JP2007318112A - Semiconductor device, and method of fabricating semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce an influence that the characteristic of an end portion of a channel forming region of a semiconductor film affects on the characteristic of a transistor. <P>SOLUTION: A semiconductor film, a gate insulating film, and a first conductive film are sequentially laminated on a substrate to form a laminate, and by removing the laminate, a plurality of laminates are provided in an island shape, then an insulating film is formed so as to cover the laminate provided in an island shape. Then, a part of the insulating film is removed so that its height is approximately equal to the height of the surface of the first conductive film to expose the surface of the first conductive film, and a second conductive film is formed on the first insulating film and on a remaining first insulating film. Then a resist is formed on the second conductive film, and the first conductive film and the second conductive film are selectively removed, with the resist as a mask. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a semiconductor device and a method for manufacturing the semiconductor device.

  In recent years, a semiconductor device in which a thin film transistor (TFT) is formed over a substrate having an insulating surface such as glass and the thin film transistor is used as a switching element or the like has been actively produced. The thin film transistor is provided so that an island-shaped semiconductor film is formed on a substrate having an insulating surface by a CVD method, a photolithography process, or the like, and a part of the island-shaped semiconductor film is used as a channel formation region. Yes. (For example, Patent Document 1)

FIG. 19 shows a schematic diagram of a general thin film transistor. The thin film transistor includes an island-shaped semiconductor film 903 over an insulating film 902 that functions as a base film over a substrate 901, and serves as a gate electrode through the gate insulating film 904 so as to cross the island-shaped semiconductor film 903. A functional conductive film 905 is provided. The semiconductor film 903 includes a channel formation region 903a formed in a region overlapping with the conductive film 905 and an impurity region 903b which forms a source region or a drain region. In addition, a conductive film 907 for forming a source electrode or a drain electrode is provided so as to be electrically connected to the impurity region 903b. 19B and 19C show cross-sectional structures between C _{1 and} D _{1 and} between C _{2 and} D ₂ in FIG. 19A, respectively.
JP 08-018055

  However, when the semiconductor film is provided in an island shape, a plurality of elements can be separated from each other, but a step is generated at the end of the semiconductor film, so that the end of the semiconductor film is sufficiently covered with the gate insulating film. There is a problem that cannot be done. Further, in recent years, in order to reduce the power consumption and the operation speed of the thin film transistor, it is desired to reduce the thickness of the gate insulating film. When the gate insulating film is thinly formed, the gate insulation at the end of the semiconductor film is desired. The problem of poor film coating becomes significant. When the end portion of the semiconductor film cannot be sufficiently covered with the gate insulating film, a short circuit or the like may occur between the conductive film forming the gate electrode and the semiconductor film at the end portion of the semiconductor film. In particular, thinning of the gate insulating film at the edge of the channel formation region of the semiconductor film causes problems such as deterioration of the electrical characteristics of the thin film transistor due to leakage current at the edge of the gate electrode and the channel region of the semiconductor film. To do.

  In addition, when fixed charges are trapped at the edge of the semiconductor film due to the breakdown of the gate insulating film or the manufacturing process, the characteristics of the channel formation region at the edge change compared to the center of the semiconductor film. Problems such as an influence on the electrical characteristics of the thin film transistor occur.

  In view of the above problems, an object of the present invention is to provide a semiconductor device and a method for manufacturing the semiconductor device in which the influence of the characteristics of the end portion of the channel formation region of the semiconductor film on the electrical characteristics of the transistor is reduced.

  The semiconductor device of the present invention includes a semiconductor film provided in an island shape on a substrate, an insulating film provided in contact with a side surface of the semiconductor film, a gate insulating film provided in contact with the surface of the semiconductor film, a gate A first conductive film provided over the insulating film; and a second conductive film provided in contact with the surface of the first conductive film and the surface of the insulating film; It is provided so that a part of the first conductive film and a part of the end of the first conductive film coincide with each other. The position of a part of the end portion of the semiconductor film and the position of a part of the end portion of the first conductive film coincide with each other in a state where the side surface of the semiconductor film and the side surface of the first conductive film are approximately aligned at least in a part. Say. Moreover, the surface here refers to the upper surface.

  In addition, a semiconductor device of the present invention includes a semiconductor film provided in an island shape over a substrate, an insulating film provided in contact with part of a side surface of the semiconductor film, and a gate provided in contact with the surface of the semiconductor film. An insulating film; a first conductive film provided over the gate insulating film; a second conductive film provided in contact with the surface of the first conductive film and the surface of the insulating film; and A side wall and a side wall provided in contact with the side surface of the second conductive film so that a part of the end portion of the semiconductor film and a part of the end portion of the first conductive film are aligned with each other. Is provided. In the above structure, the end portion of the insulating film and the end portion of the second conductive film may be provided so as to coincide with each other.

  In addition, a semiconductor device of the present invention is provided with a semiconductor film having a channel formation region, a source region, a drain region, and an impurity region having a conductivity type different from that of the source region and the drain region, in contact with a side surface of the semiconductor film. The insulating film formed, the gate insulating film provided in contact with the surface of the semiconductor film, the first conductive film provided on the gate insulating film, the surface of the first conductive film, and the surface of the insulating film The channel formation region is provided between the source region and the drain region, and the impurity region is an end portion of the semiconductor film, and the channel formation region and the source region are provided. It is provided adjacent to the region and the drain region, and is provided so that the position of a part of the end portion of the semiconductor film coincides with the position of a part of the end portion of the first conductive film.

  In addition, a semiconductor device of the present invention includes a semiconductor film provided in an island shape over a substrate, a first insulating film provided in contact with a side surface of the semiconductor film, and a tunnel provided in contact with the surface of the semiconductor film. An insulating film, a charge storage layer provided on the tunnel insulating film, a second insulating film provided in contact with the surface of the charge storage layer and the surface of the first insulating film, and the second insulating film The conductive film is formed, and is provided so that the position of a part of the end portion of the semiconductor film is coincident with the position of a part of the end portion of the charge storage layer.

  In addition, a semiconductor device of the present invention includes a semiconductor film provided in an island shape over a substrate, a first insulating film provided in contact with part of a side surface of the semiconductor film, and a surface of the semiconductor film. A tunnel insulating film, a charge storage layer provided on the tunnel insulating film, a second insulating film provided in contact with the surface of the charge storage layer and the surface of the first insulating film, and a second insulation A conductive film formed on the film; a charge storage layer; a second insulating film; and a sidewall provided in contact with a side surface of the conductive film; It is provided so that the positions of a part of the end portions of the layers coincide. In the above structure, the end portion of the first insulating film, the end portion of the second insulating film, and the end portion of the conductive film may be aligned with each other.

  According to a method for manufacturing a semiconductor device of the present invention, a stacked body in which a semiconductor film, a gate insulating film, and a first conductive film are sequentially stacked is formed over a substrate, and the stacked body is selectively removed to provide an island shape. Forming an insulating film so as to cover the laminated body provided in an island shape, and removing a part of the insulating film so that the height of the surface of the first conductive film is approximately the same Then, the surface of the first conductive film is exposed, a second conductive film is formed on the first conductive film and the remaining insulating film, a resist is formed on the second conductive film, and the resist is used as a mask. The first conductive film and the second conductive film are selectively removed.

  In addition, in the method for manufacturing a semiconductor device of the present invention, an island shape is formed by forming a stacked body in which a semiconductor film, a gate insulating film, and a first conductive film are stacked in order on a substrate, and selectively removing the stacked body. The insulating film is formed so as to cover the stacked body provided in an island shape, and a part of the insulating film is formed so that the height of the surface of the first conductive film is approximately the same. The surface of the first conductive film is removed to be removed, a second conductive film is formed over the first conductive film and the remaining insulating film, a resist is formed over the second conductive film, and the resist is formed. As a mask, the first conductive film and the second conductive film are selectively removed, and the first impurity element is selectively introduced into the semiconductor film using the first conductive film and the second conductive film as a mask. Thus, a first impurity region is formed in the semiconductor film and is in contact with the side surfaces of the first conductive film and the second conductive film. Side walls are formed so that the second impurity element is selectively introduced into the semiconductor film by using the first conductive film, the second conductive film, and the sidewalls as a mask, whereby the second impurity is added to the semiconductor film. Form a region.

  In addition, in the method for manufacturing a semiconductor device of the present invention, an island shape is formed by forming a stacked body in which a semiconductor film, a first insulating film, and a charge storage layer are stacked in order on a substrate, and selectively removing the stacked body. The second insulating film is formed so as to cover the stacked body provided in an island shape, and a part of the second insulating film is formed so that the height substantially coincides with the surface of the semiconductor film. Is removed to expose the surface of the charge storage layer, a third insulating film is formed on the charge storage layer and the remaining second insulating film, and a conductive film is formed on the third insulating film. A resist is formed thereon, and the first insulating film, the charge storage layer, the third insulating film, and the conductive film are selectively removed using the resist as a mask.

  An insulating film is formed so as to be in contact with a side surface of the semiconductor film at an end portion of the island-shaped semiconductor film which overlaps with the conductive film functioning as a gate electrode and a gate wiring, and the conductive film is provided over the insulating film. It is possible to prevent disconnection of the conductive film at the end, and to reduce the influence on the transistor due to the characteristics of the end of the channel region of the semiconductor film.

  Embodiments of the present invention will be described below with reference to the drawings. However, the present invention is not limited to the following description, and it is easily understood by those skilled in the art that modes and details can be variously changed without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the description of the embodiments below. Note that in the structures of the present invention described below, the same reference numerals may be used in common in different drawings.

(Embodiment 1)
In this embodiment mode, an example of a semiconductor device of the present invention and a manufacturing method thereof will be described with reference to drawings.

First, a semiconductor device described in this embodiment is illustrated in FIG. 1 (A) is a top view of the semiconductor device shown in this embodiment, in FIG. 1 (B) is a cross-sectional view taken along _a 1 -b ₁ in FIG. 1 _(A), the cross-sectional view of a 2 -b ₂ Is shown in FIG.

  The semiconductor device described in this embodiment includes a thin film transistor 200a including a semiconductor film 203 provided in an island shape over an insulating film 202 over a substrate 201, and a thin film transistor 200b including a semiconductor film 213. The thin film transistor 200 a includes a first conductive film 205 and a second conductive film 206 which are formed over the semiconductor film 203 with a gate insulating film 204 interposed therebetween. The thin film transistor 200b includes a first conductive film 215 and a second conductive film 206 which are formed over the semiconductor film 213 with a gate insulating film 214 interposed therebetween.

  In FIG. 1, the semiconductor film 203 in the thin film transistor 200a includes a channel formation region 203a in a region overlapping with the first conductive film 205, and functions as a source region or a drain region adjacent to the channel formation region 203a. 1 impurity region 203b. The semiconductor film 213 in the thin film transistor 200b includes a channel formation region 213a in a region overlapping with the first conductive film 215, and a first impurity region 213b that functions as a source region or a drain region adjacent to the channel formation region 213a. have. Note that the first impurity region 213b functioning as a source region or a drain region is provided to be separated with a channel formation region 213a interposed therebetween.

  In the semiconductor device described in this embodiment, the insulating film 207 is provided between the thin film transistors 200a and 200b. The insulating film 207 is provided in contact with at least the side surfaces of the semiconductor film 203 and the semiconductor film 213. That is, the semiconductor film 203 and the semiconductor film 213 are provided surrounded by the insulating film 207. The insulating film 207 may be provided in contact with part of the side surfaces of the gate insulating films 204 and 214 and part of the side surfaces of the first conductive films 205 and 215.

  The second conductive film 206 is provided over the first conductive films 205 and 215 and the insulating film 207 so as to be in contact with the surfaces (upper surfaces) of the first conductive films 205 and 215 and the insulating film 207. That is, in the semiconductor device described in this embodiment, the gate insulating films 204 and 214 and the conductive films 205 and 215 are not formed over the insulating film 207 even when part of the side surfaces is in contact with the insulating film 207. .

  The insulating film 207 is provided so that the surface height of the insulating film 207 and the first conductive films 205 and 215 are approximately the same. Note that the surface height approximately matches that of the surface of the insulating film 207 and the surface of the first conductive film 205 and 215, as well as the case where they do not completely match. Shall be. The difference in height between the surface of the first conductive films 205 and 215 and the surface of the insulating film 207 is the stacked structure of the semiconductor film 203, the gate insulating film 204, and the first conductive film 205, or the semiconductor film 213 and the gate insulating film. By providing the layer 214 so as to be smaller than the height value of the stacked structure of the first conductive film 215 and the first conductive film 215, a step at the end portions of the semiconductor films 203 and 213 can be reduced.

  As a result, even when the gate insulating film is thinned, deterioration of the electrical characteristics of the thin film transistor due to leakage current with the gate electrode at the end of the channel formation region of the semiconductor film can be suppressed.

  In the thin film transistors 200a and 200b, the first conductive films 205 and 215 function as gate electrodes, and the second conductive film 206 functions as a gate electrode and a gate wiring.

  Note that a gate electrode refers to a portion of a conductive film that overlaps with a semiconductor that forms a channel region, an LDD (Lightly Doped Drain) region, or the like with a gate insulating film interposed therebetween. A gate wiring refers to a wiring for connecting a gate electrode to another thin film transistor or for connecting a gate electrode to another wiring. However, there is a portion which functions as a gate electrode and also functions as a gate wiring (for example, the conductive film 206 in this embodiment). Such a region may be called a gate electrode or a gate wiring. That is, there is a region where the gate electrode and the gate wiring cannot be clearly distinguished. For example, when there is a channel region that overlaps with an extended gate wiring, the region functions as a gate wiring, but also functions as a gate electrode. Therefore, such a region may be called a gate electrode or a gate wiring.

Next, an example of a method for manufacturing the semiconductor device illustrated in FIG. 1 will be described with reference to FIGS. 2 and 3 are cross-sectional views taken along line a ₁ -b ₁ in FIG. 1A, and FIGS. 4 and 5 are cross-sectional views taken along line a ₂ -b ₂ in FIG. Yes.

  First, the semiconductor film 223, the gate insulating film 224, and the first conductive film 225 are stacked over the substrate 201 with the insulating film 202 interposed therebetween (FIGS. 2A and 4A).

  The substrate 201 is selected from a glass substrate, a quartz substrate, a ceramic substrate, a metal substrate (for example, a stainless steel substrate), and a semiconductor substrate such as a Si substrate. In addition, a substrate such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), or acrylic can be selected as the plastic substrate.

  The insulating film 202 is formed using silicon oxide, silicon nitride, silicon oxynitride (SiOxNy) (x> y> 0), silicon nitride oxide (SiNxOy) (x> y> 0), or the like using a CVD method, a sputtering method, or the like. It is formed using an insulating material. For example, in the case where the insulating film 202 has a two-layer structure, a silicon nitride oxide film may be formed as the first insulating film and a silicon oxynitride film may be formed as the second insulating film. Alternatively, a silicon nitride film may be formed as the first insulating film, and a silicon oxide film may be formed as the second insulating film. In this manner, by forming the insulating film 202 functioning as a blocking layer, alkali metal such as Na or alkaline earth metal from the substrate 201 can be prevented from adversely affecting the element formed thereon. Note that the insulating film 202 may be omitted when quartz is used for the substrate 201.

  The semiconductor film 223 is formed using an amorphous semiconductor film or a crystalline semiconductor film. As for the crystalline semiconductor film, an amorphous semiconductor film formed over the insulating film 202 is crystallized by heat treatment or laser light irradiation, and after the crystalline semiconductor film formed over the insulating film 202 is made amorphous. , Recrystallized materials, and the like.

When crystallization or recrystallization is performed by laser light irradiation, an LD-excited continuous wave (CW) laser (YVO ₄ , second harmonic (wavelength 532 nm)) can be used as a laser light source. The second harmonic is not particularly limited to the second harmonic, but the second harmonic is superior to higher harmonics in terms of energy efficiency. When the semiconductor film is irradiated with the CW laser, energy is continuously given to the semiconductor film. Therefore, once the semiconductor film is in a molten state, the molten state can be continued. Furthermore, the solid-liquid interface of the semiconductor film can be moved by scanning with a CW laser, and crystal grains that are long in one direction can be formed along the direction of this movement. The solid laser is used because the output stability is higher than that of a gas laser or the like, and stable processing is expected. Note that not only the CW laser but also a pulse laser having a repetition frequency of 10 MHz or more can be used. If a pulse laser with a high repetition frequency is used, the semiconductor film can always remain in a molten state if the laser pulse interval is shorter than the time from when the semiconductor film melts until it solidifies. A semiconductor film including crystal grains that are long in one direction can be formed. Other CW lasers and pulse lasers with a repetition frequency of 10 MHz or more can also be used. For example, examples of the gas laser include an Ar laser, a Kr laser, and a CO ₂ laser. Examples of the solid-state laser include a YAG laser, a YLF laser, a YAlO ₃ laser, a GdVO ₄ laser, a KGW laser, a KYW laser, an alexandrite laser, a Ti: sapphire laser, a Y ₂ O ₃ laser, and a YVO ₄ laser. A YAG laser, a Y ₂ O ₃ laser, a GdVO ₄ laser, a YVO ₄ laser, or the like is also referred to as a ceramic laser. Examples of the metal vapor laser include a helium cadmium laser. In addition, it is preferable to emit laser light in TEM ₀₀ (single transverse mode) in a laser oscillator because energy uniformity of a linear beam spot obtained on the irradiated surface can be improved. In addition, a pulsed excimer laser may be used.

For the gate insulating film 224, silicon oxide, silicon nitride, silicon oxynitride (SiOxNy) (x>y> 0), silicon nitride oxide (SiNxOy) (x>y> 0), or the like is used. Such an insulating film is formed by a vapor deposition method or a sputtering method. In addition, the semiconductor film 223 includes an atmosphere containing oxygen (for example, an atmosphere of oxygen (O ₂ ) and a rare gas (including at least one of He, Ne, Ar, Kr, and Xe), or oxygen and hydrogen (H ₂ ). And a rare gas atmosphere) or an atmosphere containing nitrogen (for example, an atmosphere containing nitrogen (N ₂ ) and a rare gas (including at least one of He, Ne, Ar, Kr, and Xe), or nitrogen, hydrogen, and a rare gas. The gate insulating film 224 can also be formed by performing high-density plasma treatment under an atmosphere or an atmosphere containing NH ₃ and a rare gas and oxidizing or nitriding the surface of the semiconductor film 223.

The high density plasma treatment is performed in an atmosphere of the gas at an electron density of 1 × 10 ¹¹ cm ⁻³ or more and an electron temperature of plasma of 1.5 eV or less. More specifically, the electron density is 1 × 10 ¹¹ cm ^{−3 to} 1 × 10 ¹³ cm ⁻³ and the electron temperature of plasma is 0.5 eV to 1.5 eV. Since the electron density of the plasma is high and the electron temperature in the vicinity of the object to be processed (here, the semiconductor film 223) formed on the substrate 201 is low, damage to the object to be processed can be prevented. . In addition, since the electron density of plasma is as high as 1 × 10 ¹¹ cm ⁻³ or higher, an oxide film or a nitride film formed by oxidizing or nitriding an object to be irradiated using plasma treatment is a CVD method Compared with a film formed by sputtering or the like, a film having excellent uniformity in film thickness and the like can be formed. In addition, since the electron temperature of plasma is as low as 1.5 eV or less, oxidation or nitridation can be performed at a lower temperature than conventional plasma treatment or thermal oxidation. For example, even if the plasma treatment is performed at a temperature lower than 100 degrees below the strain point of the glass substrate, the oxidation or nitridation treatment can be sufficiently performed. As a frequency for forming plasma, a high frequency such as a microwave (2.45 GHz) can be used. By forming the gate insulating film 224 by oxidizing or nitriding the surface of the semiconductor film 223 by high-density plasma treatment, the density of defect states serving as traps for electrons and holes can be reduced. Further, disconnection or the like of the gate insulating film 224 can be reduced also at the end portion of the semiconductor film 223.

Note that a low-concentration impurity element may be introduced into the semiconductor film 223 in advance in order to control a threshold value or the like. In this case, the impurity element is also introduced into a region to be a channel formation region in the semiconductor film 223 later. As the impurity element, an impurity element imparting n-type conductivity or an impurity element imparting p-type conductivity can be used. As the impurity element exhibiting n-type, phosphorus (P), arsenic (As), or the like can be used. As the p-type impurity element, boron (B), aluminum (Al), gallium (Ga), or the like can be used. Here, boron (B) is introduced in advance over the entire surface of the semiconductor film 223 so as to be contained at a concentration of 5 × 10 ^{15 to} 5 × 10 ¹⁷ / cm ³ as an impurity element.

  The first conductive film 225 is selected from tantalum (Ta), tungsten (W), titanium (Ti), molybdenum (Mo), aluminum (Al), copper (Cu), chromium (Cr), niobium (Nb), and the like. Or a single layer or a laminated structure of an alloy material or a compound material containing these elements as main components. Alternatively, a semiconductor material typified by polycrystalline silicon doped with an impurity element such as phosphorus can be used. Alternatively, tantalum nitride, tungsten nitride, molybdenum nitride, or the like may be used.

  Next, the stacked body 220 in which the semiconductor film 223, the gate insulating film 224, and the conductive film 225 are sequentially stacked is selectively removed by etching, whereby island-shaped stacked bodies 230a and 230b are formed (see FIG. 2 (B), FIG. 4 (B)). The stacked body 230a has a structure in which the semiconductor film 203, the gate insulating film 234, and the first conductive film 235 are sequentially stacked. The stacked body 230b includes the semiconductor film 213, the gate insulating film 244, and the first conductive film 245. Are stacked in order.

  Next, an insulating film 217 is formed so as to cover the stacked bodies 230a and 230b (FIGS. 2C and 4C).

  For the insulating film 217, silicon oxide, silicon oxynitride, silicon nitride oxide, diamond-like carbon (DLC), or the like formed by a CVD method, a sputtering method, or the like can be used. Also, organic materials such as polyimide, polyamide, polyvinylphenol, benzocyclobutene, acryl, and epoxy, siloxane materials such as siloxane resins, oxazole resins, etc., formed by spin coating, droplet discharge, screen printing, etc. It can be provided in a single layer or laminated structure. Note that the siloxane material corresponds to a material including a Si—O—Si bond. Siloxane has a skeleton structure formed of a bond of silicon (Si) and oxygen (O). As a substituent, an organic group containing at least hydrogen (for example, an alkyl group or an aromatic hydrocarbon) is used. A fluoro group can also be used as a substituent. Alternatively, an organic group containing at least hydrogen and a fluoro group may be used as a substituent. The oxazole resin is, for example, photosensitive polybenzoxazole. Photosensitive polybenzoxazole has a low dielectric constant (dielectric constant 2.9 at room temperature of 1 MHz) and high heat resistance (simultaneous differential thermothermal weight measurement (TG / DTA)) at a temperature rise of 5 ° C. / It is a material having a thermal decomposition temperature of 550 ° C. for min and a low water absorption (0.3% at room temperature for 24 hours). Oxazole resin has a low relative dielectric constant (about 2.9) compared to the relative dielectric constant (about 3.2 to 3.4) of polyimide, etc., so that the generation of parasitic capacitance is suppressed and high speed operation is performed. Can do. Here, as the insulating film 217, a single layer or a stack of silicon oxide, silicon oxynitride (SiOxNy) (x> y> 0), or silicon nitride oxide (SiNxOy) (x> y> 0) formed by a CVD method is used. Form. Further, an organic material such as polyimide, polyamide, polyvinylphenol, benzocyclobutene, acrylic, or epoxy, a siloxane material such as a siloxane resin, or an oxazole resin may be stacked.

  Next, the insulating film 217 is selectively removed to leave a part thereof, so that the surfaces of the first conductive films 235 and 245 are exposed (FIGS. 2D and 4D). Note that here, the remaining insulating film 217 is represented as an insulating film 207. The insulating film 217 is removed so that the surfaces of the first conductive films 235 and 245 are exposed. Preferably, the height of the surface of the first conductive films 235 and 245 and the surface of the remaining insulating film 207 are the same. Provide to do. In such a case, when the second conductive film 216 to be formed later crosses the stacked bodies 230a and 230b, the disconnection of the second conductive film 216 at the ends of the stacked bodies 230a and 230b is suppressed. be able to.

  The removal of the insulating film 217 can be performed by dry etching or wet etching. When the surface of the insulating film 217 is uneven, an organic material such as a resist, polyimide, polyamide, polyvinylphenol, benzocyclobutene, acrylic, epoxy, or the like is formed on the surface of the insulating film 217 in advance by a spin coating method or the like. The surface height of the first conductive films 235 and 245 and the surface height of the insulating film 207 are made uniform by performing etching after forming a siloxane material such as siloxane resin, oxazole resin or the like to make the surface flat. Is possible. In this case, a material formed on the surface of the insulating film 217 is preferably a material having an etching selectivity equal to that of the insulating film 217 with respect to the etching agent used.

  Alternatively, the insulating film 217 may be removed by grinding treatment, polishing treatment, CMP (Chemical Mechanical Polishing), or the like. In the grinding process, the surface of the object to be processed (here, the insulating film 217) is removed by using the grindstone particles to expose the surfaces of the first conductive films 235 and 245. In the polishing treatment, the surface of the object to be processed is shaved by a plastic smoothing action or a frictional polishing action using an abrasive such as abrasive cloth or abrasive grains.

  Note that when the insulating film 217 is removed, the first conductive films 235 and 245 function as stoppers, so that the gate insulating films 234 and 244 can be prevented from being etched. In particular, when the gate insulating films 234 and 244 and the insulating film 217 are provided with the same material, the first conductive films 235 and 245 effectively function as a stopper for etching or the like.

  The insulating film 217 is preferably removed so that the entire surfaces of the first conductive films 235 and 245 are exposed; however, the insulating film 217 is removed so that at least a part of the surfaces of the first conductive films 235 and 245 is exposed. do it. This is because when at least part of the first conductive films 235 and 245 is exposed, the second conductive film 216 formed later can be electrically connected.

  Note that although it is preferable that the surfaces of the first conductive films 235 and 245 and the surface of the insulating film 207 be completely coincident with each other, the height of the surface of the first conductive films 235 and 245 and the surface of the insulating film 207 is If the difference is smaller than the height value of the stacked bodies 230a and 230b, the surface height of the insulating film 207 may be lower than that of the first conductive films 235 and 245 or higher. May be. Even in such a case, steps at the end portions of the stacked bodies 230a and 230b can be reduced.

  Next, a second conductive film 216 is formed over the first conductive films 235 and 245 and the insulating film 207 (FIGS. 2E and 4E).

  The second conductive film 216 is selected from tantalum (Ta), tungsten (W), titanium (Ti), molybdenum (Mo), aluminum (Al), copper (Cu), chromium (Cr), niobium (Nb), and the like. Or a single layer or a laminated structure of an alloy material or a compound material containing these elements as main components. Alternatively, a semiconductor material typified by polycrystalline silicon doped with an impurity element such as phosphorus can be used. In addition, the first conductive films 235 and 245 and the second conductive film 216 may be provided using the same material or different materials. For example, tantalum nitride can be used for the first conductive films 235 and 245 and tungsten can be used for the second conductive film 216. Alternatively, a structure in which titanium is used for the first conductive films 235 and 245 and aluminum and titanium are sequentially stacked as the second conductive film 216 may be used.

  Next, a resist 211 is selectively formed over the second conductive film 216, and part of the first conductive films 235 and 245 and part of the second conductive film 216 are selected using the resist 211 as a mask. Thus, the first conductive films 205 and 215 and the second conductive film 206 are formed (FIGS. 3A and 5A). Note that at this time, part of the gate insulating films 204 and 214 (portions not covered with the resist 211) is also selectively formed using the resist 211 as a mask, similarly to the first conductive films 235 and 245 and the second conductive film 216. May be removed.

  Next, an impurity element 203 b is formed in the semiconductor film 203 by introducing an impurity element into the semiconductor films 203 and 213 using the first conductive films 205 and 215 and the second conductive film 206 as masks, and the semiconductor film 213. An impurity region 213b is formed in the substrate (FIG. 3B). The impurity region 203b functions as a source region or a drain region in the thin film transistor 200a, and the impurity region 213b functions as a source region or a drain region in the thin film transistor 200b.

As the impurity element, an impurity element imparting n-type conductivity or an impurity element imparting p-type conductivity can be used. As the impurity element exhibiting n-type, phosphorus (P), arsenic (As), or the like can be used. As the p-type impurity element, boron (B), aluminum (Al), gallium (Ga), or the like can be used. For example, phosphorus (P) is introduced into the semiconductor film 203 so as to be contained at a concentration of 1 × 10 ¹⁹ to 1 × 10 ²⁰ / cm ³ , thereby forming an n-type impurity region 203 b, and boron in the semiconductor film 213. By introducing (B) so as to be included at a concentration of 1 × 10 ¹⁹ to 1 × 10 ²⁰ / cm ³ , an impurity region 213b showing a p-type can be formed.

  Next, an insulating film 208 is formed so as to cover the second conductive film 206, the gate insulating films 204 and 214, and the conductive film 209 functioning as a source electrode or a drain electrode is selectively formed over the insulating film 208. (FIG. 3C, FIG. 5B). The conductive film 209 is provided so as to be electrically connected to the impurity regions 203b and 213b functioning as a source region or a drain region of the semiconductor films 203 and 213.

  As the insulating film 208, silicon oxide, silicon oxynitride (SiOxNy) (x> y> 0), silicon nitride oxide (SiNxOy) (x> y> 0), or the like formed by a CVD method, a sputtering method, or the like is used. it can. Alternatively, a single layer or a stacked structure including an organic material such as polyimide, polyamide, polyvinylphenol, benzocyclobutene, acrylic, or epoxy, a siloxane material such as a siloxane resin, or an oxazole resin can be used. Here, as the insulating film 208, a single layer or a stack of silicon oxide, silicon oxynitride (SiOxNy) (x> y> 0), or silicon nitride oxide (SiNxOy) (x> y> 0) formed by a CVD method is used. Form. Further, an organic material such as polyimide, polyamide, polyvinylphenol, benzocyclobutene, acrylic, or epoxy, a siloxane material such as a siloxane resin, or an oxazole resin may be stacked.

  The conductive film 209 can have a single-layer structure or a stacked structure formed using one kind of element selected from aluminum, tungsten, titanium, tantalum, molybdenum, nickel, and neodymium, or an alloy containing a plurality of such elements. For example, the conductive film formed using an alloy containing a plurality of the elements can be formed using an aluminum alloy containing titanium, an aluminum alloy containing neodymium, or the like. In the case of providing a stacked structure, for example, an aluminum layer or an aluminum alloy layer as described above may be stacked between titanium layers.

  Through the above steps, the semiconductor device illustrated in FIG. 1 can be manufactured. Note that the semiconductor device illustrated in FIG. 1 illustrates the case where part of the gate insulating film 204 is removed using the resist 211 as a mask in FIG.

  Note that although an example in which a thin film transistor is used as a transistor is described in this embodiment mode, the present invention is not limited to this, and various types of transistors can be applied. Thus, there is no limitation on the type of applicable transistor. Therefore, the invention is not limited to a thin film transistor (TFT) using a non-single crystal semiconductor film typified by amorphous silicon or polycrystalline silicon, but a transistor, a MOS transistor, or a junction transistor formed using a semiconductor substrate or an SOI substrate. Alternatively, a bipolar transistor, a transistor using a compound semiconductor such as ZnO or a-InGaZnO, a transistor using an organic semiconductor or a carbon nanotube, or another transistor can be used. Note that the non-single-crystal semiconductor film may contain hydrogen or halogen.

  In addition, the structure of the transistor can take a variety of forms. It is not limited to a specific configuration. For example, a multi-gate structure having two or more gates may be used. With the multi-gate structure, the off-current is reduced, the reliability is improved by improving the withstand voltage of the transistor, and the drain-source current does not change even when the drain-source voltage changes when operating in the saturation region. It does not change so much and can be made flat. There may also be an LDD region. By providing the LDD region, the off-current is reduced, the reliability is improved by improving the withstand voltage of the transistor, and even if the drain-source voltage changes when operating in the saturation region, the drain-source current is not much. It can be made flat without changing.

  Note that this embodiment can be freely combined with the structure of the semiconductor device described in any of the other embodiments in this specification.

(Embodiment 2)
In this embodiment, a semiconductor device and a manufacturing method thereof which are different from those in the above embodiment will be described with reference to drawings. Specifically, a structure in which the sidewall is provided in the semiconductor device described in the above embodiment is described.

A method for manufacturing a semiconductor device in the case where an insulating film (hereinafter referred to as a “side wall”) is provided for the thin film transistor described in any of the above embodiments is described with reference to FIGS. FIG. 6 shows a cross-sectional view taken along line a ₁ -b ₁ in FIG.

3A and 5A, an impurity element is introduced into the semiconductor films 203 and 213 using the second conductive film 206 as a mask to form an impurity region 212 (see FIG. 3A). FIG. 6 (A)). As the impurity element, an impurity element imparting n-type conductivity or an impurity element imparting p-type conductivity can be used. As the impurity element exhibiting n-type, phosphorus (P), arsenic (As), or the like can be used. As the p-type impurity element, boron (B), aluminum (Al), gallium (Ga), or the like can be used. Here, phosphorus (P) is introduced into the semiconductor films 203 and 213 so as to be contained at a concentration of 1 × 10 ¹⁵ to 1 × 10 ¹⁹ / cm ³ , whereby the n-type impurity region 212 is formed.

Next, a resist 221 is formed so as to cover the semiconductor film 203, and an impurity region 213b is formed by introducing an impurity element into the semiconductor film 213 using the second conductive film 206 as a mask (FIG. 6B). As the impurity element, an impurity element imparting n-type or p-type impurity element having a higher concentration than the impurity element introduced in FIG. 6A can be used. Here, by introducing boron (B) into the semiconductor film 213 at a concentration of 1 × 10 ¹⁹ to 1 × 10 ²⁰ / cm ³ , the impurity region 213 b exhibiting a p-type can be formed. As a result, a channel formation region 213a and an impurity region 213b functioning as a source region or a drain region are formed in the semiconductor film 213.

  Next, an insulating film (sidewall 218) is formed so as to be in contact with the side surfaces of the first conductive films 205 and 215 and the second conductive film 206 (FIG. 6C).

  As a method for manufacturing the sidewall 218, first, silicon, a silicon oxide, or a silicon nitride is formed by a plasma CVD method, a sputtering method, or the like so as to cover the gate insulating films 204 and 214 and the second conductive film 206. A film containing an inorganic material or a film containing an organic material such as an organic resin is formed as a single layer or a stacked layer. Next, the insulating film is selectively etched by anisotropic etching mainly in the vertical direction, whereby the sidewalls 218 in contact with the side surfaces of the first conductive films 205 and 215 and the second conductive film 206 are formed. To do. Note that part of the gate insulating films 204 and 214 and part of the insulating film 207 may be etched and removed at the same time as the sidewall 218 is formed (see FIG. 6C). By removing a part of the gate insulating films 204 and 214, the remaining gate insulating films 204 and 214 are formed below the first conductive films 205 and 215 and the sidewalls 218. Further, by removing part of the insulating film 207, the remaining insulating film 207 is formed below the second conductive film 206 and below the sidewalls 218.

Next, a resist 231 is formed so as to cover the semiconductor film 213, and an impurity element 203b is formed by introducing an impurity element into the semiconductor film 203 using the second conductive film 206 and the sidewall 218 as a mask (FIG. 6 ( D)). As the impurity element, an impurity element imparting n-type or p-type impurity element having a higher concentration than the impurity element introduced in FIG. 6A can be used. Here, by introducing phosphorus (P) into the semiconductor film 203 at a concentration of 1 × 10 ¹⁹ to 1 × 10 ²⁰ / cm ³ , the n-type impurity region 203b can be formed. As a result, a channel formation region 203a, an impurity region 203b that functions as a source region or a drain region, and an impurity region 203c that functions as an LDD region are formed in the semiconductor film 203.

  Next, an insulating film 208 is formed so as to cover the second conductive film 206, the gate insulating films 204 and 214, the sidewalls 218, and the like, and a conductive film 209 functioning as a source electrode or a drain electrode is formed over the insulating film 208. It is selectively formed (FIG. 6E). The conductive film 209 is provided so as to be electrically connected to the impurity regions 203b and 213b functioning as a source region or a drain region of the semiconductor films 203 and 213.

  Through the above steps, a semiconductor device provided with a sidewall can be manufactured.

  Note that in this embodiment mode, an LDD region is formed in the semiconductor film 203 included in the n-type thin film transistor 200a, and an LDD region is not intentionally provided in the semiconductor film 213 included in the p-type thin film transistor 200b. However, the present invention is not limited to this, and an LDD region may be formed in both the semiconductor film 203 and the semiconductor film 213.

  Note that this embodiment can be freely combined with any of the other embodiments in this specification.

(Embodiment 3)
In this embodiment, a semiconductor device and a manufacturing method thereof which are different from those in the above embodiment will be described with reference to drawings. Specifically, in the semiconductor device described in any of the above embodiments, an impurity having a conductivity type different from that of the impurity region serving as the source region or the drain region adjacent to the impurity region functioning as the source region or the drain region in the semiconductor film. A configuration provided with regions will be described.

An example of the semiconductor device described in this embodiment will be described with reference to FIGS. 7A is a top view of the semiconductor device described in this embodiment. FIG. 7B is a cross-sectional view taken along line a ₁ -b ₁ in FIG. 7A, and FIG. 7A is a _{2 in} FIG. A cross-sectional view at -b ₂ is shown in FIG.

  In the semiconductor device described in this embodiment, impurity regions 203d and 213d are provided in end portions of the semiconductor films 203 and 213 in the structure illustrated in FIG. The impurity regions 203d and 213d may be provided at and / or in the vicinity of the semiconductor films 203 and 213 that overlap with the second conductive film 206 functioning as a gate electrode and a gate wiring. The impurity regions 203d and 213d are provided so as to have different conductivity types from the impurity regions 203b and 213b functioning as a source region or a drain region in the semiconductor films 203 and 213.

  For example, in the semiconductor film 203, when the impurity region 203b functioning as a source region or a drain region is provided to have an n-type conductivity type, the impurity region 203d provided at the end portion of the semiconductor film 203 has a p-type conductivity type. Provide to have. In addition, in the semiconductor film 213, when the impurity region 213b functioning as a source region or a drain region is provided so as to have p-type conductivity, the impurity region 213d provided at the end portion of the semiconductor film 213 has n-type conductivity. Provide to have. In this case, the impurity regions 203d and 213d may be provided in one of the semiconductor films 203 and 213, or may be provided in both.

  Note that the end portions of the semiconductor films 203 and 213 that overlap with the second conductive film 206 and / or the vicinity thereof are the end portions of the semiconductor films 203 and 213 and the regions that overlap with the second conductive film 206 and the overlapping regions. The vicinity of the semiconductor film 203 or 213 and the vicinity of the region overlapping with the second conductive film 206 (the region overlapping with the second conductive film 206 is not included). For example, in the case where the impurity regions 203d and 213d are formed at the end portions of the semiconductor films 203 and 213 and in the vicinity of the region overlapping with the second conductive film 206, before the first conductive film 205 is formed. It is preferable to introduce an impurity element into the semiconductor films 203 and 213. On the other hand, in the case where the impurity regions 203d and 213d are formed in the vicinity of the region overlapping with the second conductive film 206 at the end portions of the semiconductor films 203 and 213, the semiconductor film 203 is formed after the second conductive film 206 is formed. An impurity element can be introduced into 213.

  As described above, the impurity regions 203b and 213b and the impurity region 203d are provided at the end portions of the semiconductor films 203 and 213 overlapping the second conductive film 206 by providing the impurity regions 203d and 213d having different conductivity types from the impurity regions 203b and 213b. The adjacent portion of 213d has a high resistance due to the pn junction. As a result, the influence of the characteristics of the channel formation region formed in the end portions of the semiconductor films 203 and 213 overlapping with the second conductive film 206 on the characteristics of the entire transistor can be reduced.

  In a conventional thin film transistor, charge may be accumulated in the end portion of the semiconductor film overlapping with the conductive film due to a poor coating of the gate insulating film or a manufacturing process. A transistor 151 (hereinafter also referred to as “edge transistor 151”) having an end portion of the semiconductor films 203 and 213 as a channel formation region and a transistor 152 (hereinafter referred to as “main transistor”) having a central portion of the semiconductor films 203 and 213 as a channel formation region. 152 ”(also referred to as“ 152 ”) can be regarded as one transistor connected in parallel. Accordingly, the equivalent circuit is as shown in FIG. 8A, and the characteristics of the entire transistor (edge transistor 151 + main transistor 152) may affect not only the characteristics of the main transistor 152 but also the characteristics of the edge transistor 151.

  On the other hand, the structure shown in this embodiment mode can also be regarded as a structure in which the main transistor 152 and the edge transistor 151 are connected in parallel. However, by providing the impurity regions 203d and 213d, an equivalent circuit is shown in FIG. ) As shown. Since the resistance between the impurity regions 203b and 213b and the impurity regions 203d and 213d is increased, the influence of the characteristics of the edge transistor 151 on the characteristics of the entire transistor can be reduced.

  In particular, in the semiconductor device of the present invention, the surface of the remaining insulating film 207 is removed when part of the insulating film 217 is removed in order to expose the surfaces of the first conductive films 235 and 245 after the insulating film 217 is formed. May be formed lower than the height of the surface of the gate insulating films 204 and 214. In this case, since the second conductive film 216 formed thereafter is in contact with the side surfaces of the first conductive films 205 and 215 and the gate insulating films 204 and 214, the semiconductor films 203 and 213 and the second conductive film 216 There is a risk of short circuiting. Even in such a case, by using the structure described in this embodiment mode, problems such as a short circuit in the end portions of the semiconductor films 203 and 213 can be suppressed.

  Note that this embodiment can be freely combined with any of the other embodiments in this specification. For example, the sidewall described in Embodiment 2 can be provided in the structure described in this embodiment.

(Embodiment 4)
In this embodiment, a semiconductor device and a manufacturing method thereof which are different from those in the above embodiment will be described with reference to drawings. Specifically, a nonvolatile memory element that forms a memory portion and an element such as a transistor that controls the memory element in a semiconductor device will be described.

  First, an example of a memory portion provided in the semiconductor device is illustrated in FIG.

  The memory portion illustrated in FIG. 9 includes a plurality of memory cells each including a control transistor S and a nonvolatile memory element M. In FIG. 9, one memory cell is formed by the control transistor S01 and the nonvolatile memory element M01. Similarly, the control transistor S02 and the nonvolatile memory element M02, the control transistor S03 and the nonvolatile memory element M03, the control transistor S11 and the nonvolatile memory element M11, the control transistor S12 and the nonvolatile memory element M12, the control A memory cell is formed by the transistor S13 and the nonvolatile memory element M13.

  The gate electrode of the control transistor S01 is connected to the word line WL1, one of the source and the drain is connected to the bit line BL0, and the other is connected to the source or the drain of the nonvolatile memory element M01. The gate electrode of the nonvolatile memory element M01 is connected to the word line WL11, one of the source and the drain is connected to the source or the drain of the control transistor S01, and the other is connected to the source line SL0.

  Further, the nonvolatile memory element provided in the memory portion may be provided as a NAND type as shown in FIG.

  In the equivalent circuit of the NAND memory cell array shown in FIG. 22, a NAND cell NS1 in which a plurality of nonvolatile memory elements are connected in series is connected to the bit line BL. A plurality of NAND cells gather to constitute a block BLK. The block BLK1 shown in FIG. 22 has 32 word lines (word lines WL0 to WL31). The nonvolatile memory elements located in the same row of the block BLK1 are commonly connected to word lines corresponding to this row.

  In this case, since the select transistors S1 and S2 and the nonvolatile memory elements M0 to M31 are connected in series, these may be formed as a single semiconductor layer 34. Accordingly, wiring for connecting the nonvolatile memory elements can be omitted, so that integration can be achieved. Further, it is possible to easily separate the adjacent NAND cells. Further, the semiconductor layer 36 of the select transistors S1 and S2 and the semiconductor layer 38 of the NAND cell may be formed separately. When performing an erasing operation for extracting charges from the floating gates of the nonvolatile memory elements M0 to M31, the erasing operation can be performed in units of the NAND cells. Further, the nonvolatile memory elements (for example, the row of M30) commonly connected to one word line may be formed by one semiconductor layer 40.

  In addition, a nonvolatile memory element provided in the memory portion may be provided as an AND type as shown in FIG.

  In the equivalent circuit of the AND memory cell array shown in FIG. 23, an AND cell AS1 in which a plurality of nonvolatile memory elements are connected in parallel is connected to the bit line BL. A plurality of AND cells constitute a block BLK. The number of word lines in the block BLK1 shown in FIG. 23 is 128 (word lines WL0 to WL127). The nonvolatile memory elements located in the same row of the block BLK1 are commonly connected to word lines corresponding to this row.

  In this case, the selection transistors S1 and S2 and the nonvolatile memory elements M0 to M128 are connected in parallel. Specifically, a main bit line BL and a sub-bit line BL ′ are provided, and an array structure in which each nonvolatile memory element is connected in parallel to the sub-bit line BL ′ allows each word line WL to have a structure. Erasing is possible.

  An advantage of the NAND type is miniaturization of memory cells, and an advantage of the AND type is that multi-value technology can be easily introduced. Needless to say, the nonvolatile memory element provided in the memory portion described in this embodiment may be provided in a NAND type or an AND type.

  Next, a case where a nonvolatile memory element and a thin film transistor are formed at the same time will be described with reference to the drawings. 12 to 14 are top views, and FIGS. 10, 11, and 20 are cross-sectional views taken along lines AB and CD in FIGS. FIG. 21 is a cross-sectional view taken along lines EF and GH in FIG. Note that this embodiment mode shows the case where charge accumulation of the nonvolatile memory element between A and B is performed by electrons, and the case where the thin film transistor provided between C and D is an n-channel type will be described. It is not limited to this.

  First, the semiconductor film 303 is formed over the substrate 301 with the insulating film 302 interposed therebetween, and the first insulating film 304 and the charge storage layer 305 are stacked over the semiconductor film 303 (see FIG. 10A). .

  The substrate 301 is selected from a semiconductor substrate such as a glass substrate, a quartz substrate, a ceramic substrate, a metal substrate (for example, a stainless steel substrate), and a Si substrate. In addition, a substrate such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), or acrylic can be selected as the plastic substrate.

  The insulating film 302 is formed using silicon oxide, silicon nitride, silicon oxynitride (SiOxNy) (x> y> 0), silicon nitride oxide (SiNxOy) (x> y> 0), or the like using a CVD method, a sputtering method, or the like. It is formed using an insulating material. For example, in the case where the insulating film 302 has a two-layer structure, a silicon nitride oxide film may be formed as the first insulating film and a silicon oxynitride film may be formed as the second insulating film. Alternatively, a silicon nitride film may be formed as the first insulating film, and a silicon oxide film may be formed as the second insulating film. In this manner, by forming the insulating film 302 functioning as a blocking layer, alkali metal such as Na or alkaline earth metal from the substrate 301 can be prevented from adversely affecting the element formed thereon. Note that the insulating film 302 may be omitted when quartz is used for the substrate 301.

  The semiconductor film 303 is formed using an amorphous semiconductor film or a crystalline semiconductor film. The crystalline semiconductor film is obtained by crystallizing an amorphous semiconductor film formed over the insulating film 302 by heat treatment or laser light irradiation, or after amorphizing the crystalline semiconductor film formed over the insulating film 302. , Recrystallized materials, and the like. Crystallization by laser light irradiation may be performed as described in Embodiment Mode 1.

  The first insulating film 304 can be formed by performing heat treatment, plasma treatment, or the like on the semiconductor film 303. For example, by performing oxidation treatment, nitridation treatment, or oxynitride treatment on the semiconductor film 303 by high-density plasma treatment, the first insulating film 304 that becomes an oxide film, a nitride film, or an oxynitride film on the semiconductor film 303, respectively. Form. Note that the first insulating film 304 may be formed using silicon oxide, silicon nitride, silicon oxynitride, silicon nitride oxide, or the like by a CVD method or a sputtering method, or may be formed using these films formed by a CVD method or a sputtering method. You may form by performing high-density plasma processing.

  For example, when the semiconductor film 303 is oxidized or nitrided by high-density plasma treatment using a material containing Si as a main component, a silicon oxide (SiOx) film or silicon nitride (SiNx) is used as the first insulating film 304. A film is formed. Further, after the semiconductor film 303 is oxidized by high-density plasma treatment, nitriding treatment may be performed by performing high-density plasma treatment again. In this case, a silicon oxide film is formed in contact with the semiconductor film 303, and a nitrogen plasma treatment layer having a high nitrogen concentration is provided on or near the surface of the silicon oxide film.

  Here, the first insulating film 304 is formed with a thickness of 1 to 10 nm, preferably 1 to 5 nm. For example, the semiconductor film 303 is oxidized by high-density plasma treatment to form a silicon oxide film with a thickness of about 3 nm on the surface of the semiconductor film 303, and then nitrided by high-density plasma treatment to be near or near the surface of the silicon oxide film. A nitrogen plasma treatment layer is formed. By performing high-density plasma treatment on the semiconductor film 303 in order under an oxygen atmosphere and a nitrogen atmosphere, the first insulating film 304 is a silicon oxide layer of approximately 3 nm and a depth of 0.25 to 0.75 nm from the surface. Furthermore, it can be set as the structure which contained nitrogen in the ratio of 20-50 atomic%. Note that the nitrogen plasma treatment layer contains silicon (silicon oxynitride) containing oxygen and nitrogen.

  At this time, it is preferable that the oxidation treatment and the nitriding treatment by the high-density plasma treatment are continuously performed without being exposed to the atmosphere. By continuously performing the high-density plasma treatment, it is possible to prevent contamination from entering and improve production efficiency.

Note that in the case of oxidizing a semiconductor film by high-density plasma treatment, an atmosphere containing oxygen (for example, oxygen (O ₂ ) or dinitrogen monoxide (N ₂ O) and a rare gas (He, Ne, Ar, Kr) , Xe), or an atmosphere of oxygen or dinitrogen monoxide and hydrogen (H ₂ ) and a rare gas atmosphere). On the other hand, when a semiconductor film is nitrided by high-density plasma treatment, an atmosphere containing nitrogen (for example, an atmosphere containing nitrogen (N ₂ ) and a rare gas (containing at least one of He, Ne, Ar, Kr, and Xe)) And high density plasma treatment under nitrogen, hydrogen, and rare gas atmosphere, or NH ₃ and rare gas atmosphere.

  As the rare gas, for example, Ar can be used. A gas in which Ar and Kr are mixed may be used. In the case where the high-density plasma treatment is performed in a rare gas atmosphere, the first insulating film 304 contains a rare gas (including at least one of He, Ne, Ar, Kr, and Xe) used for the plasma treatment. In some cases, when Ar is used, the first insulating film 304 may contain Ar.

Further, the conditions for the high-density plasma treatment may be performed under the conditions described in the above embodiment mode. In this embodiment, when an object to be processed is oxidized by high-density plasma treatment, a mixed gas of oxygen (O ₂ ), hydrogen (H ₂ ), and argon (Ar) is introduced. The mixed gas used here may be introduced with 0.1 to 100 sccm of oxygen, 0.1 to 100 sccm of hydrogen, and 100 to 5000 sccm of argon. Note that the mixed gas is preferably introduced at a ratio of oxygen: hydrogen: argon = 1: 1: 100. For example, oxygen may be introduced at 5 sccm, hydrogen at 5 sccm, and argon at 500 sccm.

In addition, when performing nitriding treatment by high-density plasma treatment, a mixed gas of nitrogen (N ₂ ) and argon (Ar) is introduced. The mixed gas used here may be introduced at 20 to 2000 sccm of nitrogen and 100 to 10,000 sccm of argon. For example, nitrogen may be introduced at 200 sccm and argon at 1000 sccm.

  In this embodiment mode, the first insulating film 304 formed over the semiconductor film 303 provided in the memory portion functions as a tunnel oxide film in a nonvolatile memory element completed later. Therefore, the thinner the first insulating film 304 is, the easier it is for the tunnel current to flow, and the memory element can operate at high speed. Further, as the first insulating film 304 is thinner, charges can be stored in the charge storage layer 305 at a lower voltage, so that power consumption of the semiconductor device can be reduced. Therefore, the first insulating film 304 is preferably formed thin (for example, 10 nm or less).

  In general, there is a thermal oxidation method as a method for forming a thin insulating film over a semiconductor film. However, when a substrate having a sufficiently low melting point, such as a glass substrate, is used as the substrate 301, the thermal oxidation method is used. It is very difficult to form one insulating film 304. In addition, an insulating film formed by a CVD method or a sputtering method includes defects inside the film, so that the film quality is not sufficient, and there is a problem that defects such as pinholes occur when the film thickness is thin. Further, in the case where an insulating film is formed by a CVD method or a sputtering method, the end portion of the semiconductor film is not sufficiently covered, and the conductive film and the like that are formed later on the first insulating film 304 and the semiconductor film leak. There is a case. Therefore, as shown in this embodiment mode, by forming the first insulating film 304 by high-density plasma treatment, an insulating film denser than an insulating film formed by a CVD method, a sputtering method, or the like can be formed. . As a result, high-speed operation and charge retention characteristics as a memory can be improved. Note that in the case where the first insulating film 304 is formed by a CVD method or a sputtering method, after the insulating film is formed, high-density plasma treatment is performed, and oxidation, nitridation, or oxynitridation is performed on the surface of the insulating film. Preferably, for example, after silicon oxynitride is formed by a CVD method, oxidation treatment is performed using high-density plasma treatment, and then nitriding treatment is performed.

The charge storage layer 305 can be formed using a conductive film, a semiconductor film, an insulating film having a defect that traps charges in the film, an insulating film containing conductive particles or semiconductor particles such as silicon. For example, the charge storage layer 305 can be formed using a film containing silicon (Si) as a main component. Alternatively, a film containing germanium such as germanium (Ge) or a silicon germanium alloy can be used. Here, as the charge storage layer 305, a film containing germanium as a main component is formed with a thickness of 1 to 20 nm, preferably 5 to 10 nm, by performing a plasma CVD method in an atmosphere containing a germanium element (for example, GeH ₄ ). . In this case, germanium having a smaller energy gap than Si is formed as the semiconductor film 303 using a material containing Si as a main component and the first insulating film 304 functioning as a tunnel oxide film is formed over the semiconductor film 303. Is provided as the charge storage layer 305, the second barrier formed by the insulating film for the charge of the charge storage layer 305 is different from the first barrier formed by the insulating film for the charge of the semiconductor film 303. Increases energy. As a result, charge can be easily injected from the semiconductor film 303 into the charge storage layer 305, and the charge can be prevented from disappearing from the charge storage layer 305. That is, when operating as a memory, high-efficiency writing can be performed at a low voltage, and charge retention characteristics can be improved. In addition, the charge storage layer 305 formed over the semiconductor film 303 provided in the memory portion functions as a floating gate in a nonvolatile memory element completed later.

  As the charge storage layer 305, an insulating film containing a nitrogen element, for example, a silicon nitride (SiNx) film, a silicon nitride oxide (SiNxOy) (x> y) film, a silicon oxynitride (SiOxNy) (x> y) film, or You may form with the film | membrane in which electroconductive particle and semiconductor particle were contained in these insulating films. For example, a silicon nitride film having defects that trap charges in the film can be formed with a thickness of 1 to 20 nm, preferably 1 to 10 nm.

  Next, the charge storage layer 305 is selectively removed to form the charge storage layer 306 (see FIG. 10B). Here, the charge accumulation layer 305 is removed so as to remain above the semiconductor film 303 included in the nonvolatile memory element to be completed later.

  Next, by selectively removing the first insulating film 304 and the semiconductor film 303, a stacked body 307 in which the semiconductor film 307a, the first insulating film 307b, and the charge storage layer 307c are sequentially stacked; A semiconductor film 308 is formed (see FIG. 10C).

  Next, a second insulating film 309 is formed so as to cover the stacked body 307 and the semiconductor film 308 (see FIG. 10D).

  As the second insulating film 309, silicon oxide, silicon oxynitride, silicon nitride oxide, diamond-like carbon (DLC), or the like formed by a CVD method, a sputtering method, or the like can be used. Also, organic materials such as polyimide, polyamide, polyvinylphenol, benzocyclobutene, acryl, and epoxy, siloxane materials such as siloxane resins, oxazole resins, etc., formed by spin coating, droplet discharge, screen printing, etc. It can be provided in a single layer or laminated structure.

  Next, the second insulating film 309 is selectively removed to leave a part thereof, so that the surfaces of the charge storage layer 307c and the semiconductor film 308 are exposed (FIGS. 10E and 12). Note that the remaining second insulating film 309 is represented as a second insulating film 310 here. Any of the methods described in the above embodiments can be used to remove the second insulating film 309.

  The second insulating film 309 is removed so that the surfaces of the charge storage layer 306 and the semiconductor film 308 are exposed. Preferably, the height of the surface of the semiconductor film 308 and the surface of the remaining second insulating film 310 are the same. Provide to match. In such a case, when an insulating film or a conductive film to be formed later crosses the stacked body 307 or the semiconductor film 308, the occurrence of a step breakage or the like at an end portion of the stacked body 307 or the semiconductor film 308 is suppressed. be able to.

  The second insulating film 309 is preferably removed so that the surfaces of the charge storage layer 307c and the semiconductor film 308 are exposed, but at least part of the surfaces of the charge storage layer 307c and the semiconductor film 308 are exposed. Can be removed.

  Note that although it is preferable that the surface of the semiconductor film 308 and the surface of the second insulating film 310 be completely matched, the difference in height between the surface of the semiconductor film 308 and the surface of the second insulating film 310 is the semiconductor film. The height of the surface of the second insulating film 310 may be set lower or higher than the height of the surface of the semiconductor film 308 as long as it is smaller than the height value of 308. This is because even in such a case, steps at the end portions of the stacked body 307 and the semiconductor film 308 can be reduced.

  Next, a third insulating film 311 is formed over the charge storage layer 307c, the semiconductor film 308, and the second insulating film 310 (FIG. 11A).

  The third insulating film 311 is formed as a single layer or a stacked layer using an insulating material such as silicon oxide, silicon nitride, silicon oxynitride, or silicon nitride oxide by a CVD method, a sputtering method, or the like. For example, in the case where the third insulating film 311 is provided as a single layer, a silicon oxynitride film or a silicon nitride oxide film is formed with a thickness of 5 to 50 nm by a CVD method. In the case where the third insulating film 311 is provided in a three-layer structure, a silicon oxynitride film is formed as the first insulating film, a silicon nitride film is formed as the second insulating film, and the third insulating film 311 is formed. A silicon oxynitride film is formed as the insulating film. In addition, germanium oxide or nitride may be used for the third insulating film 311.

  Alternatively, the third insulating film 311 may be provided by performing high-density plasma treatment on the insulating film formed by the above-described method. For example, the third insulating film 311 can be formed by forming a silicon oxynitride film or a silicon nitride oxide film using a CVD method and then performing oxidation treatment or nitridation treatment using high-density plasma treatment. Of course, the nitriding treatment may be performed after the oxidation treatment as described above. By performing high-density plasma treatment on the insulating film formed by a CVD method or a sputtering method, the insulating film can be made dense and the density of defect states serving as traps for electrons and holes can be reduced.

  Note that the third insulating film 311 formed above the semiconductor film 307a functions as a control insulating film in a nonvolatile memory element to be completed later, and the third insulating film 311 formed above the semiconductor film 308 is It functions as a gate insulating film in a transistor to be completed later.

  Next, a conductive film 312 is formed over the third insulating film 311 (FIG. 11B).

  The conductive film 312 is an element selected from tantalum (Ta), tungsten (W), titanium (Ti), molybdenum (Mo), aluminum (Al), copper (Cu), chromium (Cr), niobium (Nb), and the like. Alternatively, a single layer or a stacked structure of an alloy material or a compound material containing these elements as a main component can be used. Alternatively, a metal nitride film obtained by nitriding these elements can be used. In addition, a semiconductor material typified by polycrystalline silicon doped with an impurity element such as phosphorus can be used.

  Here, the conductive film 312 is provided with a structure in which tantalum nitride and tungsten are sequentially stacked. In addition, the conductive film 312 can be provided with a structure in which a metal nitride film and a metal film are sequentially stacked.

  Next, a resist 313 is selectively formed over the conductive film 312, and the conductive film 312, the third insulating film 311, the charge storage layer 307c, and the first insulating film 307b are selectively formed using the resist 313 as a mask. It is removed by etching (FIGS. 11C and 13). Here, a first insulating film 314 functioning as a tunnel insulating film, a charge storage layer 315, a third insulating film 316 functioning as a control insulating film, and a conductive film functioning as a gate electrode are formed over part of the semiconductor film 307a. 317 is left, and a third insulating film 318 functioning as a gate insulating film and a conductive film 319 functioning as a gate electrode are left over part of the semiconductor film 308.

  Next, an impurity element is introduced into the semiconductor films 307a and 308 using the conductive films 317 and 319 as masks, whereby a channel formation region 320a and an impurity region 320b functioning as a source region or a drain region are formed in the semiconductor film 307a. A channel formation region 321 a and an impurity region 321 b functioning as a source region or a drain region are formed in the film 308. Then, an insulating film 322 is formed so as to cover the conductive films 317 and 319, the semiconductor films 307a and 308, and the conductive film 323 functioning as a source electrode or a drain electrode is selectively formed over the insulating film 322 (FIG. 11 (D), FIG. 21 (A), FIG. 14).

  For the insulating film 322, silicon oxide, silicon oxynitride, silicon nitride oxide, or the like formed by a CVD method, a sputtering method, or the like can be used. Alternatively, a single layer or a stacked structure including an organic material such as polyimide, polyamide, polyvinylphenol, benzocyclobutene, acrylic, or epoxy, a siloxane material such as a siloxane resin, or an oxazole resin can be used. Note that the siloxane material corresponds to a material including a Si—O—Si bond. Siloxane has a skeleton structure formed of a bond of silicon (Si) and oxygen (O). As a substituent, an organic group containing at least hydrogen (for example, an alkyl group or an aromatic hydrocarbon) is used. A fluoro group can also be used as a substituent. Alternatively, an organic group containing at least hydrogen and a fluoro group may be used as a substituent. The oxazole resin is, for example, photosensitive polybenzoxazole. Photosensitive polybenzoxazole has a low dielectric constant (dielectric constant 2.9 at room temperature of 1 MHz) and high heat resistance (simultaneous differential thermothermal weight measurement (TG / DTA)) at a temperature rise of 5 ° C. / It is a material having a thermal decomposition temperature of 550 ° C. for min and a low water absorption (0.3% at room temperature for 24 hours). Oxazole resin has a low relative dielectric constant (about 2.9) compared to the relative dielectric constant (about 3.2 to 3.4) of polyimide, etc., so that the generation of parasitic capacitance is suppressed and high speed operation is performed. Can do. Here, as the insulating film 322, a single layer or a stack of silicon oxide, silicon oxynitride (SiOxNy) (x> y> 0), or silicon nitride oxide (SiNxOy) (x> y> 0) formed by a CVD method is used. Form. Further, an organic material such as polyimide, polyamide, polyvinylphenol, benzocyclobutene, acrylic, or epoxy, a siloxane material such as a siloxane resin, or an oxazole resin may be stacked.

  The conductive film 323 can have a single-layer structure or a stacked structure formed using one kind of element selected from aluminum, tungsten, titanium, tantalum, molybdenum, nickel, and neodymium, or an alloy containing a plurality of such elements. For example, the conductive film formed using an alloy containing a plurality of the elements can be formed using an aluminum alloy containing titanium, an aluminum alloy containing neodymium, or the like. In the case of providing a stacked structure, for example, an aluminum layer or an aluminum alloy layer as described above may be stacked between titanium layers.

  Through the above steps, a semiconductor device having a nonvolatile memory element can be manufactured. Note that as shown in Embodiment Mode 2, the nonvolatile memory element may have a structure in which sidewalls are provided so as to be in contact with the side surfaces of the conductive film 317, the third insulating film 316, the charge storage layer 315, and the like. .

  Note that in the above manufacturing process, after the insulating film 309 is formed (FIG. 10D), part of the insulating film 309 is removed so that the surface of the semiconductor film 308 is exposed, and the insulating film 310 is left. However, the insulating film 309 may be removed as shown in FIG. This will be described with reference to FIG.

  First, the structure shown in FIG. 10D is formed using the above-described method (FIG. 20A).

  Next, part of the insulating film 309 is removed so that the surface of the charge storage layer 307c is exposed, whereby the insulating film 310a is left (FIG. 20B). At this time, the insulating film 309 is removed so that the surface of the semiconductor film 308 is not exposed. Note that in this case, when the charge storage layer 307c and the insulating film 310a are provided so that the heights of the surfaces substantially coincide with each other, disconnection of the third insulating film 311 and the conductive film 312 to be formed later can be prevented. Therefore, it is preferable.

  Next, a resist 325 is formed over the charge storage layer 307c and the insulating film 310a provided in the vicinity thereof, and the insulating film 310a not covered with the resist 325 is removed so that the surface of the semiconductor film 308 is exposed. Thus, the insulating film 310b is left (FIG. 20C). Note that at this time, when the surface of the semiconductor film 308 and the surface of the insulating film 310b are provided so that the height thereof substantially matches, the third insulating film 311 and the conductive film 312 which are formed later are formed over the semiconductor film 308 and the insulating film 310b. This is preferable because a connection failure (step disconnection) caused by the step can be prevented. In addition, by changing the etching method in FIGS. 20B and 20C, damage to the semiconductor film 308 due to exposing the surface of the semiconductor film 308 when the insulating film 309 is removed can be reduced. Can do. For example, in FIG. 20B, the charge storage layer 307c functions as a stopper, and the insulating film 309 is removed by dry etching. In FIG. 20C, the surface of the semiconductor film 308 is damaged. The insulating film 310a can be removed using difficult wet etching.

  Next, a third insulating film 311 and a conductive film 312 are formed so as to cover the insulating films 310a and 310b, the charge storage layer 307c, and the semiconductor film 308 (FIG. 20D). After that, by using the above-described method, a semiconductor device having a nonvolatile memory element can be manufactured (FIG. 21B).

  As described above, the formation of the insulating films 316 and 318 in the end portion of the charge storage layer 315 and the end portion of the semiconductor film 308 in the nonvolatile memory element and the thin film transistor is performed by the method shown in FIG. It can be prevented from occurring.

  Note that this embodiment can be freely combined with any of the other embodiments in this specification.

(Embodiment 5)
In this embodiment, an example of usage of the semiconductor device described in the above embodiment is described. Specifically, application examples of a semiconductor device capable of inputting and outputting data without contact will be described below with reference to the drawings. A semiconductor device in which data can be input / output without contact is also referred to as an RFID tag, an ID tag, an IC tag, an IC chip, an RF tag, a wireless tag, an electronic tag, or a wireless chip depending on the application.

  First, an example of a top structure of the semiconductor device described in this embodiment will be described with reference to FIG. A semiconductor device 80 illustrated in FIG. 15 includes a thin film integrated circuit 131 provided with a plurality of elements such as thin film transistors included in a memory portion and a logic portion, and a conductive film 132 functioning as an antenna. The conductive film 132 functioning as an antenna is electrically connected to the thin film integrated circuit 131.

  In the case where a thin film transistor is provided in the thin film integrated circuit 131, the structure described in the above embodiment can be applied.

  FIGS. 15B and 15C are schematic views of the cross section of FIG. The conductive film 132 functioning as an antenna may be provided above the elements included in the memory portion and the logic portion. For example, the conductive film 132 functions as an antenna via the insulating film 130 above the structure described in the above embodiment mode. A conductive film 132 can be provided (FIG. 15B). Alternatively, the conductive film 132 functioning as an antenna can be provided over the substrate 133 and then attached to the thin film integrated circuit 131 (FIG. 15C). Here, the conductive film 136 provided over the insulating film 130 and the conductive film 132 functioning as an antenna are electrically connected through conductive particles 134 contained in an adhesive resin 135.

  Note that although an example in which the conductive film 132 functioning as an antenna is provided in a coil shape and an electromagnetic induction method or an electromagnetic coupling method is applied is described in this embodiment mode, the semiconductor device of the present invention is not limited thereto, and a microwave method is used. It is also possible to apply. In the case of a microwave method, the shape of the conductive film 132 functioning as an antenna may be determined as appropriate depending on the wavelength of the electromagnetic wave used.

  For example, when a microwave method (for example, UHF band (860 to 960 MHz band), 2.45 GHz band, or the like) is applied as a signal transmission method in the semiconductor device 80, the wavelength of an electromagnetic wave used for signal transmission is considered. The length of the conductive film functioning as an antenna may be set as appropriate, and the conductive film functioning as an antenna may be linear (for example, a dipole antenna (FIG. 16A)) or flat (for example, a patch). It can be formed into an antenna (FIG. 16B) or a ribbon shape (FIGS. 16C and 16D), etc. The shape of the conductive film 132 functioning as an antenna is not limited to a linear shape, In consideration of the wavelength of the electromagnetic wave, it may be provided in a curved shape, a meandering shape, or a combination thereof.

  The conductive film 132 functioning as an antenna is formed using a conductive material by a CVD method, a sputtering method, a printing method such as screen printing or gravure printing, a droplet discharge method, a dispenser method, a plating method, or the like. Conductive materials are aluminum (Al), titanium (Ti), silver (Ag), copper (Cu), gold (Au), platinum (Pt) nickel (Ni), palladium (Pd), tantalum (Ta), molybdenum An element selected from (Mo) or an alloy material or a compound material containing these elements as a main component is formed in a single layer structure or a laminated structure.

  For example, when the conductive film 132 that functions as an antenna is formed by using a screen printing method, a conductive paste in which conductive particles having a particle diameter of several nanometers to several tens of micrometers are dissolved or dispersed in an organic resin is selected. Can be provided by printing. The conductive particles include silver (Ag), gold (Au), copper (Cu), nickel (Ni), platinum (Pt), palladium (Pd), tantalum (Ta), molybdenum (Mo) and titanium (Ti). Any one or more metal particles, silver halide fine particles, or dispersible nanoparticles can be used. In addition, as the organic resin contained in the conductive paste, one or more selected from organic resins that function as a binder of metal particles, a solvent, a dispersant, and a coating material can be used. Typically, an organic resin such as an epoxy resin or a silicon resin can be given. In forming the conductive film, it is preferable to fire after extruding the conductive paste. For example, when fine particles containing silver as a main component (for example, a particle size of 1 nm or more and 100 nm or less) are used as a conductive paste material, the conductive film is obtained by being cured by baking in a temperature range of 150 to 300 ° C. Can do. Further, fine particles mainly composed of solder or lead-free solder may be used. In this case, it is preferable to use fine particles having a particle diameter of 20 μm or less. Solder and lead-free solder have the advantage of low cost.

  Next, operation of the semiconductor device described in this embodiment is described.

  The semiconductor device 80 has a function of communicating data without contact, and controls the high frequency circuit 81, the power supply circuit 82, the reset circuit 83, the clock generation circuit 84, the data demodulation circuit 85, the data modulation circuit 86, and other circuits. A control circuit 87, a memory circuit 88, and an antenna 89 are provided (FIG. 17A). The high frequency circuit 81 is a circuit that receives a signal from the antenna 89 and outputs the signal received from the data modulation circuit 86 from the antenna 89, and the power supply circuit 82 is a circuit that generates a power supply potential from the received signal, and a reset circuit 83. Is a circuit that generates a reset signal, a clock generation circuit 84 is a circuit that generates various clock signals based on the reception signal input from the antenna 89, and a data demodulation circuit 85 demodulates the reception signal to control the control circuit 87. The data modulation circuit 86 is a circuit that modulates the signal received from the control circuit 87. Further, as the control circuit 87, for example, a code extraction circuit 91, a code determination circuit 92, a CRC determination circuit 93, and an output unit circuit 94 are provided. The code extraction circuit 91 is a circuit that extracts a plurality of codes included in an instruction sent to the control circuit 87, and the code determination circuit 92 compares the extracted code with a code corresponding to a reference. The CRC determination circuit 93 is a circuit that detects the presence or absence of a transmission error or the like based on the determined code.

  Next, an example of operation of the above-described semiconductor device will be described. First, a radio signal is received by the antenna 89. The radio signal is sent to the power supply circuit 82 via the high frequency circuit 81, and a high power supply potential (hereinafter referred to as VDD) is generated. VDD is supplied to each circuit included in the semiconductor device 80. The signal sent to the data demodulation circuit 85 via the high frequency circuit 81 is demodulated (hereinafter, demodulated signal). Further, the signal and the demodulated signal that have passed through the reset circuit 83 and the clock generation circuit 84 via the high frequency circuit 81 are sent to the control circuit 87. The signal sent to the control circuit 87 is analyzed by the code extraction circuit 91, the code determination circuit 92, the CRC determination circuit 93, and the like. Then, information on the semiconductor device 80 stored in the storage circuit 88 is output in accordance with the analyzed signal. The output information of the semiconductor device 80 is encoded through the output unit circuit 94. Further, the encoded information of the semiconductor device 80 passes through the data modulation circuit 86 and is transmitted on the radio signal by the antenna 89. Note that in a plurality of circuits included in the semiconductor device 80, a low power supply potential (hereinafter referred to as VSS) is common and VSS can be GND.

  As described above, by transmitting a signal from the reader / writer to the semiconductor device 80 and receiving the signal transmitted from the semiconductor device 80 by the reader / writer, the data of the semiconductor device can be read.

  Further, the semiconductor device 80 may be of a type in which power supply voltage is supplied to each circuit by electromagnetic waves without mounting a power supply (battery), or each circuit is mounted by electromagnetic waves or power supply (battery). It is good also as a type which supplies a power supply voltage to.

  Next, an example of a usage pattern of a semiconductor device capable of inputting and outputting data without contact will be described. A reader / writer 3200 is provided on a side surface of the portable terminal including the display portion 3210, and a semiconductor device 3230 is provided on a side surface of the article 3220 (FIG. 17B). When the reader / writer 3200 is held over the semiconductor device 3230 included in the product 3220, information about the product such as the description of the product, such as the raw material and origin of the product, the inspection result for each production process and the history of the distribution process, is displayed on the display unit 3210. Is done. In addition, when the product 3260 is conveyed by the belt conveyor, the product 3260 can be inspected using the reader / writer 3240 and the semiconductor device 3250 provided in the product 3260 (FIG. 17C). In this manner, by using a semiconductor device in the system, information can be easily acquired, and high functionality and high added value are realized.

  In addition to the above, the semiconductor device of the present invention has a wide range of uses, and is applicable to any product that can be used for production and management by clarifying information such as the history of an object without contact. be able to. For example, banknotes, coins, securities, certificate documents, bearer bonds, packaging containers, books, recording media, personal belongings, vehicles, foods, clothing, health supplies, daily necessities, chemicals, etc. It can be provided and used in an electronic device or the like. These examples will be described with reference to FIG.

  Banknotes and coins are money that circulates in the market, and include those that are used in the same way as money in a specific area (cash vouchers), commemorative coins, and the like. Securities refer to checks, securities, promissory notes, etc. (FIG. 18A). The certificate refers to a driver's license, resident's card, etc. (FIG. 18B). Bearer bonds refer to stamps, gift tickets, various gift certificates, and the like (FIG. 18C). Packaging containers refer to wrapping paper for lunch boxes, plastic bottles, and the like (FIG. 18D). Books refer to books, books, and the like (FIG. 18E). The recording media refer to DVD software, video tapes, and the like (FIG. 18F). The vehicles refer to vehicles such as bicycles, ships, and the like (FIG. 18G). Personal belongings refer to bags, glasses, and the like (FIG. 18H). Foods refer to food products, beverages, and the like. Clothing refers to clothing, footwear, and the like. Health supplies refer to medical equipment, health equipment, and the like. Livingware refers to furniture, lighting equipment, and the like. Chemicals refer to pharmaceuticals, agricultural chemicals, and the like. Electronic devices refer to liquid crystal display devices, EL display devices, television devices (television receivers, thin television receivers), cellular phones, and the like.

  Forgery can be prevented by providing the semiconductor device 80 on bills, coins, securities, certificates, bearer bonds, and the like. In addition, by providing semiconductor devices 80 in personal items such as packaging containers, books, recording media, personal items, foods, daily necessities, electronic devices, etc., the efficiency of inspection systems and rental store systems will be improved. Can do. By providing the semiconductor device 80 in vehicles, health supplies, medicines, etc., it is possible to prevent counterfeiting and theft, and in the case of medicines, it is possible to prevent mistakes in taking medicines. As a method of providing the semiconductor device 80, the semiconductor device 80 is provided by being attached to the surface of the article or embedded in the article. For example, a book may be embedded in paper, and a package made of an organic resin may be embedded in the organic resin.

  In this way, by providing semiconductor devices in packaging containers, recording media, personal items, foods, clothing, daily necessities, electronic devices, etc., it is possible to improve the efficiency of inspection systems and rental store systems. it can. Further, forgery or theft can be prevented by providing a semiconductor device in the vehicles. Moreover, by embedding it in creatures such as animals, it is possible to easily identify individual creatures. For example, by embedding a semiconductor device equipped with a sensor in a living creature such as livestock, it is possible to easily manage health conditions such as body temperature as well as the year of birth, gender or type.

  Note that this embodiment can be freely combined with any of the other embodiments in this specification.

FIG. 11 illustrates an example of a semiconductor device of the invention. 4A and 4B illustrate an example of a method for manufacturing a semiconductor device of the present invention. 4A and 4B illustrate an example of a method for manufacturing a semiconductor device of the present invention. 4A and 4B illustrate an example of a method for manufacturing a semiconductor device of the present invention. 4A and 4B illustrate an example of a method for manufacturing a semiconductor device of the present invention. 4A and 4B illustrate an example of a method for manufacturing a semiconductor device of the present invention. FIG. 11 illustrates an example of a semiconductor device of the invention. FIG. 11 illustrates an example of a semiconductor device of the invention. FIG. 14 illustrates an example of a memory portion included in a semiconductor device of the invention. 4A and 4B illustrate an example of a method for manufacturing a semiconductor device of the present invention. 4A and 4B illustrate an example of a method for manufacturing a semiconductor device of the present invention. 4A and 4B illustrate an example of a method for manufacturing a semiconductor device of the present invention. FIG. 13 illustrates an example of a usage pattern of a semiconductor device of the invention. FIG. 13 illustrates an example of a usage pattern of a semiconductor device of the invention. FIG. 11 illustrates an example of a semiconductor device of the invention. FIG. 13 illustrates an example of a usage pattern of a semiconductor device of the invention. FIG. 11 illustrates an example of a semiconductor device of the invention. FIG. 11 illustrates an example of a semiconductor device of the invention. 6A and 6B illustrate an example of a conventional semiconductor device. 4A and 4B illustrate an example of a method for manufacturing a semiconductor device of the present invention. FIG. 11 illustrates an example of a semiconductor device of the invention. FIG. 14 illustrates an example of a memory portion included in a semiconductor device of the invention. FIG. 14 illustrates an example of a memory portion included in a semiconductor device of the invention.

Explanation of symbols

80 Semiconductor device 81 High frequency circuit 82 Power supply circuit 83 Reset circuit 84 Clock generation circuit 85 Data demodulation circuit 86 Data modulation circuit 87 Control circuit 88 Storage circuit 89 Antenna 91 Code extraction circuit 92 Code determination circuit 93 CRC determination circuit 94 Output unit circuit 106 Insulation Film 130 Insulating film 131 Thin film integrated circuit 132 Conductive film 133 Substrate 134 Conductive particle 135 Resin 136 Conductive film 151 Transistor 152 Transistor 201 Substrate 202 Insulating film 203 Semiconductor film 204 Gate insulating film 205 Conductive film 206 Conductive film 207 Insulating film 208 Insulating film 209 conductive film 211 resist 212 impurity region 213 semiconductor film 214 gate insulating film 215 conductive film 216 conductive film 217 insulating film 218 sidewall 220 stacked body 221 resist 223 semiconductor film 22 Gate insulating film 225 Conductive film 231 Resist 234 Gate insulating film 235 Conductive film 244 Gate insulating film 245 Conductive film 301 Substrate 302 Insulating film 303 Semiconductor film 304 Insulating film 305 Charge storage layer 306 Charge storage layer 307 Stack 308 Semiconductor film 309 Insulating film 310 insulating film 311 insulating film 312 conductive film 313 resist 314 insulating film 315 charge storage layer 316 insulating film 317 conductive film 318 insulating film 319 conductive film 322 insulating film 323 conductive film 325 resist 901 substrate 902 insulating film 903 semiconductor film 904 gate insulating film 905 conductive film 907 conductive film 200a thin film transistor 200b thin film transistor 203a channel formation region 203b impurity region 203c impurity region 203d impurity region 213a channel formation region 213b impurity region 213d Physical region 230a Laminated body 230b Laminated body 307a Semiconductor film 307b Insulating film 307c Charge storage layer 310a Insulating film 310b Insulating film 3200 Reader / writer 320a Channel forming region 320b Impurity region 3210 Display part 321a Channel forming region 321b Impurity region 3220 Product 3230 Semiconductor device 3240 reader / writer 3250 semiconductor device 3260 product 903a channel formation region 903b impurity region 953b impurity region

Claims (13)

A semiconductor film provided in an island shape on the substrate;
A gate insulating film provided in contact with the surface of the semiconductor film;
An insulating film provided in contact with a side surface of the semiconductor film;
A first conductive film provided in contact with the surface of the gate insulating film;
A second conductive film provided in contact with the surface of the first conductive film and the surface of the insulating film;
A position of a part of an end portion of the semiconductor film is coincident with a position of a part of an end portion of the first conductive film. A semiconductor film provided in an island shape on the substrate;
A gate insulating film provided in contact with the surface of the semiconductor film;
An insulating film provided in contact with a part of a side surface of the semiconductor film;
A first conductive film provided in contact with the surface of the gate insulating film;
A second conductive film provided in contact with the surface of the first conductive film and the surface of the insulating film;
A sidewall provided in contact with a side surface of the first conductive film and a side surface of the second conductive film;
A position of a part of an end portion of the semiconductor film is coincident with a position of a part of an end portion of the first conductive film. In claim 2,
The semiconductor device is characterized in that an end portion of the insulating film and an end portion of the side wall coincide with each other. A semiconductor film having a channel formation region, a source region, a drain region, and an impurity region having a conductivity type different from that of the source region and the drain region;
A gate insulating film provided in contact with the surface of the semiconductor film;
An insulating film provided in contact with a side surface of the semiconductor film;
A first conductive film provided in contact with the surface of the gate insulating film;
A second conductive film provided in contact with the surface of the first conductive film and the surface of the insulating film;
The channel formation region is provided between the source region and the drain region,
The impurity region is provided at an end of the semiconductor film and adjacent to the channel formation region, the source region, and the drain region,
A position of a part of an end portion of the semiconductor film is coincident with a position of a part of an end portion of the first conductive film. In any one of Claims 1 thru | or 4,
A semiconductor device, wherein a surface of the insulating film and a surface of the first conductive film coincide with each other. In any one of Claims 1 thru | or 5,
The semiconductor device, wherein the insulating film is thicker than the semiconductor film. A semiconductor film provided in an island shape on the substrate;
A first insulating film provided in contact with a side surface of the semiconductor film;
A second insulating film provided in contact with the surface of the semiconductor film;
A charge storage layer provided on the second insulating film;
A third insulating film provided in contact with the surface of the charge storage layer and the surface of the first insulating film;
A conductive film formed on the third insulating film;
A position of a part of the end portion of the semiconductor film and a position of a part of the end portion of the charge storage layer coincide with each other. A semiconductor film provided in an island shape on the substrate;
A first insulating film provided in contact with a part of a side surface of the semiconductor film;
A second insulating film provided in contact with the surface of the semiconductor film;
A charge storage layer provided on the second insulating film;
A third insulating film provided in contact with the surface of the charge storage layer and the surface of the first insulating film;
A conductive film formed on the third insulating film;
The charge storage layer, the second insulating film, and a sidewall provided in contact with a side surface of the conductive film;
A position of a part of the end portion of the semiconductor film and a position of a part of the end portion of the charge storage layer coincide with each other. In claim 8,
An end portion of the first insulating film, an end portion of the second insulating film, and an end portion of the conductive film are aligned with each other. In any one of Claims 7 to 9,
A semiconductor device, wherein a surface of the semiconductor film and a surface of the first insulating film coincide with each other. Forming a stacked body in which a semiconductor film, a gate insulating film, and a first conductive film are sequentially stacked on a substrate;
By selectively removing the laminate, a plurality of laminates provided in an island shape,
An insulating film is formed so as to cover the laminated body provided in the island shape,
Removing a portion of the insulating film so that the height of the surface of the first conductive film is approximately the same as the height of the first conductive film to expose the surface of the first conductive film;
Forming a second conductive film on the first conductive film and the remaining insulating film;
A method for manufacturing a semiconductor device, comprising: forming a resist over the second conductive film; and selectively removing the first conductive film and the second conductive film using the resist as a mask. Forming a stacked body in which a semiconductor film, a gate insulating film, and a first conductive film are sequentially stacked on a substrate;
By selectively removing the laminate, a plurality of laminates provided in an island shape,
An insulating film is formed so as to cover the laminated body provided in the island shape,
Removing a portion of the insulating film so that the height of the surface of the first conductive film is approximately the same as the height of the first conductive film to expose the surface of the first conductive film;
Forming a second conductive film on the first conductive film and the remaining insulating film;
Forming a resist on the second conductive film, and selectively removing the first conductive film and the second conductive film using the resist as a mask;
A first impurity region is formed in the semiconductor film by selectively introducing a first impurity element into the semiconductor film using the first conductive film and the second conductive film as a mask;
Forming sidewalls so as to be in contact with the side surfaces of the first conductive film and the second conductive film;
A second impurity region is formed in the semiconductor film by selectively introducing a second impurity element into the semiconductor film using the first conductive film, the second conductive film, and the sidewalls as a mask. A method for manufacturing a semiconductor device. Forming a stacked body in which a semiconductor film, a first insulating film, and a charge storage layer are sequentially stacked on a substrate;
By selectively removing the laminate, a plurality of laminates provided in an island shape,
Forming a second insulating film so as to cover the laminate provided in the island shape;
Removing a portion of the second insulating film so that the height of the surface of the semiconductor film substantially matches the height of the semiconductor film to expose the surface of the charge storage layer;
Forming a third insulating film on the charge storage layer and the remaining second insulating film;
Forming a conductive film on the third insulating film;
Forming a resist over the conductive film, and selectively removing the first insulating film, the charge storage layer, the third insulating film, and the conductive film using the resist as a mask; Device fabrication method.

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