Abstract:
A method for manufacturing an ink jet printer head is disclosed which the method comprises steps of providing a substrate; forming a crater layer by photolighography and plating under the substrate; forming a nozzle plate by photolighography and plating under the crater layer; forming a channel plate by photolighography and plating under the nozzle plate; forming a reserver plate by photolighography and plating under the channel plate; forming a restrictor plate by photolighography and plating under the reserver plate; forming a chamber plate by photolighography and plating under the restrictor plate; forming a vibration plate by plating under the chamber plate; removing the substrate; removing all photoresist remaining; forming a piezoelectric/electrostrictive film to actuate when electrified upon the vibration plate; and forming an upper electrode upon the piezoelectric/electrostrictive film.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a printer head and particularly to a manufacturing method of an ink jet printer head. 
     2. Description of the Prior Art 
     Ink jet printer head is generally formed by sequential accumulation of nozzle plate  222  where nozzle  223  has been formed, reserver plate  221  where reserver  220  is formed, channel plate  219  where flow channel  218  is formed, restrictor plate  217  where restrictor  216  is formed, chamber plate  215  forming a chamber  214 , and actuator composed of three parts of upper electrode  210 , piezoelectric substance  211  and lower electrode  212  as in FIG.  1 . 
     Ink flowpath is formed in ink jet printer head by the above formation of such as nozzle  223 , reserver  220 , flow channel  218 , restrictor  216 , chamber  214  of mutually different sizes and shapes. 
     Ink supplied from ink canister (not shown in figure) is reserved in reserver  220  after which it flows into chamber  214  through flow channel  218  whence the reserver  220  formed between flow channel  218  and chamber  214  maintains ink flow speed into chamber  214  to a constant state. 
     Piezoelectric substance  211  is actuated if voltage is applied at upper electrode  210  and lower electrode  212  of actuator formed upon chamber  214 ; by which piezoelectric substance  211  actuation the chamber  214  volume momentarily decreases while chamber  214  ink is ejected through nozzle  223  formed at nozzle plate  222  onto material on which to be written. Printing is carried out by this ink jet. 
     Until now to manufacture an ink jet printer head as described above, use has been made of method of assembling after separately making a nozzle plate where nozzle is formed, a reserver plate where reserver is formed, a channel plate where channel is formed, a restrictor plate where restrictor is formed and a chamber plate where chamber is formed. 
     In this method, each plate comprising the ink jet printer head as above is manufactured by each separate process, and photoresist is coated on each of these separately manufactured plates which are then exposed to light, after which the guide holes are formed for assembling, by way of micro-patterning utilizing a micro-punching or a lithography process, then these plates are piled one upon another. Guide holes are fastened by screw etc. to fix the plates which are then thermally treated so that they are bonded together to finish the ink jet printer head. 
     In this traditional method, there is problem that yield percentage is low because there is large possibility to generate assembly tolerance error owing to inaccurate congruence of the guide hole positions and the plate sizes when assembling. And there is demerit of production cost rise because such photoresist should be used as is excellent in adhesion and low in reactivity with ink, which photoresist is to be coated before bonding the plates together. 
     SUMMARY OF THE INVENTION 
     Purpose of the present invention to solve the above problems is to provide a manufacturing method of ink jet printer head by forming the parts in a bundle using electrochemical process. 
     This invention to achieve the above purpose relates to a manufacturing method of an ink jet printer head comprising steps of providing a substrate; forming a first photoresist layer by coating photoresist in the thickness of a crater layer under the substrate; leaving the first photoresist only at crater part by patterning, exposing to light and etching the first photoresist layer; forming the crater layer under the substrate by plating process; forming a second photoresist layer by coating photoresist in the thickness of a nozzle plate under the crater layer; leaving the second photoresist only at nozzle part by patterning, exposing to light and etching the second photoresist layer; forming the nozzle plate under the crater layer by plating process; forming a third photoresist layer by coating photoresist in the thickness of a channel plate under the nozzle plate; leaving the third photoresist only at channel part by patterning, exposing to light and etching the third photoresist layer; forming the channel plate under the nozzle plate by plating process; forming a fourth photoresist layer by coating photoresist in the thickness of a reserver plate under the channel plate; leaving the fourth photoresist only at reserver part by patterning, exposing to light and etching the fourth photoresist layer; forming the reserver plate under the channel plate by plating process; forming a fifth photoresist layer by coating photoresist in the thickness of a restrictor plate under the reserver plate; leaving the fifth photoresist only at restrictor part by patterning, exposing and etching the fifth photoresist layer; forming the restrictor plate under the reserver plate by plating process; forming a sixth photoresist layer by coating photoresist in the thickness of a chamber plate under the restrictor plate; leaving the sixth photoresist only at chamber part by patterning, exposing and etching the sixth photoresist layer; forming the chamber plate under the restrictor plate by plating process; forming a vibration plate under the chamber plate by plating process; removing the substrate; removing all photoresist remaining; forming a piezoelectric/electrostrictive film to actuate when electrified upon the vibration plate; and forming an upper electrode upon the piezoelectric/electrostrictive film. 
     And this invention relates to a manufacturing method of an ink jet printer head comprising steps of providing a substrate made of piezoelectric/electrostrictive material; forming a vibration plate by plating under the substrate; forming a sixth photoresist layer by coating photoresist in the thickness of a chamber plate under the vibration plate; leaving the sixth photoresist only at chamber part by patterning, exposing and etching the sixth photoresist layer; forming the chamber plate by plating under the vibration plate; forming a fifth photoresist layer by coating photoresist in the thickness of a restrictor plate under the chamber plate; leaving the fifth photoresist only at restrictor part by patterning, exposing and etching the fifth photoresist layer; forming the restrictor plate by plating under the chamber plate; forming a fourth photoresist layer by coating photoresist in the thickness of a reserver plate under the restrictor plate; leaving the fourth photoresist only at reserver part by patterning, exposing to light and etching the fourth photoresist layer; forming the reserver plate by plating under the restrictor plate; forming a third photoresist layer by coating photoresist in the thickness of a channel plate under the reserver plate; leaving the third photoresist only at channel part by patterning, exposing to light and etching the third photoresist layer; forming the channel plate by plating under the reserver plate; forming a second photoresist layer by coating photoresist in the thickness of a nozzle plate under the channel plate; leaving the second photoresist only at nozzle part by patterning, exposing to light and etching the second photoresist layer; forming the nozzle plate by plating under the channel plate; forming a first photoresist layer by coating photoresist in the thickness of a crater layer under the nozzle plate; leaving the first photoresist only at crater part by patterning, exposing to light and etching the first photoresist layer; forming the crater layer by plating under the nozzle plate; removing all photoresist remaining; forming a piezoelectric/electrostrictive film by lapping, patterning and etching the substrate; and forming an upper electrode upon the piezoelectric/electrostrictive film. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a cross section view of general ink jet printer heads. 
     FIG.  2  through FIG. 26 represent flow diagrams showing an example of the present invention. 
     FIG.  27  through FIG. 50 represent flow diagrams showing another example of the present invention. 
    
    
     DETAILED DESCRIPTION 
     Silicon (Si) wafer, metals such as stainless steel, polymeric compounds, or ceramic materials such as aluminium oxide (Al 2 O 3 ), silicon dioxide (SiO 2 ) and PZT may be used for material of a substrate that is the base. 
     First photoresist is coated by the thickness of crater layer under the above substrate and then is exposed and etched so that part where crater is to be formed is shielded by the first photoresister. 
     Seeding layer must be formed under substrate in case where nonconductive ceramics, polymer or silicon wafer is used for substrate. The seeding layer may not be formed in case where metal is used for substrate but a separate seeding layer may be formed for plating to take place in stable condition. As for seeding layer, film is formed by evaporation or sputtering of conductive metal such as gold (Au) or nickel (Ni). 
     Crater layer is formed after shielding by first photoresister under metallic substrate or other substrate where seeding layer has been formed. 
     Second photoresist is coated by thickness of nozzle plate under formed crater layer and then is exposed and etched so that part where nozzle is to be formed is shielded by the second photoresister. Nozzle plate is formed under crater layer after shielding by second photoresister. 
     Third photoresist is coated by thickness of channel plate under formed nozzle plate and then is exposed and etched so that part where channel is to be formed is shielded by the third photoresister. Channel plate is formed under nozzle plate after shielding by third photoresister. 
     Fourth photoresist is coated by thickness of reserver plate under formed channel plate and then is exposed and etched so that part where reserver is to be formed is shielded by the fourth photoresister. Reserver is formed under channel plate after shielding by fourth photoresister. 
     Fifth photoresist is coated by thickness of restrictor plate under formed reserver plate and then is exposed and etched so that part where restrictor is to be formed is shielded by the fifth photoresister. Restrictor plate is formed under reserver plate after shielding by fifth photoresister. 
     Sixth photoresist is coated by thickness of chamber plate under formed restrictor plate and then is exposed and etched so that part where chamber is to be formed is shielded by the sixth photoresister. Chamber plate is formed under restrictor plate after shielding by sixth photoresister. 
     Vibration plate is formed under formed chamber plate. 
     Single metal, complex metal, ceramic or metal-ceramic complex may be selectively used for material of crater layer, nozzle plate, channel plate, reserver plate, restrictor plate, chamber plate and vibration plate. Single metal, complex metal, ceramic or metal-ceramic complex may be selectively used for vibration plate material. Nickel (Ni), copper (Cu) etc. are preferable in case of single metal. Alloy such as nickel-chromium (Ni—Cr) or nickel-cobalt-tungsten (Ni—Co—W) is preferable in case of complex metal. Silicon dioxide (SiO 2 ), silicon nitride (Si 3 N 4 ), aluminium oxide (Al 2 O 3 ), silicon carbide (SiC) etc. are preferable in case of ceramics. And nickel-ceramic mixture of nickel-aluminium oxide (Ni—Al 2 O 3 ), nickel-silicon dioxide (Ni—SiO 2 ), nickel-titanium dioxide (Ni—TiO 2 ) etc. or of nickel-silicon carbide (Ni—SiC), nickel-titanium carbide (Ni—TiC), nickel-tungsten carbide (Ni—WC) etc. are preferable in case of metal-ceramic complex. 
     Whence adequate stuff material shall be selectively used considering ink jet printer head rigidity, reactivity of ink and ink jet printer head material, part material surface characteristics, external resistivity of corrosion resistance etc., because completed ink jet printer head characteristics may vary according to property of stuff material used at this manufacturing time. 
     Particularly it is preferable to use metal-ceramic complex in case of vibration plate because this kind of materials is highly rigid and so has excellent frequency characteristics so that crosstalk according to high scale integration of ink jet printer head may be prevented. 
     Crater layer, nozzle plate, channel plate, reserver plate, restrictor plate, chamber plate and vibration plate are formed by coating the above material where electrolytic plating process and nonelectrolytic plating process may be used for the coating method. 
     Substrate is removed after completing the whole structure by forming the vibration plate. Photoresist is removed by etching after removing the substrate. Crater, nozzle, channel, reserver, restrictor, and chamber are formed by removing the photoresistor contained in whole structure. 
     The above process may be performed in reverse order. Individual processes in case of this reverse sequence processing are same for each as described above; whence vibration plate, chamber plate, restrictor plate, reserver plate, channel plate, nozzle plate and crater layer are sequentially formed under substrate which is removed thereafter and then substance is etched to remove photoresist. 
     Ink jet printer head is completed either by forming piezoelectric/electrostrictive film actuator and upper electrode or by forming lower electrode, piezoelectric/electrostrictive film and upper electrode upon vibration plate formed by either of the methods explained above. Generally used methods may be used in forming the actuator. 
     Substrate may be lapped, patterned and etched so as to be used as piezoelectric/electrostrictive film after whole structure is completed in case where piezoelectric/electrostrictive material of PZT etc. is used for substrate in the above reverse order method. Then ink jet printer head is completed by only forming the upper electrode in this case. 
     Because the present invention method as explained above molds the ink jet printer head in a bundle by electrochemical batch process, mass production of large area is facile, and lead time is reduced because there came no need of adfixing and assembling processes of each and all part materials as conventional. 
     And yield percentage of each part is enhanced, high precision array is feasible because arrangement error of molded structure substance is minimized, and rigidity and ink bearing characteristics of head parts such as hydrophilicity and water repellency may be controlled by properly selecting the composition elements of each part, which characteristics are required per position part respectively. 
     Now the present invention is explained again in detail referring to appended drawings. 
     FIG.  2  through FIG. 26 show an example of methods of the present invention. 
     First photoresist  12  is coated by thickness of crater layer under substrate  10 , then is exposed and etched and portion where crater is to be formed is shielded by first photoresister  12 . Then crater layer  14  is formed under substrate. 
     Second photoresist  16  is coated by thickness of nozzle plate under formed crater layer  14 , then is exposed and etched and portion where nozzle is to be formed is shielded by second photoresister  16 . Then nozzle plate  18  is formed under crater layer  14 . 
     Third photoresist  20  is coated by thickness of channel plate under formed nozzle plate  18 , then is exposed and etched and portion where channel is to be formed is shielded by third photoresister  20 . Then channel plate  22  is formed under nozzle plate  18  shielded by third photoresister  20 . 
     Fourth photoresist  24  is coated by thickness of reserver plate under formed channel plate  22 , then is exposed and etched and portion where reserver is to be formed is shielded by fourth photoresister  24 . Then reserver plate  26  is formed under channel plate  22  shielded by fourth photoresister  24 . 
     Fifth photoresist  28  is coated by thickness of restrictor plate under formed reserver plate  26 , then is exposed and etched and portion where restrictor is to be formed is shielded by fifth photoresister  28 . Then restrictor plate  30  is formed under reserver plate  26  shielded by fifth photoresister  28 . 
     Sixth photoresist  32  is coated by thickness of chamber plate under formed restrictor plate  30 , then is exposed and etched and portion where chamber is to be formed is shielded by sixth photoresister  32 . Then chamber plate  34  is formed under restrictor plate  30  shielded by sixth photoresister  32 . 
     Substrate  10  is removed after body structure completion by forming the vibration plate  36  under formed chamber plate  34 . Photoresists  12 ,  16 ,  20 ,  24 ,  28  and  32  are removed by etching after substrate  10  removal. Crater  13 , nozzle  17 , channel  21 , reserver  25 , restrictor  29  and chamber  33  are formed if photoresist contained in whole structure has been removed so that ink jet printer head body will be completed. 
     Ink jet printer head is completed by forming lower electrode  38 , piezoelectric/electrostrictive film  40  and upper electrode  42  upon vibration plate  36  in ink jet printer head. 
     FIG.  27  through FIG. 50 show another example of methods of the present invention. 
     First vibration plate  86  is formed by plating under substrate  60  made of piezoelectric/electrostrictive material. 
     Sixth photoresist  82  is coated by thickness of chamber plate under formed vibration plate  60 , then is exposed and etched and portion where chamber is to be formed is shielded by sixth photoresister  82 . Then chamber plate  84  is formed under vibration plate  86  shielded by sixth photoresister  82 . 
     Fifth photoresist  78  is coated by thickness of restrictor plate under formed chamber plate  84 , then is exposed and etched and portion where restrictor is to be formed is shielded by fifth photoresister  78 . Then restrictor plate  80  is formed under chamber plate  84  shielded by fifth photoresister  78 . 
     Fourth photoresist  74  is coated by thickness of reserver plate under formed restrictor plate  80 , then is exposed and etched and portion where reserver is to be formed is shielded by fourth photoresister  74 . Then reserver plate  76  is formed under restrictor plate  80  shielded by fourth photoresister  74 . 
     Third photoresist  70  is coated by thickness of channel plate under formed reserver plate  76 , then is exposed and etched and portion where channel is to be formed is shielded by third photoresister  70 . Then channel plate  72  is formed under reserver plate  76  shielded by third photoresister  70 . 
     Second photoresist  66  is coated by thickness of nozzle plate under formed channel plate  72 , then is exposed and etched and portion where nozzle is to be formed is shielded by second photoresister  66 . Then nozzle plate  68  is formed under channel plate  72  shielded by second photoresister  66 . 
     First photoresist  62  is coated by thickness of crater layer under formed nozzle plate  68 , then is exposed and etched and portion where crater is to be formed is shielded by first photoresister  62 . Then crater layer  64  is formed under nozzle plate  68  shielded by first photoresister  62 . 
     Photoresists  62 ,  66 ,  70 ,  74 ,  78  and  82  are removed by etching after body structure completion by forming the crater layer  64 . Crater  63 , nozzle  67 , channel  71 , reserver  75 , restrictor  79  and chamber  83  are formed if photoresists have been removed so that ink jet printer head body will be completed. 
     Piezoelectric/electrostrictive film  90  is formed by etching the substrate  60  after lapping to a definite thickness after completing the body structure. Ink jet printer head is completed by forming upper electrode  92  upon formed piezoelectric/electrostrictive film  90 .