Abstract: An increase in voltage of a light-emitting device manufactured through a step of forming an aluminum oxide film in contact with an organic compound layer is inhibited. An organic compound film is formed over a first electrode. An organic mask film containing an organic compound which has low solubility to water or a chemical solution including water as a solvent is formed over the organic compound film. An inorganic mask layer is formed over the organic mask film. Shapes of the organic mask film and the organic compound film are processed with the use of the inorganic mask layer, whereby an organic mask layer and an organic compound layer are formed. At least parts of the inorganic mask layer and the organic mask layer are removed with the use of water or a liquid including water as a solvent.

Abstract: An organic semiconductor device that can achieve high resolution and favorable reliability is provided. The organic semiconductor device is one of a plurality of light-emitting devices formed over an insulating layer, which includes a first electrode, a second electrode, and an organic compound layer. The organic compound layer is positioned between the first electrode and the second electrode. The organic compound layer includes a layer containing a first compound. When differential scanning calorimetry is performed on the first compound in such a manner that a cooling step is performed from the state in which the first compound is melted in a first heating step and a second heating step is successively performed, an exothermic peak is not observed in the cooling step and an exothermic peak and a melting point peak are not observed in the second heating step.

Abstract: A novel organic compound is provided. Alternatively, an organic compound that emits light with favorable chromaticity is provided. Alternatively, an organic compound that emits blue light with favorable chromaticity is provided. Alternatively, a light-emitting element with favorable emission efficiency is provided. Alternatively, an organic compound with an excellent carrier-transport property is provided. The organic compound includes any of a substituted or unsubstituted dibenzofurobisbenzofuran skeleton, a substituted or unsubstituted dibenzothienobisbenzothiophene skeleton, a substituted or unsubstituted benzobisbenzothienobenzofuran skeleton, and a substituted or unsubstituted dibenzothienobisbenzofuran skeleton and one or two amino groups.

Abstract: An object is to provide a highly reliable display unit having a function of sensing light. The display unit includes a light-receiving device and a light-emitting device. The light-receiving device includes an active layer between a pair of electrodes. The light-emitting device includes a hole-injection layer, a light-emitting layer, and an electron-transport layer between a pair of electrodes. The light-receiving device and the light-emitting device share one of the electrodes, and may further share another common layer between the pair of electrodes. The hole-injection layer is in contact with an anode and contains a first compound and a second compound. The electron-transport property of the electron-transport layer is low; hence, the light-emitting layer is less likely to have excess electrons. Here, the first compound is the material having a property of accepting electrons from the second compound.

Abstract: A light-emitting element which includes a plurality of light-emitting layers between a pair of electrodes and has low driving voltage and high emission efficiency is provided. A light-emitting element including first to third light-emitting layers between a cathode and an anode is provided. The first light-emitting layer includes a first phosphorescent material and a first electron-transport material; the second light-emitting layer includes a second phosphorescent material and a second electron-transport material; the third light-emitting layer includes a fluorescent material and a third electron-transport material; the first to third light-emitting elements are provided in contact with an electron-transport layer positioned on a cathode side; and a triplet excitation energy level of a material included in the electron-transport layer is lower than triplet excitation energy levels of the first electron-transport material and the second electron-transport material.

Abstract: To inhibit an increase in voltage of an organic semiconductor device manufactured by a method including a step of forming an aluminum oxide film over and in contact with an organic semiconductor layer. An organic semiconductor device including a first electrode, a second electrode, an organic semiconductor layer, and a buffer layer is provided. The organic semiconductor layer is positioned between the first electrode and the second electrode. The buffer layer is positioned between the organic semiconductor layer and the second electrode. A side surface of the organic semiconductor layer and a side surface of the buffer layer are substantially aligned.

Abstract: A novel light-emitting element is provided. A light-emitting element with a long lifetime is provided. A light-emitting element with high emission efficiency is provided. In the light-emitting element, an EL layer includes a hole-injection layer, a first hole-transport layer, a second hole-transport layer, a third hole-transport layer, a light-emitting layer, a first electron-transport layer, and a second electron-transport layer in this order; the hole-injection layer includes an organic acceptor; the LUMO level of the host material is higher than that of the first electron-transport layer; the LUMO level of the second electron-transport layer is higher than that of the first electron-transport layer; the host material is a substance including a condensed aromatic ring skeleton; and the first and second electron-transport layers each include a substance having a heteroaromatic ring skeleton.

Abstract: An object is to provide a highly reliable display unit having a function of sensing light. The display unit includes a light-receiving device and a light-emitting device. The light-receiving device includes an active layer between a pair of electrodes. The light-emitting device includes a hole-injection layer, a light-emitting layer, and an electron-transport layer between a pair of electrodes. The light-receiving device and the light-emitting device share one of the electrodes, and may further share another common layer between the pair of electrodes. The hole-injection layer is in contact with an anode and contains a first compound and a second compound. The electron-transport property of the electron-transport layer is low; hence, the light-emitting layer is less likely to have excess electrons. Here, the first compound is the material having a property of accepting electrons from the second compound.

Abstract: An organic compound has a benzonaphthofuran skeleton and is represented by General Formula (G1). In General Formula (G1), A represents a pyrene skeleton. In the case where the pyrene skeleton has a substituent, the substituent is a diarylamino group including two substituted or unsubstituted aryl groups each having 6 to 13 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, an alkyl group having 1 to 7 carbon atoms, a substituted or unsubstituted monocyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a substituted or unsubstituted polycyclic saturated hydrocarbon group having 7 to 10 carbon atoms. The two aryl groups of the diarylamino group may be the same or different.

Abstract: A light-emitting device including at least a light-emitting layer between an anode and a cathode; the light-emitting layer contains at least a light-emitting substance; the light-emitting substance is a substance emitting fluorescent light; a first organic compound represented by General Formula (G1) is included between the anode and the cathode; in General Formula (G1), Ar1 represents a substituted or unsubstituted fluorenyl group, Ar2 represents a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, and A1 represents a substituted or unsubstituted dibenzofuranyl group or a substituted or unsubstituted dibenzothiophenyl group; when at least one of Ar1, Ar2, and A1 has one or more substituents, the substituents each independently represent an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 13 carbon atoms. The aryl group exclude a heteroaryl group. The substituents may be bonded to each other to form a ring.

Abstract: A light-emitting device with a long lifetime is provided. A light-emitting device with a low driving voltage is provided. In the light-emitting device, an electron-transport layer includes an organometallic complex of an alkali metal and an organic compound having an electron-transport property; the organometallic complex and the organic compound form an exciplex in combination; a value (eV) obtained by converting into energy a peak wavelength of an emission spectrum of the exciplex formed with the organometallic complex and the organic compound having a mass ratio of 1:1 is smaller than a difference (eV) between a HOMO level of the organometallic complex and a LUMO level of the organic compound by greater than or equal to 0.1 eV.

Abstract: An object is to provide a novel organic compound. Another object is to provide a novel light-emitting device. Another object is to provide a light-emitting device with favorable emission efficiency. Another object is to provide a light-emitting device with a favorable lifetime. Another object is to provide a light-emitting device with a low driving voltage. A dibenzo[c,g]carbazole derivative represented by the following general formula (G1) and a light-emitting device using it are provided. Note that at least one of R11 to R22 represents a substituent that has 14 to 60 carbon atoms in total and contains a condensed tricyclic to hexacyclic aromatic hydrocarbon skeleton, and the others independently represent any of hydrogen, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and a substituted or unsubstituted aryl group having 6 to 25 carbon atoms.

Abstract: A light-emitting device with high emission efficiency is provided. The light-emitting device includes at least a light-emitting layer between an anode and a cathode. The light-emitting layer contains a light-emitting substance, a first organic compound, and a second organic compound. The light-emitting substance is a substance that emits fluorescent light. The first organic compound has any one of an anthracene skeleton, a tetracene skeleton, a phenanthrene skeleton, a pyrene skeleton, a chrysene skeleton, a carbazole skeleton, a benzocarbazole skeleton, a dibenzocarbazole skeleton, a dibenzofuran skeleton, a benzonaphthofuran skeleton, a bisnaphthofuran skeleton, a dibenzothiophene skeleton, a benzonaphthothiophene skeleton, a bisnaphthothiophene skeleton, and a fluoranthene skeleton.

Abstract: A novel light-emitting device is provided. A light-emitting device with high emission efficiency is provided. A light-emitting device with a long lifetime is provided. A light-emitting device with low driving voltage is provided. The light-emitting device includes an anode, a cathode, and an EL layer between the anode and the cathode. The EL layer includes a hole-injection layer, a light-emitting layer, and an electron-transport layer. The hole-injection layer is positioned between the anode and the light-emitting layer. The electron-transport layer is positioned between the light-emitting layer and the cathode. The hole-injection layer contains a first substance and a second substance. The first substance is an organic compound which has a hole-transport property and a HOMO level higher than or equal to ?5.7 eV and lower than or equal to ?5.4 eV. The second substance exhibits an electron-accepting property with respect to the first substance.

Abstract: A light-emitting device with high resistance to heat in a fabrication process is provided. The light-emitting device includes an EL layer between an anode and a cathode, and the EL layer includes at least a light-emitting layer. The light-emitting device includes, between the light-emitting layer and the cathode, a first layer in contact with the light-emitting layer. The light-emitting layer includes a light-emitting substance, a first organic compound, and a second organic compound. The first layer includes a third organic compound different from the first organic compound and the second organic compound. The light-emitting substance emits green to yellow light. The third organic compound includes a bicarbazole skeleton and a heteroaromatic ring skeleton including one selected from a pyridine ring, a diazine ring, and a triazine ring.

Abstract: A novel organic compound that is highly convenient, useful, or reliable is provided. The organic compound is represented by General Formula (G1). Note that at least one of R1 to R26 represents deuterium. At least one of R1 to R7 represents any one of an alkyl group, a cycloalkyl group, a trialkylsilyl group, and an aryl group. The others of R1 to R7 each independently represent any one of hydrogen, an alkyl group, a cycloalkyl group, a trialkylsilyl group, and an aryl group. R8 to R26 each independently represent any one of hydrogen, an alkyl group, a cycloalkyl group, a trialkylsilyl group, and an aryl group. The alkyl group has 3 to 10 carbon atoms, the cycloalkyl group has 3 to 10 carbon atoms, the trialkylsilyl group has 3 to 12 carbon atoms, and the aryl group has 6 to 25 carbon atoms.

Abstract: A light-emitting device with high heat resistance is provided. The light-emitting layer device includes an anode, a cathode; and an EL layer between the anode and the cathode. The EL layer includes a light-emitting layer and a first layer. The first layer is between the light-emitting layer and the cathode. The light-emitting layer is in contact with the first layer. The light-emitting layer includes a first organic compound and a light-emitting substance. The first layer includes a second organic compound. The light-emitting substance is a substance that emits blue light. The first organic compound is an organic compound including a fused aromatic hydrocarbon ring. The second organic compound is an organic compound including a heteroaromatic ring skeleton including one selected from a pyridine ring, a diazine ring, and a triazine ring; and a bicarbazole skeleton.

Abstract: A light-emitting device having favorable heat resistance is provided. The light-emitting device includes an anode, a cathode, and an EL layer positioned between the first anode and the cathode. The EL layer includes a light-emitting layer and a first layer. The first layer is positioned between the light-emitting layer and the cathode. The light-emitting layer and the first layer are in contact with each other. The light-emitting layer contains a first organic compound, a second organic compound, and a light-emitting substance. The first layer contains a third organic compound. The first organic compound and the third organic compound each have an electron-transport property. The second organic compound has a hole-transport property. The light-emitting substance emits red light. The first organic compound is represented by General Formula (G100). The third organic compound is represented by General Formula (G300).

Abstract: A novel light-emitting element is provided. A light-emitting element with a long lifetime is provided. A light-emitting element with high emission efficiency is provided. In the light-emitting element, an EL layer includes a hole-injection layer, a first hole-transport layer, a second hole-transport layer, a third hole-transport layer, a light-emitting layer, a first electron-transport layer, and a second electron-transport layer in this order; the hole-injection layer includes an organic acceptor; the LUMO level of the host material is higher than that of the first electron-transport layer; the LUMO level of the second electron-transport layer is higher than that of the first electron-transport layer; the host material is a substance including a condensed aromatic ring skeleton; and the first and second electron-transport layers each include a substance having a heteroaromatic ring skeleton.

Abstract: A light-emitting device with high resistance to heat in a fabrication process is provided. The light-emitting device includes an EL layer between an anode and a cathode. The EL layer includes at least a light-emitting layer and an electron-transport layer that includes a first electron-transport layer in contact with the light-emitting layer and a second electron-transport layer in contact with the first electron-transport layer. The first electron-transport layer includes a first heteroaromatic compound including at least one heteroaromatic ring. The second electron-transport layer includes a second heteroaromatic compound that includes at least one heteroaromatic ring and is different from the first heteroaromatic compound. The first heteroaromatic compound has a difference of 20° C. or less between the crystallization temperature (Tpc) of a powder state and the crystallization temperature (Ttc) of a thin film state. The second heteroaromatic compound has a difference of 100° C. or less between Tpc and Ttc.