Abstract:
PURPOSE: A light emitting device is provided to improve the spontaneous emission efficiency of a quantum well by efficiently reducing a spatial separation phenomenon of electrons and holes in an active layer. CONSTITUTION: An active layer(114) includes a quantum well(114w) and a quantum wall(114b). The quantum well and the quantum wall are formed between a first conductive semiconductor layer and a second conductive semiconductor layer. An energy band gap becomes parabolic from the edge to the center of the quantum well. The energy band gap gradually increases from the edge to the center of the quantum well.
Abstract:
PURPOSE: A light emitting device is provided to improve the performance of a light emitting device by using an energy band gap and calculating a polarization charge. CONSTITUTION: An active layer(114) includes a quantum well and a quantum wall. The active layer is formed on a first conductive type semiconductor layer(112). A second conductive semiconductor layer(116) is formed on the active layer. The plurality of quantum walls and quantum well are laminated on the active layer. The light emitting structure includes the active layer and the nitride semiconductor layer.
Abstract:
The present invention relates to a high-efficiency blue InGaN/GaN quantum well LED with a saw-like layer. A light emitting property of the saw-like InGaN/GaN quantum well (QW) is inspected by using a multi-band effective mass theory. A spontaneous emission peak of a saw-like QW structure is improved compared to a conventional QW structure by adding a saw-like layer into a matrix element. In the saw-like QW structure, an inner field effect is reduced by a piezoelectric effect and a spontaneous polarization in the well, and an embedded electric field effect is decreased by a transition energy which is represented by a weak function of a carrier density. The inner electric field effect is decreased by adopting a method using a substrate with a non-(0001) orientation, a method using an InGaN/GaN well with In-rich films, and a method using an AlInGaN barrier having four groups. The high-efficiency non-square quantum well structure is realized by using a method similar to a manufacturing method of a 3-layered nonsquare quantum well (QW) structure.
Abstract:
PURPOSE: A method for theoretically analyzing optical properties of an InGaN/CdZnO quantum well structure which is matched up to be biased is provided to remarkably improve optical matrix elements by removing the polarity of inner electric field by the invalidation of spontaneous polarization and piezoelectric polarization between a well and an obstacle. CONSTITUTION: A method for theoretically analyzing optical properties of an InGaN/CdZnO quantum well structure which is matched up to be biased includes the following steps of: acquiring a wave function by using Hamiltonian (Step1); acquiring a valence strip by using one method of a logical self-consistent and a Poisson equation by using an acquired wave function (Step2); acquiring many-body optical spectra by using the acquired valence strip (Step3); and comparing the result of the many-body optical spectrum with properties of a light emitting element. [Reference numerals] (AA) Start; (BB,EE) Step of acquiring a wave function; (CC) Step of acquiring a valence strip; (DD) Step of acquiring many-body optical spectra; (FF) End; (S1) Acquire a wave function by using Hamiltonian; (S2) Acquire a valence strip; (S3) Acquire many-body optical spectra; (S4) Compare the result of the many-body optical spectrum with properties of an existing light emitting element