JP2010086840A - Patterning method, and device manufacturing method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a patterning method capable of enlarging a device and highly precisely forming a fine pattern without deteriorating characteristics of a thin film including an organic EL material, and to provide a device manufacturing method using the patterning method. <P>SOLUTION: A photothermal conversion layer and a partition pattern are formed on a substrate, a donor substrate in which a transfer material exists is disposed face to face with a device substrate in the partition pattern, light having a width wider than the sum of each width of m (m is 2 or larger integers) transfer materials and the width of the partition pattern existing between these transfer materials is emitted to the photothermal conversion layer a plurality of times separately. Accordingly, the m transfer materials are collectively transferred to the device substrate, and at least one transfer material among the m transfer material is transferred in the thickness direction n times (n is 2 or larger integers) separately. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for patterning a thin film constituting a device such as an organic EL element, an organic TFT, a photoelectric conversion element, and various sensors, and a method for manufacturing a device using the patterning method.

  In the organic EL element, electrons injected from a cathode and holes injected from an anode are recombined in an organic light emitting layer sandwiched between both electrodes. Kodak's C.I. W. Since Tang et al. Showed that organic EL elements emit light with high brightness (see Non-Patent Document 1), many research institutions have studied thin display and surface illumination devices as targets. .

  This light-emitting element has a characteristic that is thin and has high brightness emission under a low driving voltage, which is not found in other thin displays. By using various organic materials for the light-emitting layer, red (R), green (G) Since various emission colors such as the three primary colors of blue (B) can be obtained, practical use as a color display is progressing.

  FIG. 1 shows the structure of an active matrix color display, which is one of the typical structures of current organic EL displays. In order to have excellent characteristics as an organic EL display, it is required that at least the light emitting layers 17R, 17G, and 17B have uniform light emission and the light emission intensity does not change for a long time.

  For this purpose, the thickness of the light emitting layer is uniform, the purity of the organic material forming the light emitting layer is extremely high, and a fine pattern with a high purity and a uniform thickness is accurately formed on the substrate. Is required. Furthermore, in order to realize a high-performance organic EL device, a multilayer structure is required, and a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron having a typical film thickness of 0.1 μm or less It is necessary to sequentially stack an injection layer and the like.

  Conventionally, wet processes such as a photolithography method, an inkjet method, and a printing method have been used for fine patterning of a thin film. However, in the wet process, it is difficult to completely prevent changes in the shape or undesirable mixing of the extremely thin underlayer when applying photoresist or ink on the previously formed underlayer. The materials that can be used are limited. In addition, it is difficult to achieve film thickness uniformity within a pixel of a thin film formed by drying from a solution and between pixels within a substrate, and current concentration and element deterioration due to film thickness unevenness occur. In addition, there is a problem that the performance as a display is lowered.

  As a patterning method by a dry process that does not use a wet process, a mask vapor deposition method has been studied. The light emitting layer of a small organic EL display which is actually put into practical use is exclusively patterned by this method. However, the vapor deposition mask used for patterning by the mask vapor deposition method needs to open a precise pattern on the metal plate to be used in order to form a fine pattern on the substrate with high accuracy. It is difficult to achieve compatibility, and the larger the size, the more the adhesion between the substrate and the vapor deposition mask tends to be impaired. Therefore, application to a large organic EL display is difficult.

  In order to realize an increase in size by a dry process, the organic EL material on the donor film is patterned in advance, and the entire donor film is heated while the device substrate and the organic EL material on the donor film are in close contact with each other. A method of transferring an organic EL material is disclosed (see Patent Document 1). Further, the organic EL material patterned in the partition pattern (partition wall) is opposed to the device substrate so as not to contact the device substrate, and the donor substrate is heated by a hot plate to evaporate the organic EL material and deposit it on the device substrate. A transfer method is disclosed (see Patent Document 2). However, in the above method, since the entire donor substrate is heated and thermally expanded, the relative position of the organic EL material patterned on the donor substrate with respect to the device substrate is displaced, and the amount of displacement increases as the size increases. There was a problem that high-precision patterning was difficult. Furthermore, there is a problem that the device performance deteriorates because the device substrate opposed at a short distance is heated by radiation or has a partition pattern, which is affected by degassing from the partition pattern. It was.

  As a method of preventing displacement due to thermal expansion of the donor substrate, a photothermal conversion layer is formed on the donor substrate, an organic EL material is formed on the entire surface by thermal evaporation, and the photothermal conversion layer is partially irradiated with a high-intensity laser. To selectively transfer a portion of the organic EL material formed on the entire surface or separately coated with R, G, and B without using a partition pattern to the device substrate by heating and heating only the photothermal conversion layer A method has been developed (see Patent Documents 3 to 4). However, since the generated heat is also diffused in the lateral direction, the organic EL material in a region wider than the laser irradiation range is transferred, and the boundary is not clear. In order to prevent this, it is conceivable to irradiate a high-intensity laser in an extremely short time. However, in this case, since the organic EL material is heated to a high temperature in an extremely short time, it is difficult to accurately control the maximum temperature. Therefore, there is a problem that the probability that the organic EL material reaches the decomposition temperature or higher is increased, and as a result, the device performance is deteriorated.

As another method for preventing displacement due to thermal expansion of the donor substrate, a direct heating transfer method is disclosed in which the organic EL material on the donor substrate is directly heated with a laser without forming a photothermal conversion layer on the donor substrate (patent). Reference 5). In Patent Document 5, the possibility of color mixing at the time of patterning is further reduced by separately coating R, G, and B with partition patterns. However, since the typical film thickness of the organic EL material is very thin at 25 nm, there is a problem that the laser reaches the device substrate without being sufficiently absorbed and heats the underlying layer on the device substrate. A high-intensity laser is required to perform sufficient transfer. However, since the partition pattern deteriorates when the partition pattern is irradiated with the laser, only the organic EL material is irradiated with the laser to prevent the deterioration. However, there is a problem that high-precision positioning is required and it is difficult to increase the size.
“Applied Physics Letters” (USA), 1987, 51, 12, 913-915. JP 2002-260854 A JP 2000-195665 A Japanese Patent No. 3789991 JP 2005-149823 A JP 2004-87143 A

  As described above, in the conventional transfer technique, in order to accurately transfer the organic EL material having a desired pattern size, it is necessary to prevent heat conduction in the lateral direction as much as possible. It is indispensable to irradiate each pixel for a short time, and it has been difficult to stably realize fine patterning without damaging the organic EL material while maintaining high productivity with a large substrate.

  The present invention solves such problems, and enables a patterning method that enables large-scale and high-precision fine patterning while maintaining high productivity without deteriorating the characteristics of thin films including organic EL materials, and It is an object to provide a method of manufacturing a device that uses such a patterning method.

  The present invention has been made by earnestly researching so as to solve the conventional problems even if a light transfer method is used using a donor substrate having a partition pattern that may have adverse effects such as degassing. It is.

  That is, according to the present invention, a photothermal conversion layer and a partition pattern are formed on a substrate, and a donor substrate having a transfer material in the partition pattern is arranged to face the device substrate, and m (m is an integer of 2 or more). By irradiating the light-to-heat conversion layer in multiple times with light having a width wider than the total of the widths of the transfer materials and the widths of the partition patterns existing between the transfer materials, the m transfer materials And transferring at least one transfer material out of the m transfer materials divided in n times (n is an integer of 2 or more) in the film thickness direction. Patterning method.

  The present invention brings about a remarkable effect of enabling large-scale and high-precision fine patterning while maintaining high productivity without damaging a thin film including an organic EL material.

  2 and 3 are a cross-sectional view and a plan view showing an example of the thin film patterning method of the present invention. It should be noted that many figures used in this specification are described by extracting the minimum unit of RGB sub-pixels constituting a large number of pixels in a color display. In order to help understanding, the magnification in the vertical direction (substrate vertical direction) is increased as compared with the horizontal direction (substrate in-plane direction).

  In FIG. 2, the donor substrate 30 includes a support 31, a photothermal conversion layer 33, a partition pattern 34, and a transfer material 37 (coating film of RGB light emitting materials of organic EL) present in the partition pattern. A plurality of transfer materials 37R, 37G, and 37B are arranged side by side to form subpixels. The organic EL element (device substrate) 10 includes a support 11, a TFT (including extraction electrode) 12 formed thereon, a planarization film 13, an insulating layer 14, a first electrode 15, and a hole transport layer 16. In addition, since these are illustrations, the structure of each board | substrate is not limited to these as mentioned later. In a state where the partition pattern 34 of the donor substrate 30 and the insulating layer 14 of the device substrate 10 are aligned, the two substrates are arranged to face each other.

  Light (a laser is illustrated in the figure) is incident from the support 31 side of the donor substrate 30 and is absorbed by the photothermal conversion layer 33, and the transfer materials 37R, 37G, and 37B are simultaneously heated and evaporated by the heat generated there. By depositing on the hole transport layer 16 of the device substrate 10, the light emitting layers 17R, 17G, and 17B are collectively transferred. Laser irradiation is performed so that the entire region of the partition pattern 34 sandwiched between the transfer materials 37R, 37G, and 37B and a partial region of the partition pattern 34 positioned outside the transfer materials 37R and 37B are heated simultaneously with the transfer material 37. . At this time, at least one transfer material of the transfer materials 37R, 37G, and 37B remains without transferring all the film thickness at once, and the remaining transfer is completed by the second and subsequent irradiations. It is a feature of the present invention that the transfer is divided n times in the direction (n is an integer of 2 or more).

  In the present invention, since not all film thicknesses are transferred at one time, for example, when the laser irradiation time is the same, the transfer material can be transferred at a lower evaporation rate. This means that the intensity of light used is small and the transfer temperature is lower, so that the load on the transfer material is small and thermal degradation can be suppressed. Because the light intensity is small, even if the transfer material and the partition pattern are heated so that they are heated at the same time, the device performance may be adversely affected by separation of the partition pattern or degassing of the partition pattern. It can be minimized.

  In the present invention, a partition pattern corresponding to the device substrate is accurately drawn on the donor substrate, a transfer material is prepared in the accurately drawn partition pattern, and the donor substrate is aligned with the device substrate. Arrange. This makes it possible to accurately align the corresponding subpixels of the donor substrate and the device substrate. This eliminates the need to consider color mixing and impurity contamination due to the spread of heat to the side, and it is possible to transfer the transfer material to the device substrate by irradiating for a long time instead of the short-time irradiation previously used for transfer. It becomes. Since the transfer material can be transferred at a lower evaporation rate, the light intensity can be further reduced, the load on the transfer material can be further reduced, and thermal degradation can be suppressed synergistically.

  Further, in the conventional method in which only the transfer portion is irradiated with light, as shown in FIG. In the present invention, the transfer material existing at the boundary can be sufficiently heated and transferred. Therefore, since the film thickness distribution of the transfer thin film is made more uniform than before, adverse effects on device performance can be prevented.

  In the conventional method in which only the transfer material corresponding to one pixel is partially transferred, the effect of suppressing the material deterioration can be obtained even if the transfer is divided n times in the film thickness direction, but the processing per substrate is obtained. Since the time is approximately n times, there is a problem that productivity is greatly reduced. However, according to the present invention, m (m is an integer of 2 or more) transfer materials are collectively transferred, so that productivity can be maintained. In particular, it is preferable to use wide light that satisfies the condition of m ≧ n because high productivity equal to or higher than that of the conventional method can be secured.

  It is not uncommon for the transfer materials 37R, 37G, and 37B to have different evaporation rate temperature characteristics. Therefore, for example, as shown in FIG. 5, when the wide uniform light is irradiated, the transfer material 37B is transferred with the entire film thickness by the first irradiation, but 37R and 37G are transferred with half the film thickness. The remaining transfer of 37R and 37G can be completed by the second irradiation. Even if the transfer material 37B does not exist on the donor substrate 30 after the first irradiation, the second irradiation can be performed in the same arrangement as the first irradiation. In the same way, for example, 37R can be transferred 10 times, 37G 7 times, 37B 5 times, and the like. It is also possible to use a donor substrate on which only the transfer material 37B is not formed and only 37R and 37G are formed.

  When the transfer materials 37R, 37G, and 37B are light emitting materials for an organic EL element, the transfer material is a mixture of a host material and a dopant material as described later, and they have temperature characteristics with different evaporation rates. Is not uncommon. For example, when the evaporation temperature of the dopant material is lower than that of the host material, a phenomenon in which all of the dopant material evaporates first when heated at a low temperature for a long time. A phenomenon called flash evaporation, in which the material and the dopant material evaporate at substantially the same ratio, can be used. In the present invention, since it is possible to control not only the light irradiation time and the light irradiation intensity but also the number of times of transfer, it is relatively easy to find an appropriate high-speed evaporation condition equivalent to flash evaporation while suppressing material deterioration. It is possible to realize transfer in which the ratio of the host material and the dopant material does not change before and after the transfer.

  Further, according to the present invention, since light is sufficiently absorbed by the light-to-heat conversion layer, each RGB light emitting layer having a different light absorption spectrum can be heated to the same temperature using the same light source, There is no concern that the device substrate is heated by the transmitted light. Since the partition pattern exists, adjacent different transfer materials can be mixed and transfer of a portion where the boundary position fluctuates can be eliminated, so that device performance is not impaired even if batch transfer is performed. In addition, since the partition pattern can be patterned with high accuracy by a photolithography method or the like, a gap between transfer patterns of different transfer materials can be minimized. This leads to an effect that an organic EL display having a higher aperture ratio and excellent durability can be produced.

  Furthermore, as one of the preferred embodiments of the present invention, when the thickness of the partition pattern is made thicker than the transfer material, the temperature of the portion of the partition pattern that is thicker than the transfer material is further suppressed, and the temperature through the partition pattern is suppressed. Deterioration of the device substrate due to the rise can be suppressed to a problem-free level.

  By irradiating weak light for a long time, the light-to-heat conversion layer is heated to a substantially uniform temperature, and the temperature unevenness in each of the RGB light emitting layers is minimized, thereby forming the transferred pixel thickness uniformly. It becomes possible. Further, each RGB light emitting layer has a different light absorption spectrum and a different transfer speed, but the film thickness difference between the light emitting layers can be suppressed to a level with no problem.

  Since the partition pattern exists, adjacent different transfer materials can be mixed and transfer of a portion where the boundary position fluctuates can be eliminated, so that device performance is not impaired even if batch transfer is performed. In addition, since the partition pattern can be patterned with high accuracy by a photolithography method or the like, a gap between transfer patterns of different transfer materials can be minimized. This leads to an effect that an organic EL display having a higher aperture ratio and excellent durability can be produced.

  In the following, the present invention will be described in more detail.

(1) Irradiation light In the present invention, if a material and light irradiation conditions are selected, an ablation mode in which the transfer material 37 reaches the support 21 of the device substrate 20 in a state where the film shape is maintained can be used. From the viewpoint of reducing damage to the film, it is preferable to use a vapor deposition mode in which the transfer material 37 evaporates in a state of being loosened by 1 to 100 units of molecules (atoms) and transferred.

  In the present invention, since the damage to the transfer material is reduced, the damage to the partition pattern is also reduced at the same time, and even if the partition pattern is formed of an organic material, the deterioration hardly occurs. Therefore, the cost required for patterning can be reduced because the donor substrate can be reused a plurality of times. In addition, since it is not necessary to strictly control the absolute position of light irradiation and the relative position of the first and second light irradiation, the mechanism of the light irradiation apparatus can be simplified.

  As a light source of the irradiation light, a laser that can easily control the irradiation intensity and excellent in the shape control of the irradiation light can be exemplified as a preferable light source, but a light source such as an infrared lamp, a tungsten lamp, a halogen lamp, a xenon lamp, a flash lamp is used. You can also As the laser, a known laser such as a semiconductor laser, a fiber laser, a YAG laser, an argon laser, a nitrogen laser, or an excimer laser can be used. Since one of the objects in the present invention is to reduce damage to the transfer material, the continuous wave mode (CW) laser is more suitable than the intermittent oscillation mode (pulse) laser irradiated with high intensity light in a short time. Is preferred.

  The wavelength of the irradiation light is not particularly limited as long as the absorption in the irradiation atmosphere and the support of the donor substrate is small and it is efficiently absorbed in the photothermal conversion layer. Therefore, not only visible light region but also ultraviolet light to infrared light can be used. Considering a suitable support material for the donor substrate, 300 nm to 5 μm can be exemplified as a preferable wavelength region, and 380 nm to 2 μm can be illustrated as a more preferable wavelength region.

  The shape of irradiation light is not limited to the rectangle illustrated above. The optimum shape can be selected according to the transfer conditions such as linear, elliptical, square, polygonal. Irradiation light may be formed by superposition from a plurality of light sources, or conversely, a single light source may be divided into a plurality of irradiation lights. In an organic EL element or the like, since pixels are usually arranged in a rectangle, it is preferable that the irradiation light has a rectangular shape from the viewpoint of performing transfer without unevenness.

  In order to transfer all the transfer materials existing in the transfer region, it is necessary to irradiate the entire region by dividing it in a plurality of times in the film thickness direction. The irradiation method at this time is preferably scanning irradiation in order to reduce damage to the transfer material. As a scanning method, it may be possible to repeat an operation in which light having a width that can irradiate m transfer materials is repeatedly scanned and irradiated n times for a certain area and then moved to the next area, or An operation may be repeated n times, in which the light is first scanned and irradiated once over the entire transfer region, and the second scanning irradiation is performed after all of the scanning is completed. At this time, the number of repetitions need not be n over the entire transfer region, and regions with different numbers of scans may be mixed. Further, when scanning in the y direction as shown in FIG. 3, when the scan in the y direction is completed and the region moves to an adjacent region in the x direction, the irradiated region overlaps with the already irradiated region. May be. On the contrary, the partition pattern only needs to be able to irradiate firmly even in the vicinity where it is in contact with the transfer material. Therefore, for example, a region that is not irradiated near the center on the partition pattern may be generated. Therefore, alignment of light irradiation can be greatly reduced.

  Further, as shown in FIG. 6A, by irradiating light that covers the entire width of the transfer region 38 of the donor substrate 30, all transfer materials can be collectively transferred by a plurality of scans. With this arrangement, alignment of light irradiation with respect to the donor substrate 30 can be greatly reduced. As shown in FIG. 6B, when there are a plurality of transfer regions 38 on the substrate, it is also possible to transfer them all at once by a plurality of scans.

  The scanning speed is not particularly limited, but a range of 0.01 to 2 m / s is generally used. In the present invention, one of the purposes is to reduce damage to the transfer material by scanning at a lower speed under the condition that the energy density of light irradiation is relatively small. From this viewpoint, the scan speed is It is preferably 0.6 m / s or less, more preferably 0.3 m / s or less.

It is difficult to exemplify the preferable range of the intensity of irradiation light and the heating temperature of the transfer material. These are various such as uniformity of irradiation light, irradiation time (scanning speed), material and thickness of donor substrate support and photothermal conversion layer, reflectance, material and shape of partition pattern, material and thickness of transfer material, etc. This is because it depends on various conditions. A typical value of the energy density absorbed in the photothermal conversion layer is a range of 0.01 to 10 J / cm ² , and a heating temperature of the transfer material is a range of 220 to 400 ° C.

  FIG. 7 is a conceptual diagram showing the temperature change of the transfer material (or photothermal conversion layer) when light is irradiated for a certain period of time. Since it depends on various conditions, it cannot be generally stated, but as shown in Fig. 7 (a), the temperature gradually increases when the irradiation intensity (power density) is constant and rises even after reaching the target (evaporation temperature). Tend to. Even under these conditions, transfer can be performed without any problem depending on the thickness, heat resistance, and irradiation time of the transfer material. On the other hand, as a preferable irradiation method for further reducing the damage to the transfer material, as shown in FIG. 7B, the intensity is distributed so that the temperature becomes constant near the target and the period becomes longer. There is an example in which the irradiation intensity at a certain point is changed with time using irradiation light. Since the ability to reduce the damage to the transfer material means that the damage to the partition pattern can be reduced at the same time, for example, even when the partition pattern is formed using a photosensitive organic material, the partition pattern does not deteriorate and the donor pattern is not deteriorated. The number of times the substrate is reused can be increased.

  FIG. 8 is a perspective view showing a method of forming irradiation light. As shown in FIG. 8A, rectangular irradiation light can be cut out from a circular light beam by the optical mask 41. In addition to the optical mask 41, a knife edge or an optical interference pattern may be used. As shown in FIGS. 8B and 8C, the irradiation light can be formed by condensing or expanding the light from the light source 44 by the lens 42 and the mirror 43. In addition, by appropriately combining the optical mask 41, the lens 42, the mirror 43, etc., the irradiation light can be formed into an arbitrary shape. For example, the long axis direction of the rectangular irradiation light has a uniform irradiation intensity. However, it can also be designed to have a Gaussian distribution in the minor axis direction.

  FIG. 8D shows an example for realizing the time dependency of the irradiation intensity shown in FIG. The irradiation light is condensed obliquely through the lens 42 with respect to the surface of the donor substrate 30. If the near side of the virtual focal plane 45 indicated by the broken line is arranged so as to substantially coincide with the photothermal conversion layer (not shown) of the donor substrate 30, the near side becomes an on-focus condition that coincides with the focal length of the lens 42. Since the density is maximized and the back side is in an off-focus condition that deviates from the focal length, the irradiation density is reduced by blurring of light. When the irradiation light is scanned from the back to the front in such an arrangement, the time dependency of the irradiation intensity conceptually shown in FIG. 7B can be obtained.

  Note that the light irradiation method is not limited to scanning. For example, as shown in FIG. 9A, light covering the entire transfer region 38 of the donor substrate 30 can be irradiated. In this case, all the transfer materials can be transferred at once without scanning the irradiation light. Furthermore, as shown in FIG. 9B, step irradiation may be used in which light that partially covers the transfer region 38 of the donor substrate 30 is irradiated and then an unirradiated portion is irradiated. Also in this case, since the positions before and after the irradiation light may be overlapped, the alignment of the light irradiation can be greatly reduced.

(2) Donor substrate The donor substrate used in the present invention has a partition pattern on the photothermal conversion layer. Conventionally, forming a partition pattern which is a foreign substance other than the transfer material on the donor substrate is originally because the partition pattern itself may be peeled off and transferred, or impurities may be mixed into the transfer material from the partition pattern. It was considered undesirable. Furthermore, it is a foreign substance in a method in which a transfer material is heated to a relatively high temperature, such as a vapor deposition transfer method in which a photothermal conversion layer is installed on a donor substrate to absorb light and the transfer material is transferred by generated heat. Irradiating light so as to positively heat the partition pattern has been unprecedented as it is likely to deteriorate the performance of the device.

  However, the present invention enables high-definition patterning for the first time by irradiating light on the donor substrate provided with the photothermal conversion layer so as to heat the partition pattern simultaneously with the transfer material. The reason why this can be done is that, as described above, the intensity of light used can be reduced. For this reason, even when light is applied so that the transfer material and the partition pattern are heated at the same time, adverse effects on device performance due to separation of the partition pattern and degassing of the partition pattern can be minimized. .

  The support for the donor substrate is not particularly limited as long as it has a low light absorption rate and can stably form a photothermal conversion layer, a partition pattern, and a transfer material thereon. Depending on the conditions, a resin film can be used, and the resin materials include polyester, polyethylene, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, acrylic resin, polysulfone, polyethersulfone, polyphenylene sulfide, polyimide, polyamide, poly Examples include benzoxazole, epoxy resin, polypropylene, polyolefin, aramid resin, and silicone resin.

  In terms of chemical / thermal stability, dimensional stability, mechanical strength, and transparency, a preferred support is a glass plate. Soda lime glass, alkali-free glass, lead-containing glass, borosilicate glass, aluminosilicate glass, low expansion glass, quartz glass and the like can be selected according to the conditions. When the transfer process of the present invention is carried out in vacuum, a glass plate is a particularly preferred support because it is required that gas release from the support is small.

  Even if the photothermal conversion layer is heated to a high temperature, it is necessary to keep the temperature rise (thermal expansion) of the support itself within an allowable range. Therefore, the heat capacity of the support is preferably sufficiently larger than that of the photothermal conversion layer. Therefore, the thickness of the support is preferably 10 times or more the thickness of the photothermal conversion layer. The allowable range depends on the size of the transfer region, the required accuracy of patterning, and the like. However, for example, the photothermal conversion layer rises by 300 ° C. from room temperature, and the temperature rise of the support increases to 1/100 of 300 ° C. When it is desired to suppress the temperature to 3 ° C. or less, the thickness of the support is preferably 100 times or more the thickness of the photothermal conversion layer, and the temperature rise of the support is 1 ° C. which is 1/300 of 300 ° C. In the case where it is desired to suppress the following, the thickness of the support is more preferably 300 times or more the thickness of the photothermal conversion layer. Therefore, when 700 μm glass is used, the thickness of the photothermal conversion layer needs to be about 2 μm or less. In this way, even if the size is increased, the amount of dimensional displacement due to thermal expansion can be minimized, and high-accuracy patterning is possible.

  The photothermal conversion layer is not particularly limited as long as it is a material / configuration that efficiently absorbs light to generate heat and is stable against the generated heat. A thin film in which carbon black, graphite, titanium black, organic pigments, metal particles, or the like are dispersed in a resin can also be used. In the present invention, since the photothermal conversion layer may be heated to about 300 ° C., the photothermal conversion layer is preferably composed of an inorganic thin film having excellent heat resistance. It is particularly preferred that As metal materials, tungsten, tantalum, molybdenum, titanium, chromium, gold, silver, copper, platinum, iron, zinc, aluminum, cobalt, nickel, magnesium, vanadium, zirconium, silicon, carbon, etc. Those laminated thin films can be used.

  If necessary, an antireflection layer can be formed on the support side of the photothermal conversion layer. Further, an antireflection layer may be formed on the surface of the support on the light incident side. These anti-reflection layers are preferably optical interference thin films that use the difference in refractive index, and simple or mixed thin films such as silicon, silicon oxide, silicon nitride, zinc oxide, magnesium oxide, and titanium oxide, and laminated thin films thereof are used. it can.

  If necessary, a transfer auxiliary layer can be formed on the transfer material side of the photothermal conversion layer. An example of the function of the transfer auxiliary layer is a function of preventing the transfer material from being deteriorated by the catalytic effect of the heated photothermal conversion layer, and is an inert inorganic material such as tungsten, tantalum, molybdenum, silicon, oxide, or nitride. A thin film can be used. Another example of the function of the transfer auxiliary layer is a surface modification function when a transfer material is formed by a coating method, such as the rough surface thin film of the illustrated inert inorganic thin film or the porous film of the metal oxide. Can be used. Another example of the function of the transfer auxiliary layer is the uniform heating of the transfer material. For example, as shown in FIG. 10A, in order to uniformly heat the relatively thick transfer material 37, the heat transfer conductivity is increased. The transfer auxiliary layer 39 having a spike-like (or porous) structure can be formed from a material such as an excellent metal, and the transfer material 37 can be arranged to be carried in the gap. The transfer auxiliary layer having this function may be integrated with the photothermal conversion layer 37 as shown in FIG.

  Since the light-to-heat conversion layer needs to provide sufficient heat for evaporation of the transfer material, it is preferable that the heat capacity of the light-to-heat conversion layer is greater than that of the transfer material. Therefore, the thickness of the photothermal conversion layer is preferably thicker than the transfer material, and more preferably 5 times or more the thickness of the transfer material. The numerical value is preferably 0.02 to 2 μm, more preferably 0.1 to 1 μm. Since the photothermal conversion layer preferably absorbs 90% or more of light, and more preferably 95% or more, it is preferable to design the thickness of the photothermal conversion layer so as to satisfy these conditions. The transfer auxiliary layer is preferably designed to be thin within a range satisfying the required function so as not to prevent the heat generated in the light-to-heat conversion layer from being efficiently transferred to the transfer material.

  If the photothermal conversion layer is formed in the part where the transfer material exists, the planar shape is not particularly limited, but it is not preferable to irradiate the device substrate or partition material with light, so it is formed larger than the light irradiation range. There is a need to. Usually, it is formed on the entire surface of the donor substrate.

  As a method for forming the photothermal conversion layer and the transfer auxiliary layer, a known technique such as spin coating, slit coating, vacuum deposition, EB deposition, sputtering, ion plating, or the like can be used. When patterning, a known photolithography method, laser ablation, or the like can be used.

  The partition pattern is not particularly limited as long as it is a material / configuration that defines the boundary of the transfer material and is stable to the heat generated in the photothermal conversion layer. Examples of inorganic substances include oxides and nitrides such as silicon oxide and silicon nitride, glass and ceramics, and examples of organic substances include resins such as polyvinyl, polyimide, polybenzoxazole, polystyrene, acrylic, novolac, and silicone. . The well-known technique which manufactures the partition in a plasma television by the glass paste method can also be used. The thermal conductivity of the partition pattern is not particularly limited, but from the viewpoint of preventing heat from diffusing to the device substrate facing through the partition pattern, it is preferable that the thermal conductivity is small like an organic substance, and further, the patterning characteristics and As materials excellent in heat resistance, polyimide and polybenzoxazole can be exemplified as preferable materials.

  The method of forming the partition pattern is not particularly limited. When an inorganic material is used, known techniques such as vacuum deposition, EB deposition, sputtering, ion plating, CVD, and laser ablation are used. When an organic material is used, spin coating, Known techniques such as slit coating and dip coating can be used. The patterning method of the partition pattern is not particularly limited, and a known photolithography method can be used. The partition pattern may be patterned by an etching (or lift-off) method using a photoresist, or patterning is performed by directly exposing and developing the partition pattern using a material obtained by adding photosensitivity to the exemplified resin material. You can also Furthermore, a stamp method or an imprint method in which a mold is pressed against the partition pattern layer formed on the entire surface, an ink jet method or a nozzle jet method in which a resin material is directly formed by patterning, and various printing methods can be used.

  The shape of the partition pattern is not limited to the lattice (matrix) structure exemplified above, but, for example, as illustrated in FIG. 3, three types of transfer materials 37R, 37G, and 37B are formed on the donor substrate 30. When the pattern is formed, the planar shape of the partition pattern 34 may be a stripe extending in the y direction.

  The thickness of the partition pattern is not particularly limited. For example, as shown in FIG. 11, even if the partition pattern 34 is the same thickness as the transfer material 37 or thin, if the gap between the donor substrate 30 and the device substrate 20 is maintained, the transfer material evaporated at the time of transfer slightly spreads. Therefore, transfer can be performed without causing mixing between the transfer materials 37R, 37G, and 37B. The transfer material is preferably not in direct contact with the device substrate, and the gap between the donor substrate and the device substrate is preferably maintained in the range of 1 to 100 μm, and more preferably 2 to 20 μm. Therefore, the partition pattern is larger than the thickness of the transfer material. The thickness is preferably 1 to 100 μm, more preferably 2 to 20 μm. By making the partition pattern having such a thickness face the device substrate, the gap between the donor substrate and the device substrate can be easily maintained at a constant value, and the evaporated transfer material enters the other partition. The possibility can be reduced.

  The sectional shape of the partition pattern is preferably a forward tapered shape in order to facilitate the evaporation transfer material to be uniformly deposited on the device substrate. As illustrated in FIG. 2, when a pattern such as the insulating layer 14 is present on the device substrate 10, the width of the insulating layer 14 (especially the upper width) is larger than the width of the partition pattern 34 (especially the upper width). ) Is preferably wider. Further, at the time of alignment, it is preferable to arrange so that the width of the upper portion of the insulating layer 14 is within the width of the upper portion of the partition pattern 34. In this case, even if the partition pattern 34 is thin, the donor substrate 30 and the device substrate 10 can be held in a desired gap by increasing the thickness of the insulating layer 14. The typical width of the partition pattern is 5 to 50 μm and the pitch is 25 to 300 μm. However, the partition pattern may be designed to an optimum value depending on the application, and is not particularly limited.

  When using the coating method described later when placing the transfer material in the partition pattern, the upper surface of the partition pattern is used to prevent the solution from being mixed into other partitions or riding on the upper surface of the partition pattern. Liquid repellent treatment (surface energy control) can be applied. As the liquid repellent treatment, a liquid repellent material such as a fluorine-based material can be mixed with a resin material for forming a partition pattern, or a high concentration region of the liquid repellent material can be selectively formed on the surface or the upper surface. The partition pattern can be a multilayer structure of materials having different surface energies, and a known technique such as controlling the surface energy state by performing light irradiation or plasma treatment with a fluorine-containing material-containing gas after the partition pattern is formed. Can be used.

(3) Transfer material The transfer material is a material for forming a thin film constituting a device such as an organic EL element, an organic TFT, a photoelectric conversion element, and various sensors. When heated, both organic materials and inorganic materials including metals can be transferred from the donor substrate to the device substrate by evaporation, sublimation, or ablation sublimation, or by using adhesive changes or volume changes. That's fine. The transfer material may be a precursor for thin film formation, and the transfer film may be formed by being converted into a thin film formation material by heat or light before or during transfer.

  It is difficult to indicate the thickness of the transfer material in general according to the function and the number of transfers. For example, a typical transfer material for a single transfer of a donor material (electron injection material) such as lithium fluoride has a thickness of 1 nm or less. In addition, the film thickness of the transfer material of the electrode material may be 100 nm or more. In the case of the light emitting layer which is a suitable patterning thin film of the present invention, the thickness of the transfer material for one transfer is preferably 10 to 100 nm, and more preferably 20 to 50 nm.

  The method for forming the transfer material is not particularly limited, and a dry process such as vacuum evaporation or sputtering can be used. However, as a method that can easily cope with an increase in size, at least a solution composed of the transfer material and a solvent is placed in the partition pattern. It is preferable to transfer after applying and drying the solvent. Examples of the coating method include inkjet, nozzle coating, electropolymerization and electrodeposition, offset and flexographic printing, lithographic printing, relief printing, gravure, screen printing, and other various printing methods. In particular, in the present invention, it is important to accurately form a fixed amount of transfer material in each partition pattern. From this viewpoint, inkjet can be exemplified as a particularly preferable method.

  Without the partition pattern, the RGB organic EL material layers formed from the coating liquid are in contact with each other, and the boundary is not uniform, and a mixed layer is formed in no small amount. In order to prevent this, it is difficult to make the film thickness of the boundary region the same as the center when the gap is formed so as not to contact each other. In any case, since this boundary region cannot be transferred because it causes a reduction in device performance, it is necessary to selectively transfer a region narrower than the organic EL material pattern on the donor substrate. Accordingly, the width of the organic EL material that can actually be used is narrowed, and when an organic EL display is manufactured, the pixel has a small aperture ratio (the area of the non-light-emitting region is large). In addition, because transfer must be performed except for the boundary area, batch transfer cannot be performed. Therefore, it is necessary to irradiate light sequentially to R, G, and B, and to transfer them independently, and to conduct heat conduction in the lateral direction. Since it is necessary to suppress as much as possible, it is indispensable to irradiate high-intensity light for a short time, and the transfer material is likely to be thermally deteriorated. From the viewpoint of solving such a problem, the method of the present invention in which a donor substrate having a transfer material formed from a partition pattern and a coating liquid is used for batch transfer by irradiating with low energy light for a long time is used for the transfer material. This is an excellent transfer method from the viewpoint of suppressing thermal degradation to a minimum and not reducing productivity by batch transfer. As described with reference to FIG. 5B, the alignment accuracy at the time of irradiation does not require strict accuracy and is suitable as a transfer method for a large substrate.

  When applying a solution consisting of a transfer material and a solvent to the coating method, generally adding a surfactant, dispersant, etc., adjusts the viscosity, surface tension, dispersibility, etc. of the solution to make an ink. Often to do. However, in the present invention, if these additives exist as a residue in the transfer material, there is a concern that they will be taken into the transfer film even during transfer and adversely affect device performance. Accordingly, it is preferable to prepare the solution so that the purity of the transfer material after drying is 95% or more, and further 98% or more.

  As the solvent, known materials such as water, alcohol, hydrocarbon, aromatic compound, heterocyclic compound, ester, ether, ketone and the like can be used. In the ink jet method suitably used in the present invention, a solvent having a relatively high boiling point of 100 ° C. or higher, more preferably 150 ° C. or higher is used, and the solubility of the organic EL material is excellent. Methylpyrrolidone (NMP), dimethylimidazolidinone (DMI), γ-butyllactone (γBL), ethyl benzoate and the like can be exemplified as suitable solvents.

  When the transfer material satisfies all the solubility, transfer resistance, and device performance after transfer, it is preferable to dissolve the original transfer material in a solvent. When the transfer material is poor in solubility, the solubility can be improved by introducing a soluble group with respect to a solvent such as an alkyl group into the transfer material. When a soluble group is introduced into a prototype of a transfer material that excels in device performance, the performance may deteriorate. In that case, for example, the soluble material can be eliminated by heat at the time of transfer to deposit the original material on the device substrate.

  When transferring a transfer material into which a soluble group has been introduced, the transfer material has a soluble group in the solvent at the time of application to prevent the generation of gas and the incorporation of desorbed material into the transfer film. It is preferable to transfer the transfer material after converting or eliminating the soluble group by. For example, taking a material having a benzene ring as an example, as shown in Formula (1), a material having an acetyl group as a soluble group can be irradiated with light to be converted into a methyl group. In addition, as shown in Formula (2) and Formula (3), an intramolecular cross-linked structure such as an ethylene group or a diketo group is introduced as a soluble group, and then the original material is formed by a process of desorbing ethylene or carbon monoxide therefrom. It can also be restored. The conversion or elimination of the soluble group may be in a solution state before drying or in a solid state after drying. However, in consideration of process stability, it is preferably performed in a solid state after drying. Since the original molecule of the transfer material is often nonpolar, the molecular weight of the desorbed material is small so that the desorbed material does not remain in the transfer material when the soluble group is removed in the solid state. It is preferably polar (repulsive to the nonpolar prototype molecule). In order to remove oxygen and water adsorbed in the transfer material together with the desorbed material, it is preferable that the desorbed material easily reacts with these molecules. From these viewpoints, it is particularly preferable to convert or eliminate the solubilizing group in the process of eliminating carbon monoxide.

  Examples of the material having a benzene ring include condensed polycyclic compounds in addition to benzene itself. Examples of the condensed polycyclic compound include condensed polycyclic hydrocarbon compounds such as naphthalene, anthracene, naphthacene, pyrene, and perylene, as well as condensed polycyclic hetero compounds. Of course, these may be substituted or unsubstituted. The above conversion or elimination can be performed on one or more benzene rings of these compounds.

(4) Device substrate The support of the device substrate is not particularly limited, and the materials exemplified for the donor substrate can be used. In order to prevent the patterning accuracy from deteriorating due to the difference in thermal expansion due to temperature change when the transfer material is transferred with both facing each other, the difference in thermal expansion coefficient between the support of the device substrate and the donor substrate is 10 ppm / ° C. The following is preferable, and it is more preferable that these substrates are made of the same material. The glass plate exemplified as a particularly preferred support for the donor substrate can also be exemplified as a particularly preferred support for the device substrate. The difference in thickness between the two is not particularly limited.

  The device substrate may be composed of only a support during transfer, but it is general that a structure necessary for the device configuration is formed on the support in advance. For example, in the organic EL element shown in FIG. 1, the insulating layer 14 and the hole transport layer 16 can be formed by a conventional technique and used as a device substrate.

  A structure such as the insulating layer is not essential, but when the device substrate and the donor substrate are opposed to each other, the partition pattern of the donor substrate is prevented from coming into contact with the underlying layer formed on the device substrate and being damaged. Therefore, it is preferably formed in advance on the device substrate. For the formation of the insulating layer, the materials exemplified as the partition pattern of the donor substrate, the film formation method, and the patterning method can be used. With respect to the shape, thickness, width, and pitch of the insulating layer, the shape and numerical values exemplified in the partition pattern of the donor substrate can be exemplified.

(5) Transfer process The donor substrate and the device substrate are opposed to each other in a vacuum, and the transfer space can be taken out into the atmosphere while keeping the transfer space in a vacuum, and transfer can be performed. For example, the region surrounded by the partition pattern of the donor substrate and / or the insulating layer of the device substrate can be held in a vacuum. In this case, a vacuum sealing function may be provided at the periphery of the donor substrate and / or the device substrate. When a base layer of a device substrate, for example, a hole transport layer is formed by a vacuum process, a light emitting layer is patterned by the present invention, and an electron transport layer is also formed by a vacuum process, the donor substrate and the device substrate are opposed to each other in a vacuum. The transfer is preferably performed in a vacuum. In this case, for example, a method of aligning the donor substrate and the device substrate with high accuracy in a vacuum and maintaining the facing state is, for example, vacuum dropping / pasting of a liquid crystal material used in a liquid crystal display manufacturing process. A known technique such as a matching step can be used. Also, regardless of the transfer atmosphere, the donor substrate can be radiated or cooled during transfer, and when the donor substrate is reused, the donor substrate can be used as an endless belt. By using a photothermal conversion layer formed of a good conductor such as metal, the donor substrate can be easily held by an electrostatic method.

  In the present invention, since vapor deposition mode transfer is preferable, it is preferable to pattern a single transfer film in one transfer. However, by using the peeling mode and the ablation mode, for example, by forming a stacked structure of an electron transport layer / a light emitting layer on a donor substrate, and transferring it to the device substrate while maintaining the stacked state, The light-emitting layer / electron transport layer transfer film can be patterned once.

  The transfer atmosphere may be atmospheric pressure or reduced pressure. For example, in the case of reactive transfer, transfer can be performed in the presence of an active gas such as oxygen. In the present invention, since reduction of transfer damage of the transfer material is one of the problems, it is preferable to be in an inert gas such as nitrogen gas or under vacuum. By appropriately controlling the pressure, it is possible to promote uniformity of film thickness unevenness during transfer. From the viewpoint of reducing damage to the transfer material, reducing impurities mixed into the transfer film, and lowering the evaporation temperature, it is particularly preferable to be under vacuum.

  One of the problems of the conventional method in which the thin film formed by the coating method is directly used as the functional layer of the organic EL element is the film thickness unevenness. In the present invention, even when a transfer material is formed by a coating method, the same film thickness unevenness may occur. However, in the vapor deposition mode, which is the preferred transfer method in the present invention, the transfer material is loosened to the molecular (atomic) level during transfer. Therefore, the film thickness unevenness of the transfer film is reduced in order to deposit on the device substrate after being evaporated in the above state. Therefore, for example, at the time of application, the transfer material is particles made of molecular aggregates such as pigment, and even if the transfer material is not a continuous film on the donor substrate, it is evaporated and loosened to the molecular level during transfer. By doing so, a transfer film excellent in film thickness uniformity can be obtained on the device substrate.

  In particular, the low energy, long-time light irradiation employed in the present invention can reduce the deposited film thickness unevenness on the device substrate due to the difference in evaporation rate due to the film thickness unevenness of the transfer material.

  Next, a method for manufacturing a device using the patterning method of the present invention will be described. In the present invention, the device includes an organic EL element, an organic TFT, a photoelectric conversion element, various sensors, and the like. In the organic TFT, various electrodes such as an organic semiconductor layer, an insulating layer, a source, a drain, and a gate can be patterned, in an organic solar cell, an electrode and the like, and in a sensor, a sensing layer and an electrode can be patterned according to the present invention. Below, the organic EL element is mentioned as an example and the manufacturing method is demonstrated.

  FIG. 1 is a cross-sectional view showing an example of a typical structure of the organic EL element 10 (display). An active matrix circuit including the TFT 12 and the planarization layer 13 is formed on the support 11. The element portion is the first electrode 15 / hole transport layer 16 / light emitting layer 17 / electron transport layer 18 / second electrode 19 formed thereon. An insulating layer 14 that prevents a short circuit from occurring at the electrode end and defines a light emitting region is formed at the end of the first electrode. The device configuration is not limited to this example, for example, only one light emitting layer having a hole transport function and an electron transport function may be formed between the first electrode and the second electrode, The hole transport layer may be a hole injection layer and a hole transport layer, and the electron transport layer may be a multilayer structure of an electron transport layer and an electron injection layer, and the light emitting layer has an electron transport function. The electron transport layer may be omitted. Moreover, you may laminate | stack in order of 1st electrode / electron transport layer / light emitting layer / hole transport layer / second electrode. In addition, these layers may be a single layer or a plurality of layers. Although not shown, after the second electrode is formed, a protective layer, a color filter, sealing, or the like may be performed using a known technique or the patterning method of the present invention.

  In a color display, at least the light emitting layer needs to be patterned, and the light emitting layer is a thin film that is preferably patterned in the present invention. The insulating layer, the first electrode, the TFT and the like are often patterned by a known photolithography method, but may be patterned by the present invention. Moreover, when it is necessary to pattern at least one layer, such as a positive hole transport layer, an electron carrying layer, and a 2nd electrode, you may pattern by this invention. It is also possible to pattern only the R and G of the light emitting layer according to the present invention, and form the entire surface of the B light emitting layer and the R and G electron transporting layer thereon.

  As an example of manufacturing the organic EL element shown in FIG. 1, the photolithographic method is used up to the first electrode 15, the insulating layer 14 is patterned by a known technique using a photosensitive polyimide precursor material, and then the hole transport layer 16. Is formed on the entire surface by a known technique using a vacuum deposition method. Using this hole transport layer 16 as a base layer, the light emitting layers 17R, 17G, and 17B are patterned thereon according to the present invention shown in FIG. On top of this, if the electron transport layer 18 and the second electrode 19 are formed on the entire surface by a known technique using a vacuum deposition method or the like, the organic EL element can be completed.

  The light emitting layer may be a single layer or a plurality of layers, and the light emitting material of each layer may be a single material or a mixture of a plurality of materials. From the viewpoint of luminous efficiency, color purity, and durability, the light emitting layer preferably has a single layer structure of a mixture of a host material and a dopant material. Therefore, the transfer material for forming the light emitting layer is preferably a mixture of a host material and a dopant material.

  When the transfer material described below is used when the transfer material is arranged in the partition pattern, the transfer material can be formed by applying and drying a mixed solution of the host material and the dopant material. You may apply | coat the solution of host material and dopant material separately. Even if the host material and the dopant material are not uniformly mixed at the stage of forming the transfer material, they may be mixed uniformly at the time of transfer. Further, the concentration of the dopant material in the light emitting layer can be changed in the film thickness direction by utilizing the difference in evaporation temperature between the host material and the dopant material during transfer.

Examples of light-emitting materials include anthracene derivatives, naphthacene derivatives, pyrene derivatives, quinolinol complexes such as tris (8-quinolinolato) aluminum (Alq ₃ ), various metal complexes such as benzothiazolylphenol zinc complexes, bisstyrylanthracene derivatives, tetraphenyl Butadiene derivatives, coumarin derivatives, oxadiazole derivatives, benzoxazole derivatives, carbazole derivatives, distyrylbenzene derivatives, pyrrolopyridine derivatives, perinone derivatives, cyclopentadiene derivatives, oxadiazole derivatives, thiadiazolopyridine derivatives, rubrene, quinacridone derivatives, Phenoxazone derivatives, perinone derivatives, perylene derivatives, coumarin derivatives, chrysene derivatives, pyromethene derivatives, iridium complex materials called phosphorescent materials Low molecular weight material or the like, polyphenylene vinylene derivatives, polyparaphenylene derivatives, can be exemplified a polymer material such as a polythiophene derivative. In particular, examples of materials excellent in light emission performance and suitable for the patterning method of the present invention include anthracene derivatives, naphthacene derivatives, pyrene derivatives, chrysene derivatives, pyromethene derivatives, and various phosphorescent materials.

  The hole transport layer may be a single layer or a plurality of layers, and each layer may be a single material or a mixture of a plurality of materials. A layer called a hole injection layer is also included in the hole transport layer. From the viewpoint of hole transportability (low driving voltage) and durability, an acceptor material that promotes hole transportability may be mixed in the hole transport layer. Therefore, the transfer material for forming the hole transport layer may be made of a single material or a mixture of a plurality of materials. When the transfer material is arranged in the partition pattern, it can be formed by various methods as with the light emitting layer.

  The electron transport layer may be a single layer or a plurality of layers, and each layer may be a single material or a mixture of a plurality of materials. A layer called a hole blocking layer or an electron injection layer is also included in the electron transport layer. From the viewpoint of electron transport properties (low drive voltage) and durability, the electron transport layer may be mixed with a donor material that promotes electron transport properties. A layer called the electron injection layer is often discussed as this donor material. The transfer material for forming the electron transport layer may be made of a single material or a mixture of a plurality of materials. When the transfer material is arranged in the partition pattern, it can be formed by various methods as with the light emitting layer.

  Examples of the hole transport material and the electron transport material include various materials disclosed in Japanese Patent Application No. 2008-156282.

  Examples of the donor material include alkali metals and alkaline earth metals such as lithium, cesium, magnesium, and calcium, various metal complexes such as quinolinol complexes, and oxides and fluorides such as lithium fluoride and cesium oxide. be able to. An electron transport material or a donor material is one of materials that easily change in performance due to the combination with each of the RGB light emitting layers, and is exemplified as another preferable example that is patterned by the present invention.

  It is preferable that at least one of the first electrode and the second electrode is transparent in order to extract light emitted from the light emitting layer. In the case of bottom emission in which light is extracted from the first electrode, the first electrode is transparent, and in the case of top emission in which light is extracted from the second electrode, the second electrode is transparent. When the transfer material is arranged in the partition pattern, it can be formed by various methods as with the light emitting layer. Also, at the time of transfer, reactive transfer can be performed, for example, by reacting a transfer material with oxygen. As the transparent electrode material and the other electrode, conventionally known materials can be used as described in JP-A-11-214154, for example.

  The organic EL element in the present invention is not generally limited to the active matrix type in which the second electrode is formed as a common electrode. For example, the organic EL element is formed of a stripe electrode in which the first electrode and the second electrode intersect each other. It may be a simple matrix type or a segment type in which the display unit is patterned so as to display predetermined information. Examples of these applications include televisions, personal computers, monitors, watches, thermometers, audio equipment, automobile display panels, and the like.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated, this invention is not limited by these Examples.

Example 1
A donor substrate was prepared as follows. A non-alkali glass substrate of 38 × 46 mm and a thickness of 0.7 mm was used as a support, and after cleaning / UV ozone treatment, a 0.4 μm-thick tantalum film was formed on the entire surface by a sputtering method as a photothermal conversion layer. Next, the photothermal conversion layer was subjected to UV ozone treatment similar to the above, and then a positive polyimide photosensitive coating agent (DL-1000, manufactured by Toray Industries, Inc.) was spin-coated thereon, pre-baked and UV-exposed. Later, the exposed portion was dissolved and removed by a developer (NMD3, manufactured by Tokyo Ohka Co., Ltd.). The polyimide precursor film thus patterned was baked on a hot plate at 350 ° C. for 10 minutes to form a polyimide-based partition pattern. The partition pattern had a height of 2 μm and a cross section of a forward tapered shape. Openings exposing the photothermal conversion layer having a width of 80 μm and a length of 280 μm were arranged in the partition pattern at a pitch of 100 and 300 μm, respectively. On this substrate, a green solution (G) composed of a chloroform solution containing 1 wt% of a pyrene derivative is applied over the entire surface with a tetrahydronaphthalene solution containing 1 wt% of a naphthylanthracene derivative, and dried on a hot plate at 150 ° C. for 10 minutes. I let you. As a result, a transfer material composed of G having a thickness of 25 nm was formed in all sections.

The device substrate was produced as follows. A non-alkali glass substrate (manufactured by Geomatek Co., Ltd., sputtering film-formed product) having a thickness of 140 nm on which an ITO transparent conductive film was deposited was cut into 38 × 46 mm, and ITO was etched into a desired shape by a photolithography method. . Next, the polyimide precursor film patterned similarly to the donor substrate was baked at 300 ° C. for 10 minutes to form a polyimide-based insulating layer. The height of this insulating layer was 1.1 μm, and the cross section was a forward tapered shape. Openings exposing the ITO having a width of 70 μm and a length of 250 μm were arranged in the pattern of the insulating layer at a pitch of 100 and 300 μm, respectively. This substrate was subjected to UV ozone treatment, installed in a vacuum deposition apparatus, and evacuated until the degree of vacuum in the apparatus became 3 × 10 ⁻⁴ Pa or less. By a resistance heating method, 20 nm of copper phthalocyanine (CuPc) and 40 nm of NPD were stacked as a hole transport layer by vapor deposition over the entire light emitting region.

Next, the positions of the partition pattern of the donor substrate and the insulating layer of the device substrate were aligned and held in a vacuum of 3 × 10 ⁻⁴ Pa or less, and then taken out into the atmosphere. The transfer space partitioned by the insulating layer and the partition pattern was kept in a vacuum. In this state, a laser (light source: semiconductor laser diode) with a wavelength of about 800 nm is irradiated from the glass substrate side of the donor substrate so that about two sections of the transfer material and the section pattern existing between them are heated at the same time. The pyrene derivative of the material was transferred onto the hole transport layer which is the underlying layer of the device substrate. The laser intensity is 328 W / mm ² , the scan speed is 1.25 m / s, and a transfer material having a thickness of 25 nm is formed by repeated scanning irradiation 10 times while overlapping the lasers so as to be transferred to the entire light emitting region. Transfer was divided into 10 times.

The device substrate after the light emitting layer transfer was placed in the vacuum deposition apparatus again, and evacuated until the degree of vacuum in the apparatus became 3 × 10 ⁻⁴ Pa or less. E-1 shown below as an electron transport layer was deposited on the entire surface of the light emitting region by resistance heating. Next, 0.5 nm of lithium fluoride was deposited as a donor material (electron injection layer), and 100 nm of aluminum was deposited as a second electrode to produce an organic EL element having a 5 mm square light emitting region.

When voltage was applied to this element, light emission was observed instantaneously, and the initial luminous efficiency was 92 cd / A, 10 mA / cm ² , and the luminance retention rate after emitting light for 5 hours at a constant current density was 92. %Met.

Comparative Example 1
An organic EL device was produced in the same manner as in Example 1 except that a transfer material having a thickness of 25 nm was transferred by a single scan irradiation with a laser intensity of 585 W / mm ² . When voltage was applied to the device, weak light emission was observed instantaneously, but no light emission was observed within a few seconds. The initial luminous efficiency was estimated to be about 0.08 cd / A.

Sectional drawing which shows an example of the organic EL element by which the light emitting layer was patterned by this invention. Sectional drawing which shows an example of the light emitting layer patterning method of the organic EL element by this invention. The top view which shows an example of the light irradiation method in FIG. Sectional drawing explaining the problem in the conventional light irradiation arrangement | positioning. Sectional drawing which shows an example of the patterning method by this invention. The perspective view which shows another example of the light irradiation method in this invention. The conceptual diagram explaining the time change of the light intensity distribution and transfer material temperature in this invention. The perspective view which shows an example of the shaping | molding method of the irradiation light in this invention. The perspective view which shows another example of the light irradiation method in this invention. Sectional drawing explaining an example of the transfer auxiliary layer in this invention. Sectional drawing which shows another example of the patterning method by this invention.

Explanation of symbols

10 Organic EL elements (device substrates)
11 Support 12 TFT (including extraction electrode)
13 Flattening layer 14 Insulating layer 15 First electrode 16 Hole transport layer 17 Light emitting layer (17R, 17G, 17B)
18 Electron Transport Layer 19 Second Electrode 20 Device Substrate 21 Support 27 Transfer Film (27R, 27G, 27B)
30 Donor substrate 31 Support 33 Photothermal conversion layer 34 Partition pattern 37 Transfer material (37R, 37G, 37B)
38 Transfer area 39 Transfer auxiliary layer 41 Optical mask 42 Lens 43 Mirror 44 Light source 45 Virtual focal plane

Claims (7)

A light-to-heat conversion layer and a partition pattern are formed on the substrate, and a donor substrate in which the transfer material exists in the partition pattern is arranged opposite to the device substrate, and the width of each of m transfer materials (m is an integer of 2 or more). And the light-to-heat conversion layer is irradiated in multiple times to the light-to-heat conversion layer, and the m transfer materials are collectively applied to the device substrate. And transferring at least one transfer material out of the m transfer materials divided in n times (n is an integer of 2 or more) in the film thickness direction. The patterning method according to claim 1, wherein the light irradiation is scanning irradiation. 3. The patterning method according to claim 1, wherein m ≧ n. The patterning method according to claim 1, wherein a donor substrate having two or more different transfer materials is used. The patterning method according to claim 1, wherein at least a solution composed of a transfer material and a solvent is applied in a partition pattern, and the transfer material is transferred after the solvent is dried. 6. The patterning method according to claim 5, wherein at least one transfer material has a soluble group with respect to a solvent at the time of application, and the transfer material is transferred after conversion or elimination of the soluble group by heat or light after application. . A device manufacturing method, wherein at least one of the layers constituting the device is patterned by the method according to claim 1.

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