79results about How to "Improve electrical performance parameters" patented technology

The invention relates to a phosphorus gettering process of silicon chips in the manufacture of solar cells, which comprises the following steps: putting sueded silicon chips into a diffusion furnace for pre-deposition, removing a phosphorosilicate glass layer after diffusion, soaking the silicon chips through distributed processing in a hydrofluoric acid solution, and removing oxide layers from the surfaces of the silicon chips; then putting the silicon chips after washing into the diffusion furnace for secondary diffusion processing, taking the silicon chips out from the diffusion furnace after the processing of the secondary diffusion working procedure, cooling the silicon chips to room temperature, and measuring the square resistance of the silicon chips. The invention can effectively decrease heavily doped 'dead layers' and greatly prolong the average minority carrier lifetime of the silicon chips; after the processes including etching, PECVD, silk screen sintering and the like are finished according to the normal process of a cell chip, the average transformation efficiency of the made cell chip is further improved, and the cell chip has better electrical performance parameters.

The invention provides a groove type field effect transistor structure and a preparation method thereof. The preparation method comprises the steps: providing a substrate, forming an epitaxial layer, forming a device groove in the epitaxial layer, and forming a shielding dielectric layer, a shielding gate layer, a first isolation dielectric layer, a gate dielectric layer, a gate layer, a second isolation dielectric layer, a body region, a source electrode, a source electrode contact hole, a source electrode structure and a drain electrode structure. In the preparation process of the groove type field effect transistor structure, a self-alignment process is adopted, so that the pitch of a cell unit is not limited by the exposure capability of a photoetching machine and the alignment precision of the photoetching machine, the pitch of the cell unit of a device can be further reduced, the cell density is improved, the channel resistance of the device is reduced, and a device structure with stable electrical parameters and low characteristic on-resistance is obtained; by arranging a T-shaped source electrode structure, the contact area between a source electrode structure and a source and the contact area between the source electrode structure and the body region are increased, so that the contact resistance of the source can be effectively reduced, and the avalanche tolerance of the device is improved.