4results about How to "Uniform etching" patented technology

This disclosure includes the following steps: (a) forming an oxide SiGe film on the first side and an oxide Si film on the second side by oxidizing a first side of the SiGe layer and a second side of the Si layer respectively using a gas containing free radicalized oxygen; and (b) selectively etching the oxide SiGe film using hydrogen fluoride or a mixture of hydrogen fluoride and an inactive gas while maintaining the temperature of the semiconductor substrate above TL (°C) and below TH (°C). When the atomic ratio of Ge to Si in the SiGe layer is set to C (%) and the pressure or partial pressure of hydrogen fluoride in step (b) is set to P (Pa), C (%) < 25%, 50Pa ≤ P (Pa) ≤ 1000Pa, TL = 11.3 × LN (P) + 0.23 × C - 97.4, TH = 13 × LN (P) + C - 102.

The application provides a wafer etching method for etching a wafer with a P-type heavily doped substrate, the wafer etching method comprising: supplying an etching liquid with a preset temperature to the back surface of the wafer to etch the back surface of the wafer while the wafer is rotating, wherein the preset temperature is higher than normal temperature; stopping supplying the etching liquid to the wafer after a continuous duration, and then flushing the back surface of the wafer after the etching liquid stays on the back surface of the wafer for a preset duration. The wafer etching method provided by the application can realize uniform etching of the P-type heavily doped substrate wafer, thereby obtaining a thinned wafer product with the best appearance.

The present disclosure provides a kind of improved process stability light-emitting diode and its preparation method, belong to the field of optoelectronic manufacturing technology.The preparation method includes: growing epitaxial layer on substrate;Transparent conductive layer and barrier layer are formed in turn on the surface of the epitaxial layer away from the substrate;Mask is formed on the surface of the barrier layer, and the barrier layer is etched through the mask to form the etching window exposing the transparent conductive layer;The transparent conductive layer is wet etched through the etching window to form the patterned transparent conductive layer.The embodiment of the present disclosure can reduce the difficulty of preparing transparent conductive layer on micro light-emitting diode, improve process stability.

This utility model relates to the field of solar cell technology, specifically disclosing an etching apparatus. The apparatus includes: an etching unit comprising a substrate, wherein a liquid flow channel is provided on the substrate, the liquid flow channel having a supply port for providing etching solution and a drain port for discharging etching solution; and a liquid flow generating device configured to generate a liquid flow of etching solution, the liquid flow direction being from at least one of the supply ports into the liquid flow channel and from at least one of the drain ports out of the liquid flow channel. Compared with the prior art, the contact interface between the etching solution and the silicon wafer of this utility model is more uniform and stable, which can effectively improve etching uniformity, reduce over-etching rate, improve etching effect, and thus improve the performance and quality of the processed silicon wafer. At the same time, the overall structure of this utility model is simpler, the production precision requirements of the apparatus are lower, effectively reducing equipment costs and manufacturing difficulty, and facilitating industrial production.