Photodeposition method for fabricating a three-dimensional, patterned polymer microstructure

• US 6,200,737 B1
• Filed: 08/24/1995
• Issued: 03/13/2001
• Est. Priority Date: 08/24/1995
• Status: Expired due to Term

• Current Assignee: Trustees of Tufts College
• Original Assignee: Trustees of Tufts College
• Inventors: Healey, Brian G., Walt, David R.
• Primary Examiner(s): ANGEBRANNDT, MARTIN J
• Application Number:
  US08/519,062
• Time in Patent Office: 2,028 Days
• Field of Search: 430/1, 430/2, 430/320, 430/5, 430/321, 359/34, 359/35, 422/82.06, 422/82.11
• US Class Current: 430/320
• CPC Class Codes: G02B 6/06 the relative position of the fibres being the same at both ends, e.g. for transporting images
• CPC Class Codes: G03F 7/2008 characterised by the reflectors, diffusers, light or heat filtering means or anti-reflective means used
• CPC Class Codes: G03F 7/2043 with the production of a chemical active agent from a fluid, e.g. an etching agent; with meterial deposition from the fluid phase, e.g. contamination resists

Abstract

The present invention is a photodeposition methodology for fabricating a three-dimensional patterned polymer microstructure. A variety of polymeric structures can be fabricated on solid substrates using unitary fiber optic arrays for light delivery. The methodology allows micrometer-scale photopatterning for the fabricated structures using masks substantially larger than the desired dimensions of the microstructure.

Claims

1. A photodeposition method for fabricating a three-dimensional polymer microstructure of prearranged pattern and precise scale, said photo deposition method comprising the steps of:

furnishing at least one shaft of light energy of determinable wavelength, intensity, and exposure time;

supplying a preformed, unitary fiber optic array comprising a plurality of clad optical fiber strands disposed co-axially along their lengths and having two discrete optic array end surfaces each formed of multiple optical fiber strand end faces, said preformed, unitary optic array being of determinable configuration and dimensions, and said discrete optic array end surfaces presenting multiple optical fiber strands and strand end faces having determinable dimensions for conveyance and discharge of light energy;

preparing a fluid prepolymer reaction mixture composition comprising at least one photoinitiator and at least one chemical entity selected from the group consisting of monomers, dimers, oligomers, copolymers, and homopolymers that can be photocrosslinked to yield a photodeposited polymer product, said photoinitiator and said chemical entity being admixed at predetermined concentrations;

immersing a solid substrate surface in said fluid prepolymer mixture at a distance less than 50 micrometers from said discrete optic array end surfaces;

adjusting said light energy intensity, said wavelength, and said exposure time to said concentrations and said composition of said prepolymer mixture for precisely scaling and sizing the pattern of said three-dimensional polymer microstructure;

introducing said shaft of light energy to only a portion of said multiple optical fiber strand end faces forming one optic array end surface of said unitary optic array such that said introduced shaft of light energy becomes divided into a prearranged pattern of multiple beams of light energy which are individually conveyed through preselected ones of said multiple optical fiber strands of said unitary optic array and said conveyed multiple beams are discharged as a patterned template of configured light energy zones from the other optic array end surface of said unitary optic array, said discharged multiple individual beams of light energy having individual beam dimensions essentially equivalent to said determinable dimensions of said multiple optical fiber strands and strand end faces;

directing said multiple individual beams of light energy to said substrate surface;

depositing a cured polymer on said substrate surface by way of a photoinitiated polymerization reaction, whereby a three-dimensional and integral photodeposited polymer microstructure of prearranged pattern and precise scale is formed on said substrate surface, said integral polymer microstructure comprising a plurality of precisely scaled polymeric projections each having a breadth and shape essentially equivalent to said determinable dimensions of said multiple optical fiber strands; and

terminating the deposition of said cured polymer microstructure when the breadth of said polymeric projections is essentially equivalent to the dimension of said individual optical fiber strand end faces, wherein said fabricated polymer microstructure is an electroactive microelectrode.

2. A photo deposition method for fabricating a three-dimensional polymer microstructure of prearranged pattern and precise scale, said photo deposition method comprising the steps of:

furnishing at least one shaft of light energy of determinable wavelength, intensity, and exposure time;

providing a masking means for converting said shaft of light energy into a prechosen photopattern comprised of at least one light energy ray having a fixed configuration;

supplying a preformed, unitary fiber optic array comprising a plurality of clad optical fiber strands disposed co-axially along their lengths and having two discrete optic array end surfaces each formed of multiple optical fiber strand end faces, said preformed, unitary optic array being of determinable configuration and dimensions, and said discrete optic array end surfaces presenting multiple optical fiber strands and strand end faces having determinable dimensions for conveyance and discharge of light energy;

preparing a fluid prepolymer reaction mixture composition comprising at least one photoinitiator and at least one chemical entity selected from the group consisting of monomers, dimers, oligomers, copolymers, and homopolymers that can be photocrosslinked to yield a photodeposited polymer product, said photoinitiator and said chemical entity being admixed at predetermined concentrations;

immersing a solid substrate surface in said fluid prepolymer mixture at a distance less than 50 micrometers from said discrete optic array end surfaces;

adjusting said light energy intensity, said wavelength, and said exposure time to said concentrations and said composition of said prepolymer mixture for precisely scaling and sizing the pattern of said three-dimensional polymer microstructure;

introducing said photopatterned shaft of light energy to only a portion of said multiple optical fiber strand end faces forming one optic array end surface of said unitary optic array such that said introduced photopatterned shaft of light energy becomes divided into a prearranged pattern of multiple beams of light energy which are individually conveyed through preselected ones of said multiple optical fiber strands of said unitary optic array and said conveyed multiple beams are discharged as a patterned template of configured light energy zones from the other optic array end surface of said unitary optic array, said discharged multiple individual beams of light energy having, individual beam dimensions essentially equivalent to said determinable dimensions of said multiple optical fiber strands and strand end faces;

directing said multiple individual beams of light energy to said substrate surface;

depositing a cured polymer on said substrate surface by way of a photoinitiated polymerization reaction, whereby a three-dimensional and integral photodeposited polymer microstructure of prearranged pattern and precise scale is formed on said substrate surface, said integral polymer microstructure comprising a plurality of precisely scaled polymeric projections each having a breadth and shape essentially equivalent to said determinable dimensions of said multiple optical fiber strands; and

terminating the deposition of said cured polymer microstructure when the breadth of said polymeric projections is essentially equivalent to the dimension of said individual optical fiber strand end faces, wherein said fabricated polymer microstructure is an electroactive microelectrode.

3. A photodeposition method for fabricating a three-dimensional polymer microstructure of prearranged pattern and precise scale, said photo deposition method comprising the steps of:

furnishing at least one shaft of light energy of determinable wavelength, intensity, and exposure time;

supplying a preformed, unitary fiber optic array comprising a plurality of clad optical fiber strands disposed co-axially along their lengths and having two discrete optic array end surfaces each formed of multiple optical fiber strand end faces, said preformed, unitary optic array being of determinable configuration and dimensions, and said discrete optic array end surfaces presenting multiple optical fiber strands and strand end faces having determinable dimensions for conveyance and discharge of light energy;

preparing a fluid prepolymer reaction mixture composition comprising at least one photoinitiator and at least one chemical entity selected from the group consisting of monomers, dimers, oligomers, copolymers, and homopolymers that can be photocrosslinked to yield a photodeposited polymer product, said photoinitiator and said chemical entity being admixed at predetermined concentrations;

immersing a solid substrate surface in said fluid prepolymer mixture at a distance less than 50 micrometers from said discrete optic array end surfaces;

adjusting said light energy intensity, said wavelength, and said exposure time to said concentrations and said composition of said prepolymer mixture for precisely scaling and sizing the pattern of said three-dimensional polymer microstructure;

introducing said shaft of light energy to only a portion of said multiple optical fiber strand end faces forming one optic array end surface of said unitary optic array such that said introduced shaft of light energy becomes divided into a prearranged pattern of multiple beams of light energy which are individually conveyed through preselected ones of said multiple optical fiber strands of said unitary optic array and said conveyed multiple beams are discharged as a patterned template of configured light energy zones from the other optic array end surface of said unitary optic array, said discharged multiple individual beams of light energy having individual beam dimensions essentially equivalent to said determinable dimensions of said multiple optical fiber strands and strand end faces;

directing said multiple individual beams of light energy to said substrate surface;

depositing a cured polymer on said substrate surface by way of a photoinitiated polymerization reaction, whereby a three-dimensional and integral photodeposited polymer microstructure of prearranged pattern and precise scale is formed on said substrate surface, said integral polymer microstructure comprising a plurality of precisely scaled polymeric projections each having a breadth and shape essentially equivalent to said determinable dimensions of said multiple optical fiber strands;

terminating the deposition of said cured polymer microstructure when the breadth of said polymeric projections is essentially equivalent to the dimension of said individual optical fiber strand end faces; and

rinsing said substrate surface to remove uncured prepolymer fluid, wherein said solid substrate surface is a coverslip.