CN107703105A - The adjustable substrate of surface plasma performance and preparation method - Google Patents

Abstract

The invention relates to a substrate with adjustable surface plasmon properties and a preparation method. The substrate includes a PDMS substrate on which a noble metal film layer is deposited; the preparation method: using AAO as a template to transfer the surface structure to the PDMS substrate , so that the PDMS substrate has a nano-column array structure surface; deposit a noble metal film layer on the surface of the fabricated PDMS substrate; stretch the fabricated substrate: place the fabricated noble metal PDMS substrate flatly on a one-dimensional translation stretching In the clamp, one end of the substrate is fixed, and the other end is clamped on the movable platform, and the substrate can be stretched within the elastic range of PDMS along the moving direction of the mobile platform; the stretched substrate is tested: the plasma absorption on the surface of the stretched substrate The peak appears blue-shifted and the absorption intensity weakens. It shows that the substrate realizes tunable surface plasmon properties. The substrate manufacturing process of the invention is simple and efficient, the substrate has good sensitivity, high controllability and short process cycle.

Description

Substrate with adjustable surface plasmon properties and preparation method

technical field

The invention relates to a surface plasma performance adjustable technology, in particular to a novel substrate with adjustable surface plasma performance.

Background technique

Surface plasmon refers to the non-radiative localized electromagnetic mode formed by the mutual coupling of free electrons and incident photons on the metal surface. Under certain conditions, when the light wave is incident on the interface between the metal and the medium, the evanescent wave and the surface plasmon wave will resonate. This phenomenon is called surface plasmon resonance (Surface Plasmon Resonance, SPR). SPR technology has the advantages of high sensitivity, high resolution, and real-time analysis, so it has many potential application prospects, such as: biological and chemical sensing, optoelectronic devices, nonlinear optics, surface Raman enhancement and many other fields. The efficiency and strength of these applications are often closely related to the plasmon resonance wavelength. Theory shows that by changing the geometric shape, size, environmental factors and material composition of metal nanoparticles, the plasmon resonance frequency will also change accordingly. The research on SPR is mainly on the surface of noble metals, such as gold, silver, platinum and other noble metals, mainly because of their relatively stable properties and high electron loading density under general conditions. However, it is still a key issue to realize the tunable SPR performance by controlling the shape and size of noble metal particles.

PDMS (Polydimethylsiloxane, polydimethylsiloxane, commonly referred to as organosilicon) is a polymer organosilicon compound with optical transparency, optical properties, low surface energy, high gas permeability and good elasticity. PDMS is a viscous liquid in the liquid state, known as silicone oil; in the solid state, it is inert silica gel, which is non-toxic, hydrophobic, transparent and elastic. During the experiment, the main agent and the curing agent will be evenly mixed in a certain proportion, and then the air in the mixture will be discharged by vacuuming, and finally the PDMS will be cured by baking at a certain temperature for a certain period of time.

At present, the method of preparing and regulating SPR mainly uses colloidal metal particles or metal thin film annealing, but these processes are cumbersome, poor in repeatability, and high in cost. Therefore, by virtue of the elastic properties of PDMS, the gap between metal particles can be controlled by the stretching of noble metal PDMS substrates to achieve controllable SPR performance, which has high research value and practical significance.

Contents of the invention

In view of the disadvantages of complex preparation process, poor reproducibility and high cost in the existing methods for controlling surface plasmon resonance, the purpose of the present invention is to provide a substrate with adjustable surface plasmon properties and a preparation method to realize a simple and efficient substrate manufacturing process. The substrate has the advantages of good sensitivity, high controllability, and short process cycle.

For realizing the above object, technical scheme of the present invention is:

A substrate with adjustable surface plasmon properties comprises a PDMS substrate, on which a nano-pillar array structure of an AAO template is transferred, and a noble metal film layer is deposited on the PDMS substrate with a nano-pillar array structure.

Further, the material of the noble metal film layer is Ag, Au or Pt.

A method for preparing a substrate with adjustable surface plasmon properties, the specific steps are as follows:

(1) transfer the structure on the AAO template to the PDMS substrate, so that the surface of the PDMS substrate has a nanocolumn array structure;

(2) Depositing a noble metal film layer on the fabricated PDMS substrate to obtain a substrate with adjustable surface plasmon properties;

(3) Stretch the fabricated substrate with adjustable surface plasmon properties: place the fabricated noble metal PDMS substrate flatly in a one-dimensional translation stretching clamp, one end of the substrate is fixed, and the other end is clamped on a movable platform , so that the fabricated noble metal PDMS substrate is stretched for a certain length within the elastic range of PDMS along the moving direction of the mobile platform;

(4) Detecting the stretched substrate: detecting the absorption spectrum of the stretched substrate, and stretching the substrate can realize the regulation of surface plasmon properties.

Compared with the prior art, the present invention has the beneficial effects that: the substrate with controllable surface plasmon performance obtained by the present invention has low equipment requirements, low cost, simple process and short cycle, and the substrate has good It has high research value and application prospect for tuning surface plasmon properties.

Description of drawings

Fig. 1 is the flow chart of the preparation method of the substrate with controllable surface plasmon properties of the present invention;

Fig. 2 is a process schematic diagram of the substrate with controllable surface plasmon properties of the present invention,

Among them, (a) the PDMS mixture is overturned on the surface of the AAO template; (b) the PDMS substrate is cured; (c) the noble metal film is deposited on the PDMS substrate, and the fabricated substrate is stretched; (d) the stretched base;

Fig. 3 is the absorption spectrum diagram of the substrate with controllable surface plasmon properties of the present invention before stretching and after stretching,

Wherein, a in the figure represents the absorption curve of the substrate before stretching; b in the figure represents the absorption curve of the substrate after stretching.

detailed description

In order to make the technical means, creative features, goals and effects of the present invention easy to understand, the following examples will specifically describe a substrate with controllable surface plasmon properties and its preparation method according to the present invention in conjunction with the accompanying drawings. The scope of protection is not limited to the examples described below.

The substrate with adjustable surface plasmon properties of the present invention comprises a PDMS substrate and a noble metal film layer. A nano-pillar array structure of the AAO template is transferred on the PDMS substrate, and a noble metal film layer is deposited on the PDMS substrate with the nano-pillar array structure. The material of the noble metal film layer is Ag, Au or Pt.

As shown in Figure 1, the process flow of the substrate preparation method with adjustable surface plasmon properties of the present invention is as follows:

1) Transfer the structure of the AAO template to the PDMS substrate, then the surface of the PDMS substrate has a nanopillar array structure;

2) Deposit a noble metal film layer on the fabricated PDMS substrate to obtain a new type of substrate with adjustable surface plasmon properties;

3) Stretch the prepared substrate: Place the fabricated noble metal PDMS substrate flatly in a one-dimensional translation stretching clamp, one end of the substrate is fixed, and the other end is clamped on the movable platform, and the substrate moves along the moving direction of the mobile platform It can be stretched to a certain length within the elastic range of PDMS;

4) Detecting the stretched substrate: detecting the absorption spectrum of the stretched substrate.

Example 1:

Embodiment 1 elaborates the substrate preparation process of the present invention in combination with FIG. 2 . The specific operation steps are as follows:

(a) Pour the PDMS mixed solution prepared at 10:1 on the surface of the AAO template, and use the method of vacuuming to discharge the air in the mixed solution, so that the PDMS penetrates into the aperture of the AAO, see Figure 2(a);

(b) Bake at 80° C. for 3 hours to cure the PDMS, and peel off the cured PDMS to obtain a PDMS substrate with a nanocolumn array structure, as shown in Figure 2(b);

(c) Using the electron beam evaporation coating system, the vacuum degree is lower than 9.0×10 ^-4 Pa, depositing a noble metal film layer on the surface of the PDMS substrate to obtain a new type of substrate with adjustable surface plasmon properties, and the prepared substrate Stretching: Place the fabricated noble metal PDMS substrate flatly in a one-dimensional translation stretching clamp, one end of the substrate is fixed, the other end is clamped on the movable platform, and stretched within the elastic range of PDMS along the moving direction of the mobile platform to a certain extent length, see Figure 2(c);

(d) Obtain the stretched substrate, see FIG. 2(d), and detect the stretched substrate: detect the absorption spectrum of the stretched substrate.

This example specifically describes the inventive substrate with controllable surface plasmon properties, including a PDMS substrate and a noble metal film layer.

In this example, the noble metal film layer is located on the upper surface of the PDMS substrate.

In this example, the material of the noble metal film layer is silver thin film.

In this example, the thickness of the silver thin film is 8nm.

Example 2:

In this example, on the basis of Example 1, the absorption characteristics of the substrate with controllable surface plasmon properties are detected, that is, the absorption spectra of the noble metal PDMS substrate before and after stretching.

As shown in Figure 3, the absorption curves of the substrate of the present invention before and after stretching obtained in this example, wherein a in the figure represents the absorption curve of the substrate before stretching; b in the figure represents the absorption curve of the substrate after stretching. Comparing the absorption curves of a and b, after stretching the substrate for a certain length, the shape and size of the Ag particles will be affected, resulting in a blue shift of the absorption peak and a weakening of the absorption intensity. It shows that the prepared noble metal PDMS substrate has a good tuning effect and can meet the requirements of the substrate with controllable surface plasmon properties of the present invention.

The above embodiments are only basic descriptions of the concept of the present invention, and do not limit the present invention. Any equivalent transformation made according to the technical solution of the present invention belongs to the protection scope of the present invention.

Claims (3)

1. A substrate with adjustable surface plasmon properties, comprising a PDMS substrate, on the described PDMS substrate, a nanocolumn array structure with an AAO template is transferred, characterized in that: the PDMS substrate with the nanocolumn array structure is deposited with Precious metal film layer. 2. The substrate with adjustable surface plasmon properties according to claim 1, characterized in that: the material of the noble metal film layer is Ag or Au or Pt. 3. A method for preparing a substrate with adjustable surface plasmon properties according to claim 1 or 2, wherein the specific steps are as follows: 1) Transfer the structure on the AAO template to the PDMS substrate, so that the surface of the PDMS substrate has a nanopillar array structure; 2) Deposit a noble metal film layer on the fabricated PDMS substrate to obtain a substrate with adjustable surface plasmon properties; 3) Stretch the manufactured substrate with adjustable surface plasmon properties: place the fabricated noble metal PDMS substrate flatly in a one-dimensional translation stretching clamp, one end of the substrate is fixed, and the other end is clamped on a movable platform. Stretch the fabricated noble metal PDMS substrate for a certain length within the elastic range of PDMS along the moving direction of the mobile platform; 4) Detect the stretched substrate: detect the absorption spectrum of the stretched substrate, stretching the substrate can realize the regulation of surface plasmon properties.