Nitride semiconductor multilayer structure, method for producing same, and nitride semiconductor light-emitting element

Method for producing a nitride semiconductor multilayer structure, by low-pressure MOVPE under a condition where a single crystal substrate is disposed in a reactor, comprising:

• step (a) of forming, on one surface of the single crystal substrate, a plurality of island-like nuclei formed of a nitride semiconductor that contains Al as a constituent element, by supplying an Al raw material gas and a N raw material gas into the reactor under a predefined substrate temperature and a predefined growth pressure and under a condition where a ratio of the amount of substance of the N raw material gas with respect to the amount of substance of the Al raw material gas is set to a first amount of substance ratio;
• step (b) of forming a first nitride semiconductor layer so as to fill gaps between adjacent nuclei and to cover all the nuclei, by supplying an Al raw material gas and a N raw material gas into the reactor under a predefined substrate temperature and a predefined growth pressure and under a condition where a ratio of the amount of substance of the N raw material gas with respect to the amount of substance of the Al raw material gas is set to a second amount of substance ratio;
• and
• step (c) of forming a second nitride semiconductor layer on the first nitride semiconductor layer, by supplying an Al raw material gas and a N raw material gas into the reactor under a predefined substrate temperature and a predefined growth pressure and under a condition where a ratio of the amount of substance of the N raw material gas with respect to the amount of substance of the Al raw material gas is set to a third amount of substance ratio,
• wherein
• the first nitride semiconductor layer and the second nitride semiconductor layer contain Al as a constituent element, respectively, and
• the substrate temperatures in the steps (a) to (c) are set to same, and the growth pressures in the steps (a) to (c) for forming the nuclei, the first nitride semiconductor layer and the second nitride semiconductor layer are set to same.