JP2008130703A - Method of manufacturing semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a semiconductor device which can have a semiconductor layer consisting of a good quality fine particle layer having no air gap and no projection by accurately controlling spacings between fine particles of bonded organic molecules. <P>SOLUTION: The method of manufacturing a semiconductor device having a fine particle layer 3 of fine particles s as bonded organic molecules arranged therein has first and second steps. In the first step, dendrimer molecules m as organic molecules are bonded to disperse the fine particles s covered with protective films of the dendrimer molecules m into a solvent to obtaine a dispersion solution, and the dispersion solution is coated on a substrate 1. In the second step, the solvent in the dispersion solution is removed to form a fine particle layer 3 of the fine particles s of bonded dendrimer molecules m arranged in the closest packed state. The fine particle layer 3 itself may be used as a semiconductor layer or may be used as a semiconductor layer with the dendrimer molecules m substituted with other organic molecules. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a semiconductor device including a semiconductor layer in which fine particles combined with organic molecules are arranged.

  A thin film transistor semiconductor device using an organic semiconductor can form a semiconductor thin film serving as a channel layer by coating at a low temperature. For this reason, the cost is lower than Si-based inorganic semiconductor transistors that use a silicon thin film formed as a semiconductor layer by a method that requires a vacuum processing chamber such as chemical vapor deposition (CVD). In addition, it can be formed on a flexible substrate without heat resistance such as plastic.

  Under such circumstances, as a semiconductor device that can be similarly manufactured using coating film formation, a network type conductive path is formed by fine particles made of a conductor or a semiconductor and organic semiconductor molecules bonded to the fine particles, and this conductive A semiconductor device using a path conductivity as a semiconductor layer controlled by an electric field and a manufacturing method thereof have been proposed. In such a semiconductor device, the functional groups at both ends of the organic semiconductor molecule are bonded to the fine particles, thereby forming a network-type conductive path in which the fine particles and the organic semiconductor molecules are connected to each other.

  In order to form such a conductive path (semiconductor layer), first, a dispersion in which fine particles are dispersed in a solvent is prepared. At this time, in order to prevent the fine particles from aggregating and precipitating, it is important to keep the fine particles covered with the protective film by binding the protective film molecules to the fine particles. As this protective film molecule, a chain-like insulating organic molecule is used. And after immersing a board | substrate in this dispersion liquid and taking out, a fine particle layer for one fine particle layer is formed on a board | substrate by evaporating a solvent.

  Subsequently, organic semiconductor molecules (linker molecules) having functional groups bonded to the fine particles at both ends are dissolved in a solvent, the substrate is immersed in this solution, and then the solvent is evaporated. As a result, the organic semiconductor molecules displace the protective film molecules and bind to the surface of the fine particles. At this time, the functional groups at both ends of the organic semiconductor molecule are bonded to different fine particles, and a first semiconductor layer in which the fine particles are connected in a network by the organic semiconductor molecules is formed.

  After the above, the formation of the fine particle layer and the replacement of the protective film molecules with organic semiconductor molecules are repeated to form the second and subsequent semiconductor layers (see Patent Document 1 below).

WO 2004/006337 (pages 23 to 24, page 25, lines 19 to 25) JP-A-2005-210207

  By the way, in the formation of the semiconductor layer having the above-described configuration, it is necessary to replace the protective film molecules of the fine particles with the organic semiconductor molecules (linker molecules). At this time, the distance between the particles and the length of the linker molecules are greatly different. And may adversely affect the shape of the semiconductor layer. For example, if the linker molecule is short relative to the interparticle distance, voids are generated in the formed semiconductor layer, and desired conductivity cannot be obtained. Conversely, when the linker molecule is long with respect to the interparticle distance, the fine particles are pushed out from the semiconductor layer, and it becomes difficult to connect the fine particles in a network form by the organic semiconductor molecules.

  For this reason, the interval between the fine particles before substitution with the semiconductor molecules is set to at least the maximum length of the organic semiconductor molecules, preferably a length that is easily linked by the organic semiconductor molecules, for example, a length that is about the natural length of the organic semiconductor molecules. It needs to be adjusted.

  However, when chain-like insulating organic molecules are used as the protective film molecules, as shown in FIG. 11 (1), the protective film molecules b bonded to the fine particles a enter and overlap each other, and FIG. As shown in 2), the protective film molecules b bonded to the fine particles a fall down in various directions. In particular, when the chain-like insulating molecules are 2 nm or more, it becomes very difficult to accurately control the distance L between the fine particles aa due to these phenomena.

  Accordingly, the present invention provides a method of manufacturing a semiconductor device that can control the interval between fine particles combined with organic molecules with high accuracy, and thereby obtain a semiconductor layer composed of fine particle layers having no voids and protrusions and having good film quality. The purpose is to provide.

  The present invention for achieving such an object is a method of manufacturing a semiconductor device having a fine particle layer in which fine particles to which organic molecules are bonded are arranged. In the first step, dendrimer molecules are bonded as organic molecules. Thus, the fine particles covered with the protective film made of the dendrimer molecules are dispersed in a solvent, and this dispersion solution is applied onto the substrate. In the next second step, the solvent in the dispersion solution is removed to form a fine particle layer in which fine particles combined with dendrimer molecules are arranged in a close-packed state. The fine particle layer itself may be used as a semiconductor layer, or may be used as a semiconductor layer by replacing dendrimer molecules with other organic molecules.

  In such a production method, a dendrimer molecule having a regular multi-branched structure is used as an organic molecule to be bonded to fine particles. For this reason, when the fine particles to which such dendrimer molecules are bonded are arranged in a close-packed state, dendrimer molecules bonded to adjacent fine particles do not enter each other and overlap each other. In addition, the dendrimer molecule having a multi-branched structure becomes bulky as the distance from the bonding portion to the fine particle increases. Therefore, in a state where a plurality of dendrimer molecules are bonded to the fine particles, these dendrimer molecules do not fall in one direction or many directions with respect to the fine particles. Dendrimer molecules have a single molecular weight with no molecular weight distribution and are precision polymers whose molecular weight is controlled with high accuracy. For this reason, the film thickness of the protective film formed by bonding the dendrimer molecules, that is, the interval between the fine particles is controlled with high accuracy and easily by the generation of the dendrimer molecules.

  As described above, according to the method for manufacturing a semiconductor device of the present invention, the interval between fine particles combined with organic molecules can be controlled with high accuracy, and thereby a fine particle layer having good film quality without voids and protrusions. It is possible to obtain a semiconductor layer made of

  Hereinafter, a method for manufacturing a semiconductor device of the present invention will be described in detail with reference to the drawings. The present invention is applied to the manufacture of a semiconductor device having a semiconductor layer using an organic material such as an organic thin film transistor. In each of the following embodiments, a manufacturing procedure of a semiconductor layer constituting a channel portion will be described in manufacturing such a semiconductor device.

<First Embodiment>
FIG. 1 is a diagram for explaining a first embodiment of the present invention.

  First, as shown in FIG. 1, first, a fine particle s whose outer periphery is covered with a protective film composed of a plurality of dendrimer molecules m is prepared by binding dendrimer molecules m as organic molecules to the fine particles s.

  If the fine particles s and the dendrimer molecules m are selected as a combination in which a fine particle film in which the fine particles s having the dendrimer molecules m bonded are closely packed has properties as a semiconductor layer, a conductive material and a semiconductor, respectively. Either a material or an insulating material may be used. The semiconductor layer referred to here is a layer whose conductivity is turned on / off by an electric field. In the semiconductor device manufactured here, the semiconductor layer has appropriate conductivity by the electric field applied to the semiconductor layer. It ’s fine.

  In particular, in the first embodiment, the dendrimer molecule m remains as a constituent element of the semiconductor layer. For this reason, it is preferable to select and use the dendrimer molecule m that has a certain degree of binding force with respect to the material constituting the fine particles s from the materials described above. Hereinafter, specific examples of the fine particles s and the dendrimer molecules m will be shown.

  As the conductive material constituting the fine particles s, gold (Au), silver (Ag), platinum (Pt), copper (Cu), aluminum (Al), palladium (Pd), titanium (Ti), chromium (Cr) , Manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), molybdenum (Mo), ruthenium (Ru), rhodium (Rh), tungsten (W), osmium (Os), iridium (Ir) Alternatively, alloys composed of these metals are used.

As the semiconductor material constituting the fine particles s, cadmium sulfide (CdS), cadmium selenide (CdSe), cadmium telluride (CdTe), gallium arsenide (GaAs), gallium phosphide (GaP), gallium nitride (GaN), Lead sulfide (PbS), lead selenide (PbSe), tin oxide (SnO ₂ ), indium oxide (In ₂ O ₃ ), indium phosphide (InP), titanium oxide (TiO ₂ ), zinc oxide (ZnO), zinc sulfide (ZnS), zinc selenide (ZnSe), zinc telluride (ZnTe), silicon carbide (SiC), germanium (Ge), or silicon (Si), ITO (tin doped indium oxide), FTO (fluorine doped) Tin oxide), ATO (antimony-doped tin oxide), AZO (aluminum-doped zinc oxide) Which doped material, or particles having a core-shell structure composed of these semiconductor used.

Further, as the insulating material constituting the fine particles s, silica (SiO ₂ ), iron oxide (Fe ₂ O ₃ , Fe ₃ O ₄ etc.), cobalt oxide (Co ₃ O ₄ ), nickel oxide (NiO), oxidation Aluminum (Al ₂ O ₃ ), barium titanate (BaTiO ₃ ) or the like is used.

  Various dendrimer molecules m can be used, but the dendrimer molecule m has one or more functional groups capable of binding to the fine particles s made of the material selected from the above. .

  The dendrimer molecule m may be a σ-based molecule shown in FIG. 2 (1), or may be a molecule containing a π-conjugated system as shown in FIG. 2 (2). Moreover, you may have hetero elements, such as Si, P, and GeBi, in the inside of a molecule | numerator.

  As shown in FIG. 1, the first method for producing the fine particles s having the dendrimer molecules m bonded thereto is as shown in FIG. 3 (1), in which the fine particles s are used as a core and dendron is bonded to the surface thereof. A method of growing dendrimer molecules m to a predetermined length by sequentially binding dendrons to the bound dendrons is exemplified. The method described in the following reference 1 is applied to such a method. In this case, it is preferable that the shape of each dendrimer molecule m grown around the fine particle s is a conical shape. However, it is assumed that only one fine particle s is included per one complex in which a plurality of dendrimer molecules m are bonded to the fine particle s.

Reference 1: R. Abu-Reziq et al., “J. Am. Chem. Soc.”, 2006, 128, p 5279. (Fe ₃ O ₄ / SiO ₂ )

  As a second method for producing the fine particles s to which the dendrimer m is bonded, as shown in FIG. 3 (2), a method in which the dendrimer molecules m are grown to a desired length and then bonded to the fine particles s is exemplified. The Even in this case, the shape of each dendrimer molecule m to be bonded to the fine particles s is preferably a conical shape. However, it is assumed that only one fine particle s is included per one complex in which a plurality of dendrimer molecules m are bonded to the fine particle s. The method described in the following references 2 to 5 is applied to such a method.

Reference 2: M. Daniel et al., “J. Am. Chem. Soc.” 2003, 125, p.2617. (Au),
Reference 3: KR Gopidas et al., “J. Am. Chem. Soc.”, 2003, 125, p.14180. (Au),
Reference 4: KR Gopidas et al., “Nano Lett.”, 2003, 3, p.1757. (Pd),
Reference 5: J. Locklin et al., “Chem. Mat.”, 2004, 16, p.5187. (CdSe)),

  Each of the references 1 to 5 shows a method in which the fine particles s are made of a material in parentheses at the end.

  In the first method and the second method as described above, the lengths of the plurality of dendrimer molecules m bound to the fine particles s are controlled with high precision by the number of dendron bonds (number of generations). For this reason, the fine particles s can be arranged at the center of the protective film composed of the dendrimer molecule m, which is a preferable production method for application to the present invention.

  Further, as a third method for producing the fine particles s to which the dendrimer m is bonded, as shown in FIG. 3 (3), a method in which the dendrimer molecules m are formed in advance and the fine particles s are taken into the interior is exemplified. The The method described in the following reference 6 is applied to such a method. In this case, the previously formed dendrimer molecule m is preferably spherical. However, it is assumed that only one fine particle s is included in each complex in which the fine particle s is incorporated into the dendrimer molecule m.

Reference 6: M. Zhao and R. M. Crooks, "Adv. Mat.", 1999, 11, p.217.

  In general, there are two methods for synthesizing a dendrimer molecule m: a branched approach shown in FIG. 4 (1) and a convergent approach shown in FIG. is there.

  Reference 7: S. M. Grayson and J. M. J. Frechet, “Chem. Rev.”, 2001, 101, p. 3819-3867

  The branched approach shown in FIG. 4 (1) is a technique in which dendrons are sequentially reacted to the dendrimer core or the dendron that is at the center, and spread outward. For this reason, in the branched approach, the number of reaction sites increases exponentially as the generation grows. Therefore, it is necessary to use dendron in a large excess, and the number of sites with incomplete reactions and the probability of side reactions increase. In addition, since the 1st method demonstrated in FIG. 3 (1) is a method which couple | bonds a dendron to the fine particle s sequentially, this branched type approach is used. This branching approach is also used for the second method described in FIG. 3 (2) or the third method described in FIG. 3 (3).

  On the other hand, the convergent approach shown in FIG. 4 (2) is a technique in which the outermost dendrons are connected and finally coupled to the core. For this reason, since there is always one reaction site, the yield is high, and in recent studies, a convergent approach is often used. Such a convergent approach is applied to the second method described in FIG. 3 (2) or the third method described in FIG. 3 (3).

  In particular, when the first method shown in FIG. 3 (1) is used, in order to advance the growth of the dendrimer with good controllability, as shown in FIG. 5 (1), the dendron m ′ bonded to the fine particles s is used. It is effective to carry out deprotection in which the end of is protected with a protecting group R and the protecting group R is eliminated when the next dendron is reacted. In addition, as shown in FIG. 5 (2), two types of dendrons ma and mb are used so that only dendron mb can be coupled to dendron ma and only dendron ma can be coupled to dendron mb. A method of alternately growing ma and mb is also effective.

As a specific example using the protecting group in FIG. 5 (1), a reaction as shown in FIG. 6 can be exemplified as described in Reference Document 8 below. Here, a case where 4: [G ₂ ]-(Ac) ₉ is synthesized as the dendrimer molecule m will be described.

  Reference 8: G. R. Newkome et al., “J. Org. Chem”, 1991, 56, p. 7167.

(A) 1: [G ₀ ] (1 g, 5 mmol) and 2: Dendron m ′ (1.98 g, 5 mmol) and triethylamine (Et ₃ N; 600 mg, 6 mmol) are dissolved in dehydrated benzene (25 mL) and stirred at 25 ° C. for 20 hours. To do. The reaction mixture is washed successively with aqueous sodium bicarbonate (NaHCO ₃ ) (10%), water, cold hydrochloric acid (10%), and brine. The organic layer is dried over sodium sulfate (Na ₂ SO ₄ ) and evaporated to give 3: [G ₁ ]-(Ac) ₃ .

(B) Dendrimer molecule 3: [G ₁ ]-(Ac) ₃ (1.5 g, 3 mmol) and anhydrous potassium carbonate (K ₂ CO ₃ ; 125 mg, 0.9 mmol) are dissolved in absolute ethanol (25 mL), Stir at 25 ° C for 15 hours. After the reaction, it is filtered and the solvent is distilled off. The filtered material was dissolved in a mixed solvent (40 mL) of acetone: water (1: 1), sodium periodate (NaIO ₄ ; 4.5 g, 21 mmol) and ruthenium (IV) oxide (RuO ₂ ; 65 mg, 486mmol) and stir vigorously at 25 ° C for 5 hours. After filtration, wash with acetone (50 mL) and evaporate. The solid is dissolved in aqueous sodium hydroxide (NaOH) (10%) and acidified with concentrated hydrochloric acid to give a white solid. Dehydrated white solid (400 mg, 1 mmol) and 2: Dendron m '(1.16 g, 3.5 mmol), dicyclohexylcarbodiimide (DCC; 620 mg, 3 mmol), 1-hydroxybenzotrizole (HOBt; 400 mg, 3 mmol) DMF And stir at 25 ° C for 24 hours. After the reaction, it is filtered and the solvent is distilled off. Dissolve in dichloromethane (50 mL), wash with hydrochloric acid (10%), water, aqueous sodium bicarbonate (NaHCO ₃ ) and brine in that order, and remove the solvent to obtain dendrimer molecule 4.

  Thereafter, the dendrimer molecule m is grown by repeating the operation (B). However, as the growth progresses, the binding portion of dendron increases, so the stirring time at room temperature is appropriately extended.

  Moreover, as a specific example using two types of dendrons of FIG. 5 (2), reaction as shown in FIG. 7 can be illustrated as described in the following reference 9.

Reference 9: R. Abu-Reziq et al., “J. Am. Chem. Soc.”, 2006, 128, p.5279.

First, 8 g of the silane-coupled particles [G ₀ ] are dispersed in 120 mL of dehydrated methanol and completely dispersed by applying ultrasonic waves for 35 minutes. To the solution is added 10 mL (111 mmol) of methyl acrylate and the mixture is heated at 50 ° C. for 5 days. After returning to room temperature, the particles are taken out, washed 3 times with dehydrated methanol, and dried under reduced pressure for 24 hours to obtain [G _0.5 ]. Disperse the dried [G _0.5 ] in 120 ml methanol again and sonicate for 35 minutes. Then 17.2 ml (257 mmol) of ethylenediamine is added dropwise at room temperature and the solution is heated at 50 ° C. for 5 days. The particles are taken out, washed with dehydrated methanol three times, and then dried under reduced pressure to obtain [G ₁ ] dendrimer molecules. Thereafter, the above reaction is repeated to grow the dendrimer molecule m. However, as the growth progresses, the bond portion of dendron increases, so the stirring time at room temperature is appropriately extended.

  Next, fine particles s covered with a protective film made of dendrimer molecules m as described above are dispersed in a solvent to prepare a dispersion solution. And this dispersion solution is apply | coated on a board | substrate. The dispersion solution is applied onto the substrate by, for example, a dipping method, a spin coating method, a casting method, an ink jet method, a screen printing method, a Langmuir-Blodget method, or a stamp method.

  After the above, the solvent in the dispersion solution applied on the substrate is removed. As a result, as shown in FIG. 8, a fine particle layer 3 in which fine particles s bonded with dendrimer molecules m are arranged in a close-packed state on the substrate 1 is formed. At this time, it is important to maintain the bonding state between the fine particles s and the dendrimer molecules m, and the solvent in the dispersion solution may be simply removed.

  At this time, if the evaporation rate of the solvent is too high, the evaporation rate of the solvent exceeds the self-organization rate of the fine particles s, so that the fine particles s are left on the spot, resulting in uneven distribution of the fine particles s. I can do it. Therefore, it is possible to control (slow down) the evaporation rate of the solvent by mixing the dispersion solution with an organic substance having a low vapor pressure, or by performing evaporation in a closed space filled with the solvent vapor. .

  In addition, when the dispersion solution is applied by a method similar to the so-called Langmuir-Blodgett method, fine particles having a hydrophobic surface are floated on a hydrophilic solvent (for example, water) so as to be densely arranged in a single layer, or On the contrary, fine particles having a hydrophilic surface are floated on a hydrophobic solvent so as to be closely arranged, and transferred onto a substrate.

  Further, in order to increase the film thickness of the fine particle layer 3 to a predetermined film thickness, the above-described dispersion solution coating step and the solvent removal step in the dispersion solution are repeated. Thereby, as shown in FIG. 9, the fine particle layer 3 is multilayered.

  As described above, the fine particle layer 3 in which the fine particles s bonded with the dendrimer molecules m are arranged in a close-packed state is formed as a semiconductor layer.

  If the substrate on which the semiconductor layer (fine particle layer 3) is formed has a structure in which a gate electrode, a gate insulating film, and source / drain electrodes are formed in advance, a bottom gate bottom contact type can be formed by forming the semiconductor layer. This completes the semiconductor device.

  In the manufacturing method according to the first embodiment described above, dendrimer molecules m having a regular multi-branched structure are used as organic molecules to be bonded to the fine particles s in the formation of the fine particle layer 3 serving as a semiconductor layer. For this reason, when the fine particles s covered with the protective film composed of such dendrimer molecules m are arranged in the close-packed state, the dendrimer molecules m bonded to the adjacent fine particles s do not enter each other and overlap each other. Further, the dendrimer molecule m having a multi-branched structure becomes bulky as the distance from the bonding portion to the fine particle s increases. For this reason, in a state where a plurality of dendrimer molecules m are bonded to the fine particles s, these dendrimer molecules m do not fall in one direction or many directions with respect to the fine particles s. The dendrimer molecule m is a single molecular weight precision polymer having no molecular weight or molecular weight distribution. For this reason, since the film thickness of the protective film formed by bonding dendrimer molecules, that is, the distance L between the fine particles s is almost twice the molecular length of the dendrimer molecules m, the generation of the dendrimer molecules m can be adjusted by adjusting the generation of the dendrimer molecules m. The distance L can be controlled with high accuracy.

  In particular, when the distance L between the fine particles s exceeds 2 nm, the control is difficult. However, even when L> 2 nm, it is possible to control this with good controllability.

  As described above, it is possible to obtain a semiconductor layer composed of the fine particle layer 3 having good film quality without voids and protrusions, and the carrier mobility of the semiconductor layer is ensured. As a result, it is possible to improve the characteristics of a semiconductor device using this semiconductor layer.

<Second Embodiment>
First, as in the first embodiment, as shown in FIG. 1, the fine particles s are covered with a protective film composed of a plurality of dendrimer molecules m by binding the fine particles s with dendrimer molecules m as organic molecules.

  However, in the second embodiment, the dendrimer molecule m is replaced with another organic molecule (linker molecule) in a later step. For this reason, the functional group possessed by the dendrimer molecule m has a weaker binding force to the fine particles s than the functional group possessed by the linker molecule. In addition to the fact that the dendrimer molecule m must be bonded to the fine particle s with a weak binding force, the bulk of the dendrimer molecule m must be fixed to the fine particle s. It is preferable to make it.

  The combination of the fine particles s and the dendrimer molecules m is selected from the viewpoint of the above-mentioned bonding force, because the fine particle film in which the fine particles s to which the dendrimer molecules m are bonded is most closely arranged does not need to exhibit properties as a semiconductor layer. Just do it.

  Thereafter, similarly to the first embodiment, after preparing a dispersion solution in which fine particles s covered with a protective film made of dendrimer molecules m are dispersed in a solvent, and then applying this dispersion solution on a substrate, Remove the solvent in the dispersion. As a result, as shown in FIG. 10A, the process is performed until the fine particle layer 3 formed by arranging the fine particles s having the dendrimer molecules m bonded on the substrate 1 in the close-packed state is formed.

  Next, the fine particle layer 3 is exposed to a solution in which an organic molecule (linker molecule) M having one or more functional groups having a strong binding force to the fine particles s is dissolved. As a result, as shown in FIG. 10 (2), the dendrimer molecule (m) is replaced with an organic molecule (linker molecule) M, and the organic molecules (linker) are arranged on the fine particles s arranged in a state where the interval is controlled with high accuracy. The fine particle layer 5 to which (molecule) M is bonded is formed.

  The organic molecule (linker molecule) M used here is a functional group possessed by the organic molecule (linker molecule) M among the organic molecules (linker molecule) M having one or more functional groups having a strong binding force to the fine particles s. An appropriate combination is selected depending on the ease of bonding with the fine particles s and the conductivity required for the fine particle layer 5 composed of the fine particles a and the organic molecules (linker molecules) M.

  In particular, the organic molecule (linker molecule) M has two or more functional groups, and these organic functional groups (linker molecules) M and the fine particles s are alternately connected to the adjacent fine particles s. In the case of forming a bonded network, a dendrimer having a length between functional groups equal to the interval L between the fine particles s, that is, a molecular length half of the length between the functional groups is provided. It is preferable to use the fine particles. In addition, when it is not necessary to form a network, an organic molecule (linker molecule) M having only one functional group having a strong binding force to the fine particles s is used. It is preferable to select the dendrimer so that it is ½ of the interval L between s, that is, approximately the same as the molecular length of the dendrimer.

  For this substitution, an immersion method, a casting method, or the like can be used. At this time, in order to remove the dendrimer molecule m released from the fine particles s, it is preferable in terms of the process to select a solvent that can also dissolve the dendrimer molecule m as the solution in which the organic molecule (linker molecule) M is dissolved. The free dendrimer molecule m may be removed later by performing a rinsing step.

  Specifically, a fine particle film 3 formed of fine particles s (for example, gold nanoparticles) to which dendrimer molecules m are bonded is immersed in a 1 mM ethanol solution of biphenyldithiol that is an organic molecule (linker molecule) M for 24 hours. Rinse with ethanol several times and then dry.

  Further, in order to increase the thickness of the fine particle layer 5 in which the organic molecules (linker molecules) M are bonded to the fine particles s to a predetermined thickness, the above-described dispersion solution coating step and the solvent removal step in the dispersion solution are performed. And the replacement step of the dendrimer molecule m and the organic molecule (linker molecule) M is repeated. Thereby, the fine particle layer 5 is multilayered.

  As described above, the fine particle layer 5 formed by arranging the fine particles s combined with the organic molecules (linker molecules) M is formed as a semiconductor layer.

  If the substrate on which the semiconductor layer (fine particle layer 5) is formed has a structure in which a gate electrode, a gate insulating film, and source / drain electrodes are formed in advance, a bottom gate bottom contact type can be formed by forming the semiconductor layer. This completes the semiconductor device.

  In the manufacturing method of the second embodiment described above, in the formation of the fine particle layer 5 serving as the semiconductor layer, first, as in the first embodiment, the step of arranging the fine particles s to which the dendrimer molecules m are bonded in a close-packed state. Therefore, the interval between the fine particles s is controlled with high accuracy by adjusting the generation of the dendrimer molecule m. In this state, in order to replace the dendrimer molecule m with another organic molecule (linker molecule) M, the fine particle layer 5 in which the organic molecule (linker molecule) M is bonded to the fine particles arranged at a precisely controlled interval L is formed. It becomes possible to obtain.

  As described above, a semiconductor layer composed of the fine particle layer 5 with good film quality can be obtained, and carrier mobility of the semiconductor layer is ensured. As a result, it is possible to improve the characteristics of a semiconductor device using this semiconductor layer.

  In each of the above-described embodiments, the configuration in which the present invention is applied to the formation of the semiconductor layer of the channel portion in the bottom gate bottom contact type semiconductor device has been described. However, the present invention can be similarly applied to any semiconductor device provided with a thin semiconductor layer, and the same effect can be obtained.

It is a figure of the fine particle which combined the dendrimer molecule produced in 1st Embodiment. It is a structural diagram showing an example of a dendrimer molecule used in the first embodiment. It is a figure which shows three examples of the method of producing the microparticles | fine-particles conjugated with the dendrimer molecule m. It is a figure which shows the synthetic | combination method of the dendrimer molecule m. It is a figure which shows the synthetic | combination method for controlling the shape of the dendrimer molecule m precisely. It is a figure which shows the 1st specific example of a dendrimer molecule synthesis. It is a figure which shows the 2nd specific example of a dendrimer molecule synthesis. It is process drawing (the 1) for demonstrating 1st Embodiment. It is process drawing (the 2) for demonstrating 1st Embodiment. It is process drawing for demonstrating 2nd Embodiment. It is a figure explaining the subject of the conventional manufacturing method.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Substrate, 3, 5 ... Fine particle layer, m ... Dendrimer molecule, M ... Organic molecule (linker molecule), s ... Fine particle

Claims (8)

A method of manufacturing a semiconductor device having a fine particle layer in which fine particles combined with organic molecules are arranged,
A first step of dispersing fine particles covered with a protective film composed of the dendrimer molecules in a solvent by binding the dendrimer molecules as organic molecules, and applying the dispersion solution on the substrate;
Performing a second step of forming a fine particle layer in which fine particles covered with the protective film are arranged in a close-packed state by removing a solvent in the dispersion solution applied on the substrate. A method for manufacturing a semiconductor device. In the manufacturing method of the semiconductor device according to claim 1,
The fine particle layer is used as a semiconductor layer. A method of manufacturing a semiconductor device, wherein: In the manufacturing method of the semiconductor device according to claim 1,
The method for manufacturing a semiconductor device, wherein the fine particle layer is multilayered by repeatedly performing the first step and the second step. In the manufacturing method of the semiconductor device according to claim 1,
After the second step,
A third step of replacing the dendrimer molecule with the organic molecule by exposing the fine particle layer to a solution in which an organic molecule having a functional group capable of binding to the fine particle is dissolved is performed. . In the manufacturing method of the semiconductor device according to claim 4,
The fine particle layer is used as a semiconductor layer. A method of manufacturing a semiconductor device, wherein: In the manufacturing method of the semiconductor device according to claim 4,
The method of manufacturing a semiconductor device, wherein the fine particle layer is multilayered by repeatedly performing the first to third steps. In the manufacturing method of the semiconductor device according to claim 3,
In the third step, the organic molecule is bonded to two fine particles, thereby forming a network in which the organic molecules and the fine particles are alternately bonded. In the manufacturing method of the semiconductor device according to claim 1,
Before the first step,
A step of synthesizing the fine particles to which the dendrimer molecules are bonded is performed by bonding a dendrimer core to the fine particles, and sequentially growing the number of generation dendrons required for the dendrimer core to grow dendrimer molecules. A method for manufacturing a semiconductor device.

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