34results about How to "Reduce recombination current" patented technology

The invention provides a method for preparing an N-type crystalline silicon solar cell with aluminum-based local emitters on the back side. The method comprises the following steps: firstly, selecting N-type silicon wafers to carry out the surface-textured etching process; further forming a front surface field through phosphorous diffusion; depositing a passivating film on the front surface after the phosphorosilicate glass is formed during the removal of diffused phosphorous; carrying out the back-side chemical polishing process on the silicon wafers to remove the N+ layer formed on the back side during the phosphorous diffusion; then, sequentially printing an aluminum layer or a silver-aluminum layer through the passivating film deposited on the back side, local holes or grooves on the back side and screens on the back side; then, printing silver paste on the front surface; and finally, carrying out the one-step sintering process to form a local P+ layer on the back side and allowing the P+ layer to coming into ohmic contact with the electrodes on the front and back surfaces. By using the N-type substrate, forming local aluminum-based P-N junctions on the back side and further using the back-side chemical polishing process to remove the edge junctions, the invention can substitute for the conventional stacking-type plasma etching process, simplify the technological procedures and further bring a series of performance improvement to cells.

The invention discloses a method of producing SiGe HBT transistors, which includes steps of reducing the doping concentration of emitter polysilicon, controlling the undercut dimension of an emitter window, increasing the thickness of an emitter monocystal silicon layer, and increasing the final activation temperature of devices, thereby maintaining bases out of highly defective areas and further greatly reducing the base recombination current.

The invention relates to a passivation contact solar cell with a selective emitter structure and a preparation method of the passivation contact solar cell. The method comprises the following steps: (1) preparing texturing surfaces on two surfaces of an N-type crystalline silicon substrate; (2) performing boron diffusion treatment on the texturing surface of the front surface of the substrate to form a lightly doped region layer; (3) performing local boron ion implantation on the lightly doped region layer by using a mask, and annealing to form a local heavily doped region; (4) preparing a tunneling oxide layer on the texturing surface of the back surface of the substrate, and preparing a phosphorus-doped polycrystalline silicon layer on the tunneling oxide layer; (5) preparing a silicon nitride antireflection layer on the phosphorus-doped polycrystalline silicon layer; preparing an aluminum oxide passivation layer on the lightly doped region layer on the front surface of the substrate, and preparing a silicon nitride antireflection layer on the aluminum oxide passivation layer; and (6) carrying out silk-screen printing of metallized slurry on the two surfaces of the substrate, andsintering. According to the invention, the composite current on the surface of the emitter can be remarkably reduced, so that the efficiency of the N-type passivation contact battery can be improvedby more than 0.2%.

The present invention aims at providing a heterojunction bipolar transistor having improved breakdown voltage on operation for high power output, and includes: a GaAs semiconductor substrate 100; an n⁺-type GaAs sub-collector layer 110; an n-type GaAs collector layer 120; a p-type GaAs base layer 130; an emitter layer 140; an n-type GaAs emitter cap layer 150; and an n-type InGaAs emitter contact layer 160. The emitter layer 140 has a multilayer structure including an n-type or non-doped first emitter layer 141 and an n-type second emitter layer 142 which are laminated in sequence. The first emitter layer 141 is made of a semiconductor material including Al, while the second emitter layer 142 is made of In_xGa1-xP (0<x<1).

The invention discloses a gate line structure making local contact with the obverse surface of a solar battery and a manufacturing method of the gate line structure. The gate line structure making local contact with the obverse surface of the solar battery is provided with a plurality of gate line electrodes. Each gate line electrode is provided with a plurality of local contact metal electrodes and a plurality of non-contact metal electrodes. The local contact metal electrodes are electrically connected with the non-contact metal electrodes. The non-contact metal electrodes are made of non-burnthrough metal electrode paste. The local contact metal electrodes penetrate through a dielectric film of the battery and then make ohmic contact with a silicon substrate. According to the gate line structure, it can be guaranteed that under the condition of avoiding electron transport, the metalized area is effectively reduced, and recombination current of a metalized area is reduced; accordingly, open-circuit voltage of the battery is effectively increased, and the conversion efficiency of the solar battery is improved.

The invention relates to a method for surface corrosion of a CdTe film and preparation of a CdTe solar cell by adopting the method, pertaining to the processing field of semiconductor devices. An mixed liquid of nitric acid, glacial acetic acid, NaAc and deionized water is served as corrosive liquid, wherein, the NaAc is served as a buffering agent to keep the pH value of the intermixture unchanged and lead the reaction to be more stable; CdTe and the nitric acid react to generate a layer rich in tellurium; after washing and blow-drying, a back contact layer containing Cu or without Cu is sedimented; finally, a back electrode is sedimented for preparing the CdTe solar cell. Sedimentation of back contact material can increase carrier concentration near a pn junction, reduce the height of Schottky potential barrier and avoid direct sedimentation of Cu from forming a comparatively complex CuxTe structure. By adopting the method for corrosion and the preparation of the CdTe solar cell, the performance of the solar cell can be obviously improved and the stability and the repeatability of the device can be ensured.

The invention discloses a method for implementing a base region window of a silicon germanium heterojunction transistor, which comprises the following steps of: depositing a composite dielectric film on a silicon chip with an embedded layer, a collector region and a substrate isolation region on a silicon substrate; performing dry etching on the composite dielectric film, defining the base regionwindow, and etching an oxide film stopped on the composite dielectric film; after the base region window is opened and before the oxide film of the composite dielectric film is removed, depositing a dielectric film layer, and forming a D-shaped side wall at the interface step of the base region window by using the dielectric film layer; and meanwhile, performing wet removal on the residual oxide film in the base region window by using the protection of the D-shaped side wall, and epitaxially growing an SiGe base region. The interface step of the base region window is changed slowly because ofthe formation of the D-shaped side wall, and the slowly changed step formed by the D-shaped side wall is continuously reserved after SiGe extension and has no insulator residue in the subsequent emitter polycrystalline silicon side wall process, so that continuous metal silicide is formed, the resistance of an outer base region is reduced, and the performance of the device is improved.

The invention provides a manufacturing method of a MWT (Metal Wrap Through) solar battery. The method comprises the steps of: providing a substrate which comprises a body layer, a reflection-reducing layer and a passivation layer, wherein a plurality of through holes and openings are arranged on the substrate; forming conductive electrodes in the through holes and forming a first back contact electrode on the back of the substrate; forming second back contact electrodes in the openings; forming a touch grid line electrode on the front face of the substrate; sintering the substrate so that the touch grid line electrode is electrically connected with the conductive electrode; and forming a local front surface field in the front surface of the body layer; and forming a local back emitting electrode in the back surface of the substrate. The MWT solar battery manufactured by the method is small in composite current, large in light receiving area and high in photoelectric conversion efficiency, and the problem that the battery is bended is reduced. In addition, according to the manufacturing method provided by the invention, steps such as diffusive knot manufacture, edge corrosion, glass layer removal and secondary clean in conventional process are avoided, so that the manufacturing process flow is simplified and the production cost is reduced.

The invention discloses a manufacture method for a twin pole device resisting low dosage rate irradiation. According to the invention, a multi-layer passivation structure employing PSG (Phosphorosilicate Glass) + SiO2 double-layer electrode isolation medium and SiO2+BPSG (Boron Phosphorosilicate Glass)+SiO2. By adopting the above structure, total number of defects in the electrode isolation medium layer is reduced substantially on one hand. On the other hand, through adsorption of positive charges of the PSG and the BPSG, accumulation of the positive changes generated in the irradiation environment on the surface of Si-SiO2 is prevented and further the low dosage rate irradiation resistance of the twin-pole device is improved. The manufacture method provided by the invention is simple in technical procedure and is compatible to Si manufacture technique that is widely applied currently, and can be used for manufacturing the twin pole device having low dosage rate irradiation resistance.

The invention discloses a solar cell with a back local area doped heavily. The solar cell comprises a silicon base layer; a metallization area is arranged on the back surface of the silicon base layer; and a local heavily doped area is arranged in the metallization area. The invention provides the solar cell with the back local area doped heavily and a preparation method thereof. The invention discloses a technical method adopting two-time laser treatment. The first-time laser treatment aims to ablate a back passivation dielectric film of the metallization area to expose the silicon surface ofa bottom layer, and then the second-time laser treatment is carried out after doped slurry is printed in open film areas; the second-time laser treatment aims to push doping elements in the doped slurry into a silicon wafer, and then local area heavy doping is formed in the metallization area on the back surface of the solar cell; and then, a metallization process is carried out to complete the preparation of the solar cell with the back local area doped heavily. Therefore, the composite current of the metallization area on the back surface of the solar cell is reduced, and the contact resistance is reduced.

The present invention discloses a preparation method of an IBC solar cell. The method comprises the steps of: performing texture surface making and texturing of a silicon substrate, and performing double-sided preparation of a mask layer; performing back surface laser etching opening, and performing boron diffusion to form a back surface emitting electrode; performing laser doping to form a heavydoping selectivity emitting electrode area; removing the double-sided mask layer and a borosilicate glass layer; performing double-sided preparation of a mask layer, performing back surface laser etching opening, and performing phosphorus diffusion to form a back surface field; removing the double-sided mask layer and a phosphorosilicate glass layer; performing double-sided preparation of a passivation layer and an anti-reflection layer; and performing double-sided preparation of a metal electrode, and obtaining an IBC solar cell. The preparation method of an IBC solar cell is simple in preparation process, simplifies the cell preparation process, can avoid damaging of the silicon substrate, can improve the production efficiency and can greatly reduce the recombination current of the emitting electrode.

The invention belongs to the technical field of semiconductor photoelectric detectors, and particularly relates to a monolithic integrated nBnBn four-waveband detector, which adopts a longitudinal integrated structure. The monolithic integrated nBnBn four-waveband detector comprises a GaSb substrate, an n-type short-wave channel ohmic contact layer, a first metal electrode layer, a short-wave channel absorption layer, a first barrier layer, a medium-wave channel absorption layer, an n-type medium-wave channel contact layer, a common electrode layer, a long-wave channel absorption layer, a second barrier layer, an ultra-long-wave channel absorption layer, an n-type ultra-long-wave channel contact layer, a second metal electrode layer and a passivation layer. The detector with four wave bands in the detector has an integrated structure from bottom to top, has a four-absorption-layer structure, can respectively detect the four wave bands through voltage control, has the advantages of highresponsivity, low dark current and the like, reduces the false alarm rate, reduces the size of a device, and reduces the complexity of a preparation process and a detection system.