CN102975318B

CN102975318B - Method for preparing PDMS chip including both square and arc-shaped channel

Info

Publication number: CN102975318B
Application number: CN201210438752.7A
Authority: CN
Inventors: 秦建华; 马静云; 姜雷; 张旭
Original assignee: Dalian Institute of Chemical Physics of CAS
Current assignee: Dalian Institute of Chemical Physics of CAS
Priority date: 2012-11-06
Filing date: 2012-11-06
Publication date: 2015-03-04
Anticipated expiration: 2032-11-06
Also published as: CN102975318A

Abstract

A method for preparing a PDMS chip including both square and arc-shaped channels comprises the following steps: clamping an SU-8 male mold of a cross-linked state prepared by standard photolithography with liquid PDMS to obtain a PDMS female mold with an inverted male mold pattern after the PDMS is cured; clamping the female mold PDMS with the solid uncross-linked SU-8 photoresist, heating the photoresist by a vacuum oven to make the photoresist be in a fluid state to fill the PDMS channels to obtain the uncrosslinked SU-8 male mold; selectively exposing the uncrosslinked SU-8 male mold to make the SU-8 male mold partially crosslink to form square protrusion portions; heating the male mold for some time to make the uncrosslinked portions be arc-shaped; performing a fully exposed crosslinking reaction, post-baking, solidifying the mold to get the stereotyped SU-8 square and arc-shaped male mold; and pouring with PDMS, curing, demolding to get the PDMS chip including both square and arc-shaped channels. The chip produced by the present invention is applied to preparation of a micro-fluidic chip liquid channel layer integrated with pneumatic micro-valves. The SU-8 male mold prepared by the invention is not easy to peel off from substrates. The radian of the PDMS chip arc-shaped channel is controllable. The simple and stable method is provided for the preparation of complex chips.

Description

A kind of simultaneously containing preparation method that is square, curved channel PDMS chip

Technical field

The invention belongs to the preparation method field of micro-fluidic chip, be specifically related to a kind of simultaneously containing preparation method that is square, curved channel PDMS chip.

Background technology

Method of molding is the main method making high molecular polymer chip at present, mainly obtains mould by photoresist and on mould, solidifies the method that liquid high polymer obtains having micro-structured chip.The mold materials that laboratory is commonly used is that SU-8 bears glue or positive glue, and high molecular polymer is then based on dimethyl silicone polymer (PDMS).Wherein SU-8 is a kind of conventional epoxy-based negative photoresist in MEMS technology, there is excellent mechanics, optical property and resistance to chemical corrosion, particularly, (can there is flow deformation when heating in material to the thermoplasticity had time uncrosslinked based on it, the character of definite shape can be kept after cooling) and the characteristic of ultraviolet photo-initiated crosslinking, the three-dimensional geometrical structure of formpiston can be regulated; PDMS can with high fidelity positive replica pattern.But the PDMS chip utilizing SU-8 formpiston to reverse out is master mainly with right angle square duct, some chip application system inapplicable.As in the chip being integrated with pump valve structure, fluid path layer passage if right angle is square, when the generation deformation of PDMS film, can not closed channel completely, still have part liquid and flow through; For continuous synthesis microsphere particle and micro fibre material, right angle square duct is also not bery applicable, reason is that the curved-surface structure of microsphere particle and microfibre and the geometric configuration of right angle square duct differ greatly, and easily causes synthetic material stagnate in passage and blocked.Prepare in the work of curved channel at great majority, have employed positive photoresist " Reflow " technology, but this processing step is complicated and success rate is low.Therefore, the PDMS chip with passage three-dimensional structure flexibly can meet the demand of various array experiment better; According to the character of SU-8 and PDMS, preparation containing square, curved channel PDMS chip, can promote the extensive use of chip simultaneously.

Summary of the invention

The object of this invention is to provide a kind of simultaneously containing preparation method that is square, curved channel PDMS chip, the method utilizes heat, the light plasticity of SU-8 and PDMS, prepares square, the simultaneous PDMS chip of curved channel.

The invention provides and provide a kind of simultaneously containing preparation method that is square, curved channel PDMS chip, the method step is as follows:

(1) preparation of crosslinking condition SU-8 formpiston: by the SU-8 formpiston of standard photolithography preparation containing microchannel pattern;

(2) preparation of former PDMS: by the liquid PDMS clamping of crosslinking condition SU-8 formpiston and certain thickness (100 microns to 150 microns), after PDMS solidification, the former PDMS of the formpiston pattern that obtains after unlatching reversing;

(3) preparation of the SU-8 formpiston of uncrosslinked state: by former PDMS and 150 micron of solid-state uncrosslinked SU-8 photoresist clamping to 300 micron thickness (preferably 150 microns), vacuum drying oven heating makes photoresist be that flowable state is full of PDMS passage, opens the SU-8 formpiston obtaining uncrosslinked state after cooling;

(4) formation of the square formpiston of SU-8: to the selective exposure of SU-8 formpiston of the uncrosslinked state that step (3) obtains, make its partial cross-linking obtain square protrusion part;

(5) formation of SU-8 arc formpiston: by uncrosslinked for part SU-8 formpiston heating certain hour, obtain the shape of template of arc; Through exposure cross-linking reaction, after dry, hard mould obtain shape SU-8 arc formpiston;

(6) contain SU-8 template that is square, arc formpiston while step (4) and (5) jointly being obtained to build with PDMS, solidification, the demoulding, sealing-in, obtain containing PDMS chip that is square, curved channel.

Provided by the invention simultaneously containing preparation method that is square, curved channel PDMS chip, contained by crosslinking condition SU-8 formpiston prepared by described step (1) standard photolithography, micro-protuberance is that right angle is square.

Provided by the invention a kind of simultaneously containing preparation that is square, curved channel PDMS chip, in described step (2), former PDMS attaches on the glass sheet, so that follow-up continuation reverse.

Provided by the invention simultaneously containing preparation method that is square, curved channel PDMS chip, in described step (3), the solid-state uncrosslinked SU-8 photoresist of 150 micron thickness need remove bubble in advance, clamp as in vacuum drying oven with the PDMS former attached on the glass sheet, be pumped down to after vacuum until oven interior, be warming up to 100 DEG C and maintain 5 minutes, taking out after cooling.

Provided by the invention simultaneously containing preparation method that is square, curved channel PDMS chip, in described step (3), heating-up temperature is 80 DEG C to 100 DEG C.

Provided by the invention simultaneously containing preparation method that is square, curved channel PDMS chip, in described step (4), to the part of the selective exposure of this uncrosslinked SU-8 formpiston, square protrusion part is fixed to owing to there occurs cross-linking reaction, due to uncrosslinked, also there is thermoplasticity and light sensitivity in unexposed position.

Provided by the invention simultaneously containing preparation method that is square, curved channel PDMS chip, in described step (5), heating-up temperature is 40 DEG C to 60 DEG C (preferably 50 DEG C), and by the regulation and control to heat time (5 minutes to 30 minutes), can control uncrosslinked partial arcs size.

Provided by the invention simultaneously containing preparation method that is square, curved channel PDMS chip, by to the selective exposure of SU-8 formpiston and the subsequent heat with thermoplasticity and light sensitivity, be there is jut that is square and arc simultaneously, then be reversed to simultaneously containing PDMS chip that is square, curved channel.

Creativeness of the present invention is: provide a kind of simultaneously containing preparation method that is square, curved channel PDMS chip, be expected to the PDMS chip preparation applying to this mode to have passage three-dimensional structure flexibly, meet the demand of various array experiment better.

The invention has the advantages that: 1, process simple and fast; 2, the three-dimensional configuration selecting local channel can experimentally be needed; 3, the radian of curved channel is controlled.

Accompanying drawing explanation

Fig. 1 the present invention preparation is simultaneously containing process constructed profile that is square, curved channel PDMS chip; Wherein 1-8 represents step respectively: sheet glass clamping PDMS female mould forming, obtains PDMS former, close, heating in vacuum with thick plastic clip after breakdown, subregion exposure after breakdown, 50 degree of heating, and ultraviolet exposes sizing entirely, and PDMS chip is shaping; In step 1, represent sheet glass, PDMS, SU-8 layer, sheet glass from top to bottom respectively;

The non-aeration status profile of PDMS chip of what Fig. 2 utilized the present invention to prepare the be integrated with micro-valve of arcuate structure, wherein, 1 to 3 represents fluid path layer, PDMS film and gas circuit layer respectively;

The PDMS chip aeration status profile of what Fig. 3 utilized the present invention to prepare the be integrated with micro-valve of arcuate structure, wherein, 1 to 3 represents fluid path layer, PDMS film and gas circuit layer respectively;

Iiquid residence state during what Fig. 4 utilized the present invention to prepare be integrated with micro-valve Close All in the PDMS chip of the micro-valve of arcuate structure.

Detailed description of the invention

The following examples will be further described the present invention, but not thereby limiting the invention.

Embodiment 1:

According to step as shown in Figure 1, further illustrate implementation step and the substantive distinguishing features of the method:

(1) prepare by standard photolithography the SU-8 formpiston that crosslinking condition contains microchannel pattern, contained micro-protuberance is that right angle is square;

(2) preparation of former PDMS: by crosslinking condition SU-8 formpiston and certain thickness liquid PDMS clamping, after PDMS solidification, the former PDMS of the formpiston pattern that obtains after unlatching reversing, former PDMS attach on the glass sheet and silanization treatment, are beneficial to the follow-up demoulding;

(3) preparation of the SU-8 formpiston of uncrosslinked state: the solid-state uncrosslinked SU-8 photoresist of 150 micron thickness removes bubble in advance, itself and the PDMS former attached on the glass sheet are clamped as in vacuum drying oven, be pumped down to after vacuum until oven interior, be warming up to 100 DEG C and maintain 5 minutes, vacuum drying oven heating makes photoresist be that flowable state is full of PDMS passage, opens the SU-8 formpiston obtaining uncrosslinked state after cooling;

(4) formation of the square formpiston of SU-8: to the selective exposure of this uncrosslinked SU-8 formpiston, be fixed to square protrusion part owing to there occurs cross-linking reaction, unexposed position, due to uncrosslinked, also exists thermoplasticity and light sensitivity;

(5) formation of SU-8 arc formpiston: by uncrosslinked for part SU-8 formpiston 50 DEG C heating certain hour, by the regulation and control to the heat time, uncrosslinked partial arcs size can be controlled, through exposure cross-linking reaction, after dry, hard mould obtain shape SU-8 formpiston;

(6) build and obtain containing PDMS chip that is square, curved channel with PDMS, solidification, the demoulding, sealing-in.

Embodiment 2:

According to step as shown in Figure 1, prepare the fluid path layer be integrated with in micro-valve arrangement chip.

(4) formation of the square formpiston of SU-8: to the selective exposure of this uncrosslinked SU-8 formpiston, be fixed to square protrusion part owing to there occurs cross-linking reaction; And micro-valve correspondence position black masks is covered and do not exposed, uncrosslinked due to it, also there is thermoplasticity and light sensitivity, arc can be formed and fixing;

(5) formation of SU-8 arc formpiston: by SU-8 formpiston 50 DEG C heating 20 minutes, the SU-8 of micro-valve correspondence position was curved, through the sizing of exposure cross-linking reaction, after dry, hard mould obtains final SU-8 fluid path layer formpiston;

(6) build and obtain containing fluid path layer PDMS chip that is square, curved channel with PDMS, solidification, the demoulding, sealing-in.

(7) by above-mentioned fluid path layer chip and PDMS film and gas circuit layer chip involution, as Fig. 2, investigate micro-valve and close efficiency.Because fluid path passage is arc, when the generation deformation of PDMS film, can closed channel completely, do not have liquid and flow through, the liquid in chip is temporarily in and arrheas state, as shown in Figures 3 and 4.

Claims

1., simultaneously containing a preparation method that is square, curved channel PDMS chip, it is characterized in that: concrete grammar step is as follows:

Contained by crosslinking condition SU-8 formpiston prepared by described standard photolithography, micro-protuberance is that right angle is square;

(2) preparation of former PDMS: by crosslinking condition SU-8 formpiston and the clamping of certain thickness liquid PDMS film, after PDMS solidification, the former PDMS of the formpiston pattern that obtains after unlatching reversing;

The thickness of described liquid PDMS film is 100 microns to 150 microns;

(3) preparation of the SU-8 formpiston of uncrosslinked state: by former PDMS and 150 micron of solid-state uncrosslinked SU-8 photoresist clamping to 300 micron thickness, vacuum drying oven heating makes photoresist be that flowable state is full of PDMS passage, opens the SU-8 formpiston obtaining uncrosslinked state after cooling; Described heating-up temperature is 80 DEG C to 100 DEG C;

The thickness of described solid-state uncrosslinked SU-8 photoresist is 150 microns;

(5) formation of SU-8 arc formpiston: by the SU-8 formpiston of uncrosslinked for part state heating certain hour, obtain the shape of template of arc; Through exposure cross-linking reaction, after dry, hard mould obtain shape SU-8 arc formpiston;

The described heat time is 5 minutes to 30 minutes; Described heating-up temperature is 40 DEG C to 60 DEG C;