100 results about "Electron leakage" patented technology

A memory uses multiple threshold levels in a memory cell that are not a power of two, and further uses a cell mapping technique wherein the read mapping is only a partial function The domain of read states for a single three-level memory cell, for example, has three states, but only two of them can be uniquely mapped to a bit. The domain of read states for two three-level memory cell, for example, has nine states, but only eight of them can be uniquely mapped to three bits. Although the read mapping is only partial, the voltage margin for the three-level memory cells is larger that the voltage margin available in the commonly used four-level memory cells. This increased voltage margin facilitates memory cell threshold voltage sensing, thereby increasing the reliability of the memory. Memory reliability may be further improved by increasing the voltage margin between the memory cell 0 state and the 1 state relative to the voltage margin between the 1 state and the 2 state, which more effectively accommodates charge loss from the 0 state through electron leakage. Asymmetrical read and program mapping may also be used to improve read reliability in the presence of ground noise or VCC noise.

The present disclosure relates to photosensitive optoelectronic devices comprising at least one of an electron blocking or hole blocking layer. Further disclosed are methods of increasing power conversion efficiency in photosensitive optoelectronic devices using at least one of an electron blocking or hole blocking layer. The electron blocking and hole blocking layers presently disclosed may reduce electron leakage current by reducing the dark current components of photovoltaic cells. This work demonstrates the importance of reducing dark current to improve power conversion efficiency of photovoltaic cells.

The present invention, in one aspect, relates to a solar cell. In one embodiment, the solar cell includes an anode; an active organic layer comprising an electron-donating organic material and an electron-accepting organic material; a semiconducting layer formed between the anode and the active organic layer; and an electron-blocking layer (EBL) formed between the semiconducting layer and the active organic layer, where the EBL is transparent and adapted for blocking electron leakage from the active organic layer to the anode while transporting holes from the active organic layer to the anode.

The invention provides an electron blocking layer structure of a photoelectric device. The electron blocking layer structure is characterized in that structure matching between a quantum well and a P layer is achieved through adjusting a lattice structure and a band gap as much as possible; meanwhile, the formation of a polarized electric field is reduced, the formation of a negative charge area in an electron blocking layer is weakened as much as possible, and further the efficiency is improved; the electron leakage caused by energy band bending of the electron blocking layer and the increment of hole potential energy of the P layer are weakened. The electron blocking layer structure of the photoelectric device adopts AlInGaN or AlInGaN/InGaN super-lattice structure growth, wherein the In component is less than or equal to 10 percent; the Al component is less than or equal to 40 percent; the gradual distribution of the In component and the Al component exists in the electron blocking layer, and gradual change principles of the In component and the Al component are mutually independent; as for the electron blocking layer with an AlInGaN/InGaN super-lattice structure, the gradual change of the In component occurs in a super-lattice AlInGaN or a super-lattice AlInGaN/InGaN or in both the super-lattice AlInGaN and the super-lattice AlInGaN/InGaN.

The invention provides a light-emitting diode with a novel P-type electron barrier layer structure and a growth method. The LED epitaxy structure of the light-emitting diode comprises a substrate, a low-temperature GaN buffer layer, a GaN non doping layer, an N-type GaN layer, a multiple quantum well layer, a low-temperature GaN layer, a P-type InAlGaN electron barrier layer, a high-temperature P-type GaN layer and a P-type contact layer which are sequentially arranged from bottom to top. According to a P-type InyAlxGal-x-yN electron barrier layer of the composite structure, In components are added, and the InyAlxGal-x-yN lattice constant is adjusted, so that lattice matching between the P-type GaN layer and the multiple quantum well layer can be achieved, dislocation density is reduced, lattice quality is improved, and expected energy band gap value and energy band drift rate are obtained. Consequently, electron leakage is effectively reduced, and the injection rate of holes is improved. Moreover, a gradually-changing structure of the P-type InAlGaN drift rate is designed, and the restriction to hole vertical migration is avoided, so that the injection efficiency of holes is improved, and the light-emitting efficiency of a GaN-based light-emitting diode is further improved.

The invention discloses a light emitting diode with an electronic barrier layer structure. The forbidden band width and lattice constant of a quaternary nitride InxAlyGa1-x-yN can be independently adjusted, the In and Al ingredients in p-InxAlyGa1-x-yN are adjusted to match with the lattice between GaN in a binary nitride or a ternary nitride or a InGaN/GaN multi-quantum well and the GaN in a p type GaN epitaxial layer so as to obtain high energy band gap value and energy band offset ratio, effectively reduce the electron leakage rate and improve the injection efficiency of holes, thereby greatly improving the light emission efficiency and ESD yield of LED devices.

The invention provides an InGaN/GaN superlattice buffer layer structure, a preparation method of the InGaN/GaN superlattice buffer layer structure, and an LED chip comprising the InGaN/GaN superlattice buffer layer structure. The InGaN/GaN superlattice buffer layer structure comprises a shallow quantum well layer, an MQW layer and a superlattice buffer layer disposed between the shallow quantum well layer and the MQW layer. The superlattice buffer layer comprises a plurality of buffer layer units stacked in order. Each buffer layer unit comprises an InGaN layer and a plurality of doped layers. Each doped layer comprises a uGaN layer and an nGaN layer which are stacked in order. Each doped layer is arranged on the corresponding InGaN layer. The InGaN/GaN superlattice buffer layer structure has the advantages that the quality of active region crystal of the LED chip can be improved, active region lattice mismatch and thermal stress mismatch are reduced, electron leakage is reduced effectively, carriers and holes can be recombined more efficiently, and luminous efficiency of devices is improved.

n-ZnO film in 50-150nm thickness deposited on glass substrate is as channel of thin film transistor (TFT). ATO film is as gate insulation layer, and ITO film is adopted in source, gate and drain poles. light transmittance in the transparent TFT reaches to more than 80% in visible light region. Comparing with general Si TFT, the invention prevents photo-electron leakage current generated between source and drain poles caused by incident light so that cutting off current will not rise. Features are: simple technique, suitable to active matrix LCD.

The application provides an ultraviolet LED epitaxial structure which includes a substrate, and an undoped buffer layer, an N-type AlGaN layer, a multiple-quantum-well structure, a superlattice structure, an electron blocking layer, a P-type AlGaN layer and a P-type GaN layer grown on the substrate in sequence. The superlattice structure includes at least one first AlGaN layer and at least one second AlGaN layer which are stacked alternately. As the superlattice structure is arranged between the multiple-quantum-well structure and the electron blocking layer, the strain between the last quantum barrier in the active region and the electron blocking layer can be alleviated, electron leakage can be inhibited, and the hole injection rate can be increased. Therefore, the light output power and internal quantum efficiency of ultraviolet LEDs are improved, and ultraviolet LEDs present better luminescent property.

The invention provides a growing method of an ultraviolet LED active area multiple quantum well. The growing method is characterized in that step1, a UGaN layer is grown on a sapphire substrate; step2, after the growing of the UGaN layer is ended, an N-GaN layer having stable doping concentration is grown; step 3, after the growing of the N-GaN layer is ended, a multiple quantum well structure MQW layer is grown; step 4, after the growing of the multiple quantum well structure MQW layer is ended, an active area multiple quantum well light-emitting layer is grown; step 5, after the growing of the active area multiple quantum well light-emitting layer is ended, a P-type gallium nitride layer taking N2 as a carrier gas is grown; step 6, after the growing of the P-type gallium nitride layer is ended, an LED epitaxial structure is acquired by adopting annealing treatment. By adopting the production technology provided by the invention, electron concentration distribution is optimized, and electron leakage is suppressed; stress generated during a multiple quantum well growing process is reduced, and quantum confinement stark effect (QCSE) is reduced; current injection efficiency is increased, and multiple quantum well light-emitting efficiency is improved.

Tunnel insulating films (3) are formed in element regions demarcated by element isolation insulating films (2). Thereafter, for each memory cell, a floating gate (4) is formed, and an ONO film (5) and a control gate (6) are further formed. Next, a plasma insulating film (7) is formed on surfaces of stacked gates. The plasma insulating film is immune to plane orientation of a base film. Therefore, the entire plasma insulating film (7) has a substantially uniform thickness, and consequently, even if the maximum thickness thereof is not as large as that of a thermal oxide film, hydrogen entrance is prevented when the interlayer insulating film is thereafter formed, and electron leakage is also prevented. The reduction in thickness of this insulating film makes it possible to reduce birds' beaks, and efficiency in erase/write of data can be enhanced.

The present invention provides a material for photoelectric conversion elements for use in imaging elements which comprises a compound represented by the following formula (1). The material for photoelectric conversion elements for use in imaging elements, which comprises a compound represented by the following formula (1), is used to produce a photoelectric conversion element which is excellent in terms of hole- or electron-leakage prevention, thermal resistance to processing temperatures, transparency to visible light, etc. (In formula (1), R₁ and R₂ each independently represent a substituted or unsubstituted aromatic group.)

The invention discloses a light-emitting diode with an electron blocking layer of a hole injection structure. The light-emitting diode comprises a substrate, a nitride buffer layer, an n-type nitridelayer, a multi-quantum well active region, a hole injection structure electron blocking layer, a p-type nitride layer and a transparent conductive layer which are sequentially arranged from bottom totop, and further comprises an n-type electrode arranged on the n-type nitride layer and a p-type electrode arranged on the transparent conductive layer. According to the light-emitting diode of the electron blocking layer of the hole injection structure, stress matching between the active region and the electron blocking layer is achieved, electron leakage is effectively restrained. Meanwhile, theprobability that Mg diffuses into the active region is reduced, and then the light-emitting efficiency of the LED is improved; the longitudinal migration capability of holes is improved, so that thehole injection efficiency is remarkably improved; the polarized electric field at the heterojunction interface forms two-dimensional hole gas on one side of the hole injection layer, so that the congestion effect of current is improved.

The invention relates to a manufacturing method for a nitride LED assembly. The method has the advantages of reducing electron leakage, relieving the efficiencydroop effect, increasing hole concentration and enhancing light-emitting efficiency. The method is implemented by the adoption of the steps that (1) a transition substrate is provided; (2) a P-type semiconductor layer and a first bonding layer sequentially grow on the transition substrate; (3) a permanent substrate is provided; (4) a N-type semiconductor layer, a light-emitting layer and a second bonding layer sequentially grow on the permanent substrate; (5) the transition substrate where the P-type semiconductor layer grows and the permanent substrate where the N-type semiconductor layer and the light-emitting layer grow are bonded through the first bonding layer and the second bonding layer.

The invention provides an epitaxial growth method for blocking electron leakage and defect extension. The method comprises letting NH3, TMGa and TMAl in between a growth multi-quantum well InxGa(1-x)N/GaN layer and a growth P-type GaN layer, and growing an electron barrier layer with a growth thickness of 8 to 25 nm, wherein the layer comprises two to six groups of double-layer structures, and compared to the Al component content of the UAlGaN layer of the last double-layer structure, the Al component content of the UAlGaN layer of each double-structure is increased by 15% to 50%. According to the invention, the UAlGaN/UGaN structure with layer-to-layer gradually increased Al components is utilized as an electron barrier layer, the single energy level height distribution of a conventional P-spacer energy band is changed, the blocking effects on cavity injection are weakened, and the MQW luminescence efficiency is improved.

The invention discloses a gallium nitride-based light emitting diode epitaxial wafer and a manufacturing method thereof, and belongs to the technical field of semiconductors. The gallium nitride-basedlight emitting diode epitaxial wafer comprises a substrate, an N-type semiconductor layer, an active layer, an electron barrier layer and a P-type semiconductor layer; the N-type semiconductor layer,the active layer, the electron barrier layer and the P-type semiconductor layer are sequentially stacked on the substrate; the electron barrier layer comprises a first sub-layer, a second sub-layer and a third sub-layer stacked in sequence; the first sub-layer is made from BxGa1-xN, and x is more than 0 and not more than 1; the second sub-layer is made from GaN; and the third sub-layer is made from ByGa1-yN, and y is more than 0 and not more than 1. According to the gallium nitride-based light emitting diode epitaxial wafer and the manufacturing method thereof, the GaN layer is inserted intothe BGaN layer or the BN layer, so that the electron leakage can be effectively reduced and the hole injection can be increased, and finally the light emitting efficiency of the LED can be improved.

The application discloses a method for growing an epitaxial structure of an LED. The method comprises: processing a substrate; growing a low-temperature buffer layer GaN; growing an undoped GaN layer;growing a Si-doped N type GaN layer; alternately growing InxGa(1-x)N/GaN multi-quantum well layers; growing a AlGaN electron blocking layer; growing a Mg-doped P type GaN layer; and then carrying cooling. According to the invention, on the basis of the multi-quantum well structures with the In content gradation of quantum well layers, barrier layer temperature gradation, and thickness gradation,problems of insufficient hole injection, serious electron leakage and low quantum well radiation recombination efficiency of the existing LED multi-quantum well layer can be solved, so that the luminous efficiency of the LED is improved.

The invention discloses an LED epitaxial growth method used for improving the internal quantum efficiency. The method sequentially comprises the steps of substrate processing, low-temperature buffer layer GaN growing, undoped GaN layer growing, Si-doped N-type GaN layer growing, AlGaN:Zn thin barrier layer growing, alternate InxGa(1-X)N/GaN light emitting layer growing, P-type AlGaN layer growing, Mg-doped P-type GaN layer growing, and cooling. The AlGaN:Zn thin barrier layer grows on one side, which is close to an N-type layer, of a light emitting layer to form an asymmetric well barrier structure to suppress the generation of electron leakage current. The injection efficiency of electrons and holes in a quantum well is improved. The internal quantum efficiency and the optical power of an LED are improved. The light emitting efficiency of the LED is enhanced.

The application discloses a light emitting diode and a preparation method thereof. According to the light emitting diode, the last quantum barrier layer of a plurality of quantum well layers and an electron blocking layer in a conventional structure are replaced with a super lattice structure comprising a plurality of first-type super lattice layers and a plurality of second-type super lattice layers; the super lattice structure reduces polarization electric field intensity of the last quantum barrier layer, improves an electron hole wave function overlapping degree of the light emitting diodeand is beneficial to radiation composite light emitting of the light emitting diode; and the super lattice structure not only reduces the preparation difficulty of the light emitting diode, but alsoenables growth of the high-quality super lattice structure and second-type contact layer to be possible. In addition, existence of the super lattice structure also enables a electronic barrier heightof a conduction band of the integral second-type structural layer to be further increased, greatly reduces electron leakage, meanwhile, reduces a barrier height of a valence band hole, promotes transmission of the hole, greatly promotes internal quantum efficiency of multiple quantum well layers, reduces sudden reduction of efficiency, and greatly promotes integral light emitting power of the light emitting diode.

The invention relates to a GaN-based light-emitting diode structure which comprises a substrate, an n-type GaN conductive layer, an n-type AlGaN limitation layer, an active region luminous layer, a p-type AlGaN limitation layer, a p electrode and an n electrode. A layer of p-type diamond film conductive layer is deposited on the upper surface or the lower surface of the p-type AlGaN limitation layer. The size of the cross sectional area of the p-type diamond film conductive layer is the same with the size of the p-type AlGaN limitation layer, and the thickness of the p-type diamond film conductive layer is 50-500 nm. The diamond film has a weak absorption effect on full-waveband light, so that light absorption is reduced, and light extraction efficiency of LED can be effectively improved; the forbidden band width of diamond is relatively large, so that the reflection effect on electrons is strong, electron leakage can be reduced, and brightness is improved; and the p-type diamond film is easy to dope, the hole concentration is relatively high, and ohmic contact is easy to prepare.

The invention discloses an epitaxial structure for improving light output power of an ultraviolet LED. The epitaxial structure comprises a substrate, a GaN buffer layer, a non-doped GaN layer, a doped N-type GaN layer, a AlGaN/GaN multi-quantum well structure, an insertion layer, an electron barrier layer EBL and a P-type GaN layer which are sequentially arranged from bottom to top, wherein the substrate employs a sapphire substrate, the thickness of the GaN buffer layer is 20-25 nanometers, the growth temperature of the GaN buffer layer is 530-550 DEG C, the GaN buffer layer is recrystallized under heat preservation for 6 minutes at 1,050 DEG C, the thickness of the non-doped GaN layer is 2.0-2.5 micrometers, the growth temperature of the non-doped GaN layer is 1,050 DEG C, the thickness of the doped N-type GaN layer is 2.5-3.0 micrometers, the Si doping concentration is 5*10<18>cm<-3>, the growth temperature is 1,050 DEG C, and the multi-quantum well AlGaN/GaN structure is formed by alternatively growing multi-quantum well AlGaN layers and multi-quantum well GaN layers according to six periods. By improving the crystal quality of an ultraviolet LED chip, the electron barrier effect of the electron barrier layer is optimized, the electron leakage is reduced, so that the efficiency reduction of an ultraviolet LED device is improved, and the light output power is improved.

The invention discloses a photoelectric detector and a photoelectric detection apparatus. A third electrode is arranged on one side, away from a first electrode and a second electrode, of a light sensing active layer. By applying voltage, different from the voltage of the first electrode or the second electrode, to the third electrode, electric field is at least formed between the third electrode and one of the first electrode and the second electrode, so the total electric field direction in the photoelectric detector is changed to other directions from the original horizontal direction, thereby changing an electron leakage channel. Therefore, dark current caused by a horizontal electric field can be reduced, and when the photoelectric detector carries out optical detection to generate light current, the contrast ratio of the light current to the dark current can be increased.

The invention belongs to the field of semiconductor photoelectric devices, and especially relates to a nitride light emitting diode assembly which can control size and density of V-shaped defects. Through arranging a first defect regulating layer, a second defect modulating layer, and a third defect modulating layer in sequence between an N-type layer and an active layer, the nitride light emitting diode assembly regulates problems of anti-static capacity reduction caused by more defects while regulating sizes and density of the V-shaped defects. Through synergistic effect of the three layersof regulating layers, sizes and density of the V-shaped defects are controlled, electron hole injection efficiency is improved, and meanwhile electron transfer rate is reduced and electron leakage isreduced, Efficiency Droop effect of a device is reduced, uniformity of distribution of the electron holes in the active layer is improved, non-radiation recombination radiation of the device is effectively reduced, and illuminating efficiency is improved.