CN100593508C

CN100593508C - Method for processing periodic nano structure device

Info

Publication number: CN100593508C
Application number: CN200610113830A
Authority: CN
Inventors: 吴文刚; 韩翔; 郝一龙; 王阳元
Original assignee: Peking University
Current assignee: Peking University
Priority date: 2006-10-18
Filing date: 2006-10-18
Publication date: 2010-03-10
Anticipated expiration: 2026-10-18
Also published as: CN1944237A

Abstract

The process of making periodical device in nanometer structure includes the following steps: 1. preparing and washing substrate and forming structure layer pattern; 2. side wall depositing one kind ofmaterial different from that of the structure layer to the side wall of the structure layer and anisotropic etching to form the side wall; and 3. repeating the step 2 with different material for several times to form the periodical device in nanometer structure on the substrate. Periodical nanometer grating, nanometer lattice, nanometer column, etc made based on the technology of the present invention may be applied widely as optical device, biomedical detecting device, sensing device, electronic device, etc.

Description

A kind of method of processing periodic nano structure device

Technical field

The present invention relates to a kind of method of processing periodic nano structure device.

Background technology

The periodic nano-structure device is meant according to certain rule and arranges that physical dimension reaches the device of nanoscale on one dimension, bidimensional even three-dimensional, has extensively, important use is worth.For example, periodically nanometer grid structure can be applicable to former wavelet inertia device and sub-wavelength optics; Periodically nanometer " grid " structure or columnar arrays structure can be applicable to microfluid, realize filtration, the separation of nanoscale object such as certain biomone; High density periodically nano-pillar array structure can be applicable to novel high-density memory and advanced nano mechanical device; These periodic nano-structures also can be used as the mould of nano impression; Or the like.Therefore, how the processing and manufacturing periodic nano-structure is extremely interested, the important thing that gives more sustained attention of people in recent years, also is one of research focus of nanosecond science and technology.At present, general " from top to bottom " mode manufacturing cycle nanostructured that adopts, but this processing method need rely on most advanced and sophisticated exposure or etching apparatus, because costing an arm and a leg of this class tip device, quantity seldom, and being mostly the serial cooked mode, this makes the processing capacity of periodic nano-structure be very limited, and has greatly influenced its applying in each side such as research, exploitation, products.

The side wall deposition technique is shape-retaining ability deposit and an anisotropic etching technology of utilizing traditional microelectronic technique, will support a kind of processing method that the pattern side wall material keeps.The height of side-wall material is decided by to support the figure height, and width is decided by the thickness of deposit film.

Summary of the invention

The method that the purpose of this invention is to provide a kind of processing periodic nano structure device.

The method of processing periodic nano structure device provided by the present invention comprises the steps:

1) prepare and clean selected substrate, figure dissolves structure sheaf on substrate;

2) select the another kind of material different, carry out the side wall deposition in the side of described structure sheaf, form a side wall in the side of described structure sheaf after the anisotropic etching with described structural material;

3) in described side wall side with different material repeating steps 2), through repeatedly deposition, etching, on described substrate, form described periodic nano-structure device.

Wherein, substrate commonly used is a silicon substrate.The side wall deposition adopts shape-retaining ability deposit (as low-pressure chemical vapor phase deposition) method.

The present invention also provides a kind of column periodic nano-structure device, and the top of column structure is a water wetted material, and bottom and substrate are hydrophobic material.

Wherein, water wetted material can be selected silica for use, and described hydrophobic material can be selected silicon for use.

The present invention can rely on the periodic structure that thin-film deposition is realized nanoscale based on the side wall deposition technique under the prerequisite that is not subjected to the etching condition restriction, broken through the restriction of normal optical carving technology.And, the side wall deposition technique is because it stems from microelectronic manufacturing technology, can realize batch, parallel processing easily, and has a good control accuracy, also can be by changing technological parameter such as film thickness etc. the parameter of adjustment cycle nanostructured easily, improved the production efficiency and the integrated level of nanostructured greatly, helped reducing industrial production cost, promoted the research of nano-device and produce exploitation.The periodicity nanometer grid of making based on the present invention, nanometer " grid ", nano-pillar etc. can be applicable to fields such as optics, biomedical detection means, senser element, electronic device.

Description of drawings

Figure 1A-Fig. 1 G, Figure 1A '-Fig. 1 G ' is respectively the profile and the vertical view of structure in embodiment 1 process;

Fig. 2 is the schematic three dimensional views of embodiment 1 resulting structures;

Fig. 3 A-Fig. 3 D, Fig. 3 A '-Fig. 3 D ' is respectively the profile and the vertical view of structure in embodiment 2 process;

Fig. 4 is the schematic three dimensional views of embodiment 2 resulting structures;

Fig. 5 A-Fig. 5 C, Fig. 5 A '-Fig. 5 C ' is respectively the profile and the vertical view of structure in embodiment 3 process;

Fig. 6 is the schematic three dimensional views of embodiment 3 resulting structures;

Fig. 7 A-Fig. 7 D is the electromicroscopic photograph of gained nano-device structure;

Fig. 8 A, Fig. 8 A ' are the profile and the vertical view of the cantilever beam of embodiment 4 band columnar nano-structure;

Fig. 9 utilizes embodiment 5 resulting structures to shift, extract the schematic diagram of biomaterial;

Figure 10 is the electromicroscopic photograph after target solution is extracted on embodiment 5 nano-pillar tops.

The specific embodiment

The method of processing periodic nano structure device of the present invention, the major technique thinking is:

Substrate (as silicon chip) go up by the required structure sheaf of common photolithography patterning means definition structure side wall (as can polysilicon as structural material), (or claim sacrificial layer material by another kind of material then, silica membrane for example) deposit and anisotropic etching stay nanoscale sacrifice layer (silica) mask that is determined by film thickness in the structure sheaf side.Afterwards, deposit once more, etching structure layer material form the side wall that is made of structural material.Repeatedly repeat said process, in same plane, can form periodicity " grid " figure of nanoscale.

On this basis,, pile up, can process periodically nanometer " grid " structure by certain intersecting angle (as 90 degree) if adopt two-layer (or multilayer) periodically " grid " figure; If be that the downward etching of mask is somebody's turn to do " grid " material even backing material further, can form nanoscale column structure in the position in periodicity lines crosspoint with nanometer " grid ".

In the process, can change technological parameter according to the cycle and the cycle form of various periodic nano-structures, process is convenient, and can obtain the device of multiple version.Based on existing microelectronic manufacturing technology, above-mentioned technology can both obtain easily, and can obtain enough control accuracies.

The present invention can adopt multiple different materials to process, and only need satisfy the high selectivity of etching (or corrosion) material.The different materials of using always in the microelectronics industry has silica, polysilicon and silicon nitride etc.Below with silica and polysilicon as spacer material and structural material, silicon nitride is that example describes as protective material.At different application needs, processing step (for example back side corrosion) can also suitably be increased, so that integrated with other micrometer/nanometer structures.

The nano-device of embodiment 1, manufacturing cycle lattice structure

In the preparation process, the profile of structure such as Figure 1A-Fig. 1 G and and corresponding vertical view such as Figure 1A '-Fig. 1 G ', specific operation process is as follows:

1) prepares and cleans selected substrate 1.

2) thermal oxide or deposit silicon dioxide layer 2 are seen Figure 1A and Figure 1A ';

3) deposit polysilicon layer, photoetching forms required figure, and polysilicon is carried out etching, forms polysilicon structure layer 3, sees Figure 1B and Figure 1B ';

4) along polysilicon structure layer 3 another layer of guarantor's type deposit silica 21, see Fig. 1 C and Fig. 1 C ';

5) silica 21 of one deck deposit before the anisotropic etching stays silica side wall 22 in the polysilicon side, sees Fig. 1 D and Fig. 1 D ';

6) guarantor's type deposit one deck polysilicon, this layer of anisotropic etching polysilicon forms polysilicon side wall 32 again outside the anterior layer side wall, see Fig. 1 E and Fig. 1 E ';

7) Fig. 1 F and Fig. 1 F ' until forming required grid number, are seen in repeating step (5), (6);

8) selective etch (or corrosion) wherein a kind of material (silica side wall 22) stays another kind of spacer material (polysilicon side wall 32), promptly obtains having the periodically nano-device of network, sees Fig. 1 G and Fig. 1 G '.

Can operate the acquisition cavity overleaf accordingly to the gained nano-device as required, thereby form required transmission grid, schematic three dimensional views as shown in Figure 2.7 is substrate among the figure, and 8 is structure sheaf, and 9 is side wall.

The nano-device of embodiment 2, preparation network

Based on step 7) obtained device among the embodiment 1, can further process, form the nano-device of network, the profile of structure such as Fig. 3 A-Fig. 3 D and and corresponding vertical view such as Fig. 3 A '-Fig. 3 D ', specific operation process is as follows:

1) deposit sublevel polysilicon, photoetching forms required figure, and polysilicon is carried out etching, and removes photoresist, and sees Fig. 3 A and Fig. 3 A ';

2) repeat the foregoing description 1 step 4)-6), until forming required grid number, see Fig. 3 B and Fig. 3 B ';

3) back side forms back of the body chamber by photoetching, etching means such as (or corrosion), sees Fig. 3 C and Fig. 3 C ';

4) the front gluing is protected, and back side hydrofluoric acid corrode silicon dioxide removes photoresist, and stays required network, sees Fig. 3 D and Fig. 3 D '; Its schematic three dimensional views as shown in Figure 4.

The nano-device of embodiment 3, preparation column structure

Based on step 2 among the embodiment 2) obtained device, can further process, form the nano-device of network, the profile of structure such as Fig. 5 A-Fig. 5 C and and corresponding vertical view such as Fig. 5 A '-Fig. 5 C ', specific operation process is as follows:

1) deposit one deck silicon nitride 10, the photoetching desired zone, the silicon nitride, the polysilicon that adopt wet etching to expose, and remove photoresist, see Fig. 5 A and Fig. 5 A ';

2) anisotropic etching silica, control large tracts of land etching finishes, and only stays the figure in silica crosspoint, sees Fig. 5 B and Fig. 5 B ';

3) anisotropic etching silicon finally forms nano column array on silicon substrate, see Fig. 5 C and Fig. 5 C '.

Can select whether to erode earth silicon mask as required, schematic three dimensional views such as Fig. 6.By above-mentioned processing, promptly can obtain the nano-device of column structure, comprise substrate 41, bottom 42 and top 43, top 43 is connected on the substrate 41 by bottom 42, and the material of substrate 41 and bottom 42 is hydrophobic material, is silicon; The material at top 43 is a water wetted material, is silica.

Fig. 7 A-7D is the periodically electromicroscopic photograph of nano-device of gained, and Fig. 7 A is corresponding to the network of Fig. 3 D among the embodiment 2; Fig. 7 C is corresponding to embodiment 3 Fig. 5 B; Fig. 7 B and 7D are corresponding to Fig. 5 C among the embodiment 3.

Embodiment 4, on cantilever beam, process columnar nano-structure

The profile of the cantilever beam of band columnar nano-structure and vertical view are respectively as Fig. 8 A and Fig. 8 A ', and specific operation process is as follows:

1. the silicon chip that adopts SOI (or similar SOI) structure adopts the flow process of embodiment 3 to make the nanometer column structure as substrate, keeps the silica of capital end.

2. positive lithographic definition cantilever beam, etching is removed photoresist;

3. with the protection of silicon chip front gluing, graphical from the back side, erode away cavity, and the insulating barrier in the middle of the corrosion substrate;

4. the release cantilever beam that removes photoresist obtains this structure.

Embodiment 5, utilize the water wetted material on nano-pillar top to extract, shift micro-biological solution

Can adopt common photoetching, deep etching method on silicon substrate, produce grid type solution memory.The cantilever beam that has columnar nano-structure that utilizes embodiment 4 to be processed, and this grid type solution memory can be realized the extraction and the transfer of biofluid.Specific operation process is as follows:

1. grid type solution memory is injected required solution example on demand;

2. cantilever beam and needle point are submerged in the solution of required transfer;

3. cantilever beam is mentioned, because to have only the silica on nano-pillar top be water wetted material, all the other are hydrophobic material, so this target solution has only and is stored in the nano-pillar top on a small quantity;

4. shift cantilever beam to operating position, with the sticking target location that is placed on of the solution that extracts.

Operation chart can be with reference to figure 9.Figure 10 has provided the electromicroscopic photograph after the nano-pillar top extraction target solution.

Claims

1, a kind of method of processing periodic nano structure device comprises the steps:

1) prepares and cleans selected substrate (1);

2) deposit silicon dioxide layer;

3) deposit polysilicon layer, photoetching forms required figure, and polysilicon is carried out etching, forms the polysilicon structure layer;

4) along another layer of polysilicon structure layer guarantor type deposit silica;

5) silica of anisotropic etching step 4) stays the silica side wall in the polysilicon side;

6) guarantor's type deposit one deck polysilicon, this layer of anisotropic etching polysilicon forms polysilicon side wall again outside the anterior layer side wall;

7) repeat another layer of guarantor's type deposit silica, the silica of one deck deposit stays the silica side wall in the polysilicon side before the anisotropic etching; Guarantor's type deposit one deck polysilicon, this layer of anisotropic etching polysilicon forms the step of polysilicon side wall again outside the anterior layer side wall, until forming required grid number;

8) selective etch or corrode described polysilicon side wall and the silica spacer material in a kind of spacer material, stay another kind of spacer material, promptly obtain having the periodically nano-device of network.

2, method according to claim 1 is characterized in that: described substrate is a silicon substrate.

3, method according to claim 1 is characterized in that: the method for described guarantor's type deposit is a low-pressure chemical vapor phase deposition.