the traditional desktop or even large-scale optical system is reduced to the size of a chip, the equal or even more excellent analysis performance is ensured, the high-flux chip for detecting the biological sample under the micro-nano scale is realized, and the system cost is greatly reduced.

The surface of the CMOS image sensing layer 18 is provided with a filter layer (not shown)

Wherein the light source direction is different according to the introduction of the optical waveguide assembly 131, such as: fig. 1d illustrates the introduction of the light source from an optical fiber (not shown) at the left end of the optical waveguide assembly 131, and fig. 2e illustrates the introduction of the light source from above the optical waveguide assembly 131, respectively.

Fig. 1d, the present optical waveguide microfluidic chip with light source introduced from the optical fiber (not shown) at the left end of the optical waveguide set 131, is described as follows:

as shown in fig. 1d, the optical waveguide set 131 in the optical waveguide microfluidic chip may comprise only one optical waveguide.

As shown in fig. 1d and 3, the optical waveguide set 131 on one microfluidic includes several, e.g. n,

optical waveguides

1311, 1312 … 131n parallel to each other to guide light into the microchannel 2 in the horizontal direction, in the actual detection, for biomolecules with different labels in the microchannel 2, the

optical waveguides

1311, 1312 … 131n can guide light with wavelengths λ 1, λ 2 … λ n into the microchannel 2 in the horizontal direction, respectively, and the excitation of labeled biomolecules 21 with different labels by light with different wavelengths can simultaneously identify these biomolecules, while the non-excited biomolecules 20 in the excitation light field guided by the

optical waveguides

1311, 1312 … 131n will not be identified, and the non-excited biomolecules 20 are non-labeled biomolecules or labeled biomolecules that are not excited but are located outside the light field; wherein, as shown in FIG. 3, the widths of the

optical waveguides

1311, 1312 … 131n are 300-600 nm.

As shown in fig. 4, the whole or most of the waveguide layer 13 forms a sheet-shaped optical waveguide 1311, and the excitation light field introduced by the sheet-shaped optical waveguide 1311 can reduce the background light signal in the detection-labeled biomolecule, thereby greatly improving the detection rate of the small biomolecule.

As shown in fig. 3 to 4, the thickness of the waveguide layer 13 is 150 to 1000nm, i.e. the thickness of the

optical waveguides

1311, 1312 … 131n in fig. 1d and 3 to 4 is 150 to 1000 nm.

Wherein the optical fiber (not shown) is optically connected to the optical waveguide set 131, and further optically connected to the

optical waveguides

1311, 1312 … 131n in the optical waveguide set 131.

Fig. 2e, the present optical waveguide microfluidic chip with light source introduced from above the optical waveguide assembly 131, is described as follows:

as shown in fig. 2e, an incident grating (not shown) of silicon nitride material is further included to form a coupled optical waveguide with the

optical waveguides

1311, 1312 … 131n, and the light above the upper cladding 142 is guided into the coupled optical waveguide until being guided into the microchannel 2 in the horizontal direction, where the upper cladding 142 is a light-transmissive layer; the entrance grating protrudes from the waveguide layer 13 and extends up into the upper cladding layer 142.

As shown in fig. 2e and fig. 3, the optical waveguide set 131 on one microfluidic includes a plurality of, e.g. n, coupling

optical waveguides

1311, 1312 … 131n parallel to each other to guide light into the microchannel 2 in the horizontal direction, in the actual detection, for biomolecules with different labels in the microchannel 2, the coupling

optical waveguides

1311, 1312 … 131n can guide light with wavelengths λ 1, λ 2 … λ n into the microchannel 2 in the horizontal direction, respectively, and the labeled biomolecules 21 with different labels can be simultaneously identified by exciting the labeled biomolecules with light with different wavelengths, while the non-excited biomolecules 20 in the excitation light field guided by the coupling

optical waveguides

1311, 1312 … 131n will not be identified, and the non-excited biomolecules 20 are normal cells without labeling or biomolecules that are labeled but outside the light field and are not excited; wherein the coupling

optical waveguides

1311, 1312 … 131n have a width of 300-600nm, as shown in fig. 3, and wherein the waveguide layer 13 has a thickness of 150-1000nm, as shown in fig. 2 e.

In the invention, the high polymer material is SU-8 resin, polyimide, polydimethylsilane, polyethylene or benzocyclobutene.

In the invention, the silicon nitride waveguide layer 13 is a silicon nitride film layer with the thickness of 150nm-1000nm formed at the low temperature of 25-150 ℃ of deposition temperature, so that the lower cladding 141 of a softening, hardening or melting high polymer material and the damage to the CMOS image sensing layer 18 are avoided, the preparation work of adjusting a collecting light path and the like in an experiment is reduced, and the experiment efficiency is improved; the portability of the detection system is improved, and the application scenes of the system are greatly increased; the refractive index of the silicon nitride waveguide layer 13 is 1.75-2.2. The silicon nitride film may be a film having a uniform refractive index, or may be a film having a non-uniform refractive index, such as a silicon nitride film having a layered refractive index structure.

The optical waveguide microfluid chip provided by the invention has the beneficial effects that: the silicon nitride optical waveguide with adjustable optical performance is deposited on the CMOS image sensing layer and the high polymer material at low temperature, so that the CMOS image sensing layer is not damaged, the preparation work of adjusting a collecting light path and the like in an experiment is reduced, and the experiment efficiency is improved; the portability of the detection system is improved, and the application scenes of the system are greatly increased.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. An optical waveguide microfluidic chip based on CMOS image sensing, comprising: an optical waveguide for guiding light into a microchannel in a horizontal direction, characterized in that:

2. The chip of claim 1, wherein a number of said optical waveguides are parallel to each other to guide light into said microchannel, said optical waveguides having a width of 300-600 nm.

3. The chip of claim 1, wherein the entire or a majority of the waveguide layers form a slab of the optical waveguides.

4. The chip of any one of claims 1 to 3, wherein the waveguide layer has a thickness of 150 to 1000 nm.

5. The chip of claim 1, further comprising an incident grating of silicon nitride material to form a coupled optical waveguide with the optical waveguide, and to guide light above the upper cladding layer into the optical waveguide until the micro flow channel is introduced; the incident grating protrudes from the waveguide layer and extends upwards into the upper cladding layer.

6. The chip of claim 5, comprising a plurality of said coupling optical waveguides parallel to each other.

7. The chip of claim 5, wherein the waveguide layer has a thickness of 150nm to 1000nm, and the coupling optical waveguide has a width of 300 nm to 600 nm.

8. The chip of claim 1, further comprising an optical fiber optically connected to the optical waveguide.

9. The chip of claim 1, wherein the index of refraction of the waveguide layer is 1.75-2.2.

10. The chip of claim 1, wherein the polymeric material is SU-8 resin, polyimide, polydimethylsilane, polyethylene, or benzocyclobutene.