摘要:
The present invention relates to electrical contacts in a semiconductor device, and more particularly to methods and apparatuses for providing point contacts in a polysilicon emitter or HIT type solar cell. According to certain aspects, the invention uses a dielectric layer interposed between the substrate and a conductive layer to provide a limited area over which junction current can flow. The benefit is that the metal grid conductors do not need to align to the contacts, and can be applied freely without registration. Another benefit of the invention is that it provides increased efficiency for poly emitter and HIT cells through use of point contacts to increase current density. A further benefit is that patterning can be accomplished using low cost methods such as inclusion masking, screen printing or laser ablation. A still further benefit is that final contacts do not need alignment to the point contacts, eliminating registration required for conventional point contact designs.
摘要:
Embodiments of the invention contemplate the formation of a high efficiency solar cell using a novel plasma oxidation process to form a passivation film stack on a surface of a solar cell substrate. In one embodiment, the methods include providing a substrate having a first type of doping atom on a back surface of the substrate and a second type of doping atom on a front surface of the substrate, plasma oxidizing the back surface of the substrate to form an oxidation layer thereon, and forming a silicon nitride layer on the oxidation layer.
摘要:
A method of manufacturing a solar cell is provided. One surface of a semiconductor substrate is doped with a n-type dopant. The substrate is then subjected to a thermal oxidation process to form an oxide layer on one or both surfaces of the substrate. The thermal process also diffuses the dopant into the substrate, smoothing the concentration profile. The smoothed concentration gradient enables the oxide layer to act as a passivating layer. Anti-reflective coatings may be applied over the oxide layers, and a reflective layer may be applied on the surface opposite the doped surface to complete the solar cell.
摘要:
A simplified manufacturing process and the resultant bifacial solar cell (BSC) are provided, the simplified manufacturing process reducing manufacturing costs. The BSC includes an active region located on the front surface of the substrate, formed for example by a phosphorous diffusion step. The back surface includes a doped region, the doped region having the same conductivity as the substrate but with a higher doping level. Contact grids are formed, for example by screen printing. Front junction isolation is accomplished using a laser scribe.
摘要:
A simplified manufacturing process and the resultant bifacial solar cell (BSC) are provided, the simplified manufacturing process reducing manufacturing costs. The BSC includes an active region located on the front surface of the substrate, formed for example by a phosphorous diffusion step. After removing the PSG, assuming phosphorous diffusion, and isolating the front junction, dielectric layers are deposited on the front and back surfaces. Contact grids are formed, for example by screen printing. Prior to depositing the back surface dielectric, a metal grid may be applied to the back surface, the back surface contact grid registered to, and alloyed to, the metal grid during contact firing.
摘要:
A method for fabricating point contacts to the rear surface of a silicon solar cell by coating the rear surface with a masking layer and a laser absorptive layer and directing laser radiation to the rear surface to form openings therein after which doping material is applied through the openings and contacts are applied. The doping is preferably performed by plasma immersion ion implantation.
摘要:
Critical Dimension (CD) of features on a semiconductor substrate may be indicated utilizing the site-specific binding properties of organic or biological molecules. In accordance with one embodiment of the present invention, a fluorescent tagged organic molecule is fabricated having a length corresponding to the desired CD. The semiconductor substrate is exposed to a solution containing the organic molecule. The solution is then removed and the structure analyzed for the presence of the fluorescent tag, indicating a feature having the desired CD. Fluorescent tagged biological molecules of known size such as peptides or proteins, or nucleic acids such as DNA or RNA, may also be employed for CD measurement. Alternatively, a CD marker molecule may be designed to exhibit preferential binding, such that it fails to bind to the substrate in instances of incomplete resist development or etching.
摘要:
A coefficient of a function that relates a measurement from a wafer to a parameter used in making the measurement (such as the power of a beam used in the measurement) is determined. The coefficient is used to evaluate the wafer (e.g. to accept or reject the wafer for further processing), and/or to control fabrication of another wafer. In one embodiment, the coefficient is used to control operation of a wafer processing unit (that may include, e.g. an ion implanter), or a heat treatment unit (such as a rapid thermal annealer).
摘要:
A particle sensor which employs the principle that a particle passing through an intense laser beam will scatter light to a photodetector which then generates a measurable signal is provided. The particle sensor uses prisms and a cylindrical lens to compress the laser beam to make it very thin along the axis of particle motion but very wide in the plane perpendicular to particle motion, thereby simultaneously providing high beam intensity for enhanced sensitivity and a large detection area. The optical components of the sensor are mounted on separate sections which allows the optical components to be separately aligned and changed so that the sensor may be easily adapted to various applications.
摘要:
A housing for a laser based particle monitor comprising a pair of pipes for directing particle flow through a chamber. In one embodiment, elbows are disposed on the piping such that the interior of the chamber cannot be viewed from a point outside the housing.