Embodiment
Can know by background technology; Bottom anti-reflection layer is applied to improving in the photoetching precision of photoetching; Prior art forms the common meeting of photoresist figure and forms bottom anti-reflection layer at substrate surface, forms photoresist layer at said bottom anti-reflective laminar surface, to said photoresist layer exposure, development; Form the photoresist figure, but the photoresist figure that prior art forms has a large amount of defectives usually.
Inventor of the present invention finds that through the research back reason that said defective forms is specially: bottom anti-reflection layer is organism normally, and the bottom anti-reflection layer that is formed on substrate surface is generally slant acidity; Though semiconductor technology can be under the environment of ultra-clean, to carry out usually, the environment of said ultra-clean can not be a vacuum environment yet, can have the molecule of meta-alkalescence usually in the environment of ultra-clean, for example has OH
-The molecule of ionic group etc.The substrate that is formed with bottom anti-reflection layer is in the environment of the molecule that has meta-alkalescence; The molecule that is easy to just adsorb meta-alkalescence is at the bottom anti-reflective laminar surface; In subsequent technique; Form photoresist at the said bottom anti-reflective laminar surface that is formed with the molecule of absorption meta-alkalescence, defective will appear in the position of the molecule of said absorption meta-alkalescence.
For this reason, people inventor of the present invention proposes a kind of formation method of photoresist, and concrete steps comprise:
The substrate that is formed with bottom anti-reflection layer is provided;
Remove the meta-alkalescence molecule in the said bottom anti-reflection layer;
Bottom anti-reflective laminar surface at the molecule of removing meta-alkalescence forms photoresist layer.
Optional, the meta-alkalescence in the said bottom anti-reflection layer of said removal divides substep and said bottom anti-reflective laminar surface at the molecule of removing meta-alkalescence to form the photoresist layer step to accomplish same revolving in the gluing equipment.
Optional, the meta-alkalescence molecule of removing in the said bottom anti-reflection layer comprises: the said substrate that is formed with bottom anti-reflection layer is positioned over said revolving in the gluing equipment; Revolve the gluing equipment initialization; The molecule of meta-alkalescence is removed in cleaning and rotation; Dry.
Optional, the said concrete technological parameter of gluing equipment initialization that revolves is: rotational time is 1 second to 2 seconds, rotational speed is for changeing (RPM) to per minute 2500 commentaries on classics for per minute 1500.
Optional, said cleaning and rotation go the concrete technological parameter of the molecule of meta-alkalescence to be: rotational time is 3 seconds to 5 seconds, revolves the gluing equipment rotational speed and is per minute 80 and go to per minute 120 and change, and the clean-out system flow is that 30 milliliters of per minutes are to 80 milliliters of per minutes.
Optional, said clean-out system can be macromolecule organic solvent, deionized water or oxydol.
Optional, the concrete technological parameter of said drying is: rotational time is 3 seconds to 9 seconds, the said gluing equipment rotating speed that revolves is that per minute 800 goes to per minute 2500 commentaries on classics.
Optional, the concrete technological parameter of said formation photoresist is: rotational time is 1 second to 2 seconds, revolves the gluing equipment rotating speed and is per minute 3400 and go to per minute 4000 and change, and the photoresist flow is that 1.5 milliliters of per minutes are to 2 milliliters of per minutes.
For make above-mentioned purpose of the present invention, feature and advantage can be more obviously understandable, does detailed explanation below in conjunction with the accompanying drawing specific embodiments of the invention.A lot of details have been set forth in the following description so that make much of the present invention.But the present invention can implement much to be different from alternate manner described here, and those skilled in the art can do similar popularization under the situation of intension of the present invention, so the present invention does not receive the restriction of following disclosed practical implementation.
Secondly, the present invention utilizes synoptic diagram to be described in detail, when the embodiment of the invention is detailed; For ease of explanation; The sectional view of expression device architecture can be disobeyed general ratio and done local the amplification, and said synoptic diagram is instance, and it should not limit the scope of the present invention's protection at this.The three dimensions size that in actual fabrication, should comprise in addition, length, width and the degree of depth.
Fig. 1 is the process flow diagram of the formation method of photoresist of the present invention, describes with reference to figure 1 below.
As shown in Figure 1, the formation method of photoresist of the present invention comprises the following steps:
Step S101 provides the substrate that is formed with bottom anti-reflection layer.
With reference to figure 2, substrate 100 is provided.
Said substrate 100 can be substrate (part that comprises integrated circuit and other elements), the patterning of multi layer substrate (silicon substrate that for example, has covering dielectric and metal film), classification substrate, silicon-on-insulator substrate (SOI), epitaxial silicon substrate, section processes or the substrate that is not patterned.
Said substrate 100 can also be the substrate with dielectric layer; Said dielectric layer is used for lead on the substrate and the isolation between the lead; Concrete said dielectric layer can be before-metal medium layer (Pre-MetalDielectric; PMD), also can be interlayer dielectric layer (Inter-Metal Dielectric, ILD).
Before-metal medium layer is to be deposited on the substrate with MOS device; Utilize depositing operation to form; In before-metal medium layer, can form groove at subsequent technique, form connecting hole with metal filled groove, said connecting hole is used for connecting the electrode of MOS device and the plain conductor of upper layer interconnects layer.
Interlayer dielectric layer is the dielectric layer of postchannel process between metal interconnecting layer, can in subsequent technique, form groove in the interlayer dielectric layer, forms connecting hole with metal filled groove, and said connecting hole is used for connecting the lead of adjacent metal interconnects layer.
The material of said dielectric layer is selected from SiO usually
2The SiO that perhaps mixes
2USG (UndopedSilicon Glass for example; The silex glass that does not have doping), BPSG (Borophosphosilicate Glass; The silex glass of boron phosphorus doped), BSG (Borosilicate Glass, the silex glass of doped with boron), PSG (Phosphosilitcate Glass, the silex glass of Doping Phosphorus) etc.
Said dielectric layer generally selects for use the dielectric material of low-k, the material of said dielectric layer specifically to be selected from the silit (BLOK) that monox (BlackDiamond) that fluorine silex glass (FSG), carbon mix and nitrogen mix at 130 nanometers and following process node.
The formation technology of said dielectric layer can be any conventional vacuum coating technology, and for example atomic deposition (ALD), physical vapor deposition (PVD), chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD) or the like are not here done and given unnecessary details.
With reference to figure 3, form bottom anti-reflection layer 110 on said substrate 100 surfaces.
Said bottom anti-reflection layer 110 is used to prevent reflect at the wafer interface after light is through the photoresist of follow-up formation, makes to improve the precision of exposure by the photoresist uniform exposure.
Said bottom anti-reflection layer 110 materials are the compound of C-H-O, and the technology that forms bottom anti-reflection layer 130 can be spin coating proceeding.
Existing processes can be after forming bottom anti-reflection layer 110; Form photoresist layer on said bottom anti-reflection layer 110 surfaces; Because bottom anti-reflection layer 110 materials that existing processes forms are generally the organism of the compound of C-H-O; The bottom anti-reflection layer 110 that forms is slant acidity normally, and the said bottom anti-reflection layer 110 that is formed on substrate 100 is easy to adsorb the molecule of meta-alkalescence, in follow-up formation photoresist process; At the photoresist that the said bottom anti-reflective laminar surface that is formed with the molecule of absorption meta-alkalescence forms, defective will appear in the position of the molecule of said absorption meta-alkalescence.
For this reason, the photoresist layer that inventor of the present invention proposes a kind of advanced person forms technology, and is of step S102 and step S103, removes the meta-alkalescence molecule in the said bottom anti-reflection layer 110; Bottom anti-reflection layer 110 surfaces at the molecule of removing meta-alkalescence form photoresist layer.
What need particularly point out is; The meta-alkalescence of removing in the said bottom anti-reflection layer 110 divides substep and forms the photoresist layer step on bottom anti-reflection layer 110 surfaces of the molecule of removing meta-alkalescence and can in same equipment, accomplish; And can be integrated in the same technology preparation, practiced thrift the processing step time.
The meta-alkalescence of removing in the said bottom anti-reflection layer 110 divides substep in revolving gluing equipment, to accomplish, and the said branch substep of meta-alkalescence that goes specifically comprises: the said substrate 100 that is formed with bottom anti-reflection layer 110 is positioned over said revolving in the gluing equipment; Revolve the gluing equipment initialization; The molecule of meta-alkalescence is removed in cleaning and rotation; Dry.
The said concrete parameter of gluing equipment initialization of revolving is: rotational time is 1 second to 2 seconds, and rotational speed is for changeing (RPM) to per minute 2500 commentaries on classics for per minute 1500.
Said cleaning and rotation go the concrete parameter of the molecule of meta-alkalescence to be: rotational time is 3 seconds to 5 seconds; Revolving the gluing equipment rotational speed is that per minute 80 goes to per minute 120 commentaries on classics; The clean-out system flow be 30 milliliters of per minutes to 80 milliliters of per minutes, said clean-out system can be macromolecule organic solvent, deionized water or oxydol.
What need particularly point out is, inventor of the present invention is through a large amount of experiments, finds that said clean-out system selects propylene glycol first monoether (molecular formula: CH for use
3OCH
2CH (OH) CH
3) or select propylene glycol monomethyl ether ethyl ester (molecular formula: CH3CH (OCOCH for use
3) CH
2OCH
3) time, the effect of the molecule of removal meta-alkalescence is better.
The concrete parameter of said drying step is: rotational time is 3 seconds to 9 seconds, and the said gluing equipment rotating speed that revolves is that per minute 800 goes to per minute 2500 commentaries on classics.
Adopt the branch substep that removes meta-alkalescence of above-mentioned parameter can effectively remove molecule, and can not damage bottom anti-reflection layer 110 attached to the meta-alkalescence of bottom anti-reflective laminar surface.
With reference to figure 4, form photoresist layer 120 on bottom anti-reflection layer 110 surfaces of the molecule of removing meta-alkalescence
Said formation photoresist layer 120 technologies can be selected for use and revolve gluing equipment; Inventor of the present invention is through a large amount of creative works; Obtain more excellent photoresist and form technological parameter: select for use and revolve gluing equipment; Rotational time is 1 second to 2 seconds, and revolving the gluing equipment rotating speed is 0, and macromolecule organic solvent flow velocity is that 30 milliliters of per minutes are to 80 milliliters of per minutes; This step is used to remove other impurity of bottom anti-reflective laminar surface.
Rotational time is 1 second to 2 seconds, and revolving the gluing equipment rotating speed is 0, and macromolecule organic solvent flow velocity is 0; This step is used to remove the macromolecule organic solvent.
Rotational time is 0.1 second to 0.22 second, and revolving the gluing equipment rotating speed is that per minute 800 goes to per minute 1000 commentaries on classics; This step is used to remove the hydrone of bottom anti-reflection layer 110 surface adsorption.
Rotational time is 1 second to 2 seconds, revolves the gluing equipment rotating speed and is per minute 3400 and go to per minute 4000 and change, and the photoresist flow is that 1.5 milliliters of per minutes are to 2 milliliters of per minutes; This step is used for forming said photoresist layer 120 on bottom anti-reflection layer 110 surface, and controls said photoresist layer 120 thickness, makes said photoresist layer 120 according with process requirements in follow-up exposure, development, formation photoresist graphics art.
Rotational time is 5 seconds to 25 seconds, and revolving the gluing equipment rotating speed is that per minute 1000 goes to per minute 1500 commentaries on classics; This step is used to remove the hydrone that is formed on the photoresist surface.
Rotational time is 2 seconds to 8 seconds, revolves the gluing equipment rotating speed and is per minute 1000 and go to per minute 2000 and change, and the detersive flow is that 30 milliliters of per minutes are to 80 milliliters of per minutes; This step is used to remove the photoresist that is formed on edges of substrate and substrate bottom.
Rotational time is 2 seconds to 6 seconds, and revolving the gluing equipment rotating speed is that per minute 1500 goes to per minute 2500 commentaries on classics; This step is used to dry said photoresist layer 120.
The present invention is through removing the branch substep of meta-alkalescence to said bottom anti-reflection layer; Form photoresist layer at the said bottom anti-reflective laminar surface of the molecule of meta-alkalescence that goes, reduced the defective that is formed on lithography layer, improved the yield of follow-up formation photoresist figure.