Abstract: A simulation method of CMP process comprises: building a CMP model, and forming a matrix table of line width logarithm-density according to the CMP model, and making each intersection of the matrix table correspond to each CMP result under the corresponding line width and density; dividing a layout into a plurality of grids, and converting the equivalent line width and density of each grid into the coordinate of line width logarithm-density in the matrix table; fitting and calculating preliminary CMP simulation results of each grid according to the coordinate of each grid in the matrix table and the CMP simulation results of its adjacent intersections of the matrix table; fitting and computing final CMP simulation results of each grid according to a related weighting factor which considers the impact of adjacent grids for the current grid on the layout; outputting the final CMP simulation results of the whole layout.

Abstract: The invention disclosed a method for forming high aspect ratio patterning structure. Firstly, forming a dielectric film ashing stop layer, a first photoresist layer, a first hard mask layer and a second photoresist layer on a semiconductor substrate in turn. A second hard mask layer having a high etch selectivity ratio with the first photoresist layer is formed on top surface and sidewall of the pattern by utilizing a low temperature chemical vapor deposition process, which can be a protect for the pattern sidewall during the later etching process of the first photoresist layer. So, the cone-shaped or the bowling-shaped photoresist morphology caused by plasma bombardment can be avoided. Therefore, the problems of the insufficient of selectivity ratio, burrs at the edge of the pattern and larger critical dimension can be solved, and the implanted ions can be well distributed according to the design of the device.

Abstract: The invention disclosed a method for forming high aspect ratio patterning structure. Firstly, forming a dielectric film ashing stop layer, a first photoresist layer, a first hard mask layer and a second photoresist layer on a semiconductor substrate in turn. A second hard mask layer having a high etch selectivity ratio with the first photoresist layer is formed on top surface and sidewall of the pattern by utilizing a low temperature chemical vapor deposition process, which can be a protect for the pattern sidewall during the later etching process of the first photoresist layer. So, the cone-shaped or the bowling-shaped photoresist morphology caused by plasma bombardment can be avoided. Therefore, the problems of the insufficient of selectivity ratio, burrs at the edge of the pattern and larger critical dimension can be solved, and the implanted ions can be well distributed according to the design of the device.

Abstract: The invention disclosed a method for forming shallow trenches of the dual active regions. Firstly, forming an etch stop layer on a semiconductor substrate; secondly, using a first accurate photomask to expose and develop the semiconductor substrate, until the etch stop layer has been exposed on the top of the first shallow trench regions and the second shallow trench regions; thirdly, etching the etch stop layer entirely in the exposed regions; fourthly, using a second photomask to expose and develop the first shallow trench regions which require a deeper etch depth of the trench than that of the second shallow trench regions; fifthly, etching and forming preliminary entirely depth in the first shallow trench regions, and then removing the second photomask; at last, taking the etch stop layer as a mask, and simultaneously etching the first shallow trench regions and the second shallow trench regions to form the first hallow trenches and the second shallow trenches having different depths.

Abstract: The invention disclosed a simulation method of CMP process, comprising: firstly, building a CMP model, and forming a matrix table of line width logarithm-density according to the CMP model, and making each intersection of the matrix table correspond to each CMP result under the corresponding line width and density; secondly, dividing a layout into a plurality of grids, and converting the equivalent line width and density of each grid into the coordinate of line width logarithm-density in the matrix table; thirdly, fitting and calculating preliminary CMP simulation results of each grid according to the coordinate of each grid in the matrix table and the CMP simulation results of its adjacent intersections of the matrix table; then, fitting and computing final CMP simulation results of each grid according to a related weighting factor which considers the impact of adjacent grids for the current grid on the layout; finally, outputting the final CMP simulation results of the whole layout.

Abstract: The invention disclosed a method for forming shallow trenches of the dual active regions. Firstly, forming an etch stop layer on a semiconductor substrate; secondly, using a first accurate photomask to expose and develop the semiconductor substrate, until the etch stop layer has been exposed on the top of the first shallow trench regions and the second shallow trench regions; thirdly, etching the etch stop layer entirely in the exposed regions; fourthly, using a second photomask to expose and develop the first shallow trench regions which require a deeper etch depth of the trench than that of the second shallow trench regions; fifthly, etching and forming preliminary entirely depth in the first shallow trench regions, and then removing the second photomask; at last, taking the etch stop layer as a mask, and simultaneously etching the first shallow trench regions and the second shallow trench regions to form the first hallow trenches and the second shallow trenches having different depths.

Abstract: A method of etching a shallow trench is disclosed in the present invention. By removing the photoresist layer immediately at the end point of the hard mask layer etching and further using the improved process conditions etch the top of the substrate at the same time of the hard mask layer over-etching, such as a lower bias power, a higher pressure and a bigger polymer gases flow rate, the present invention has formed a smooth morphology on the top of the shallow trench. Therefore, the sharp corner appeared in the prior art is avoided by changing the start point of the silicon substrate etching, so as to fundamentally eliminate the leakage current caused by the sharp corner.

Abstract: The present invention provides a method for controlling a critical dimension of shallow trench isolations in a STI etch process, comprises the following steps: before the STI etch process, pre-establishing a mapping relation between a post-etch and pre-etch critical dimension difference of a BARC layer and a thickness of the BARC layer; and during the STI etch process after coating the BARC layer, measuring the thickness of the BARC layer and determining a trimming time for a hard mask layer according to a critical dimension difference corresponding to the measured thickness in the mapping relation and a critical dimension of a photoresist pattern, then performing a trimming process for the hard mask layer lasting the trimming time to make a critical dimension of the hard mask layer equal to a required critical dimension of an active area, and etching a substrate to form shallow trenches with a predetermined critical dimension.

Abstract: The present invention provides a method for controlling a critical dimension of shallow trench isolations in a STI etch process, comprises the following steps: before the STI etch process, pre-establishing a mapping relation between a post-etch and pre-etch critical dimension difference of a BARC layer and a thickness of the BARC layer; and during the STI etch process after coating the BARC layer, measuring the thickness of the BARC layer and determining a trimming time for a hard mask layer according to a critical dimension difference corresponding to the measured thickness in the mapping relation and a critical dimension of a photoresist pattern, then performing a trimming process for the hard mask layer lasting the trimming time to make a critical dimension of the hard mask layer equal to a required critical dimension of an active area, and etching a substrate to form shallow trenches with a predetermined critical dimension.

Abstract: A method integrating target optimization and optical proximity correction including: fragmenting sides of a target pattern in the metal layer to form a plurality of fragments; simulating the target pattern and calculating image log slope of each fragment; calculating a target pattern optimal parameter for each fragment which is a product of three parameters including the image log slope, overlap ratio of the target pattern and a via pattern in a via layer, and critical dimension; optimizing the target pattern based on the target pattern optimal parameter; preforming optical proximity correction to the optimized target pattern; determining whether the corrected target pattern meets requirements; if yes, ending the target optimization and optical proximity correction; otherwise, using the corrected target pattern as a current target pattern and iterate from the step of simulating the target pattern and calculating image log slope of each fragment.

Abstract: A method for etching a polysilicon gate is disclosed, wherein the polysilicon gate includes an undoped polysilicon portion and a doped polysilicon portion that is situated on the undoped polysilicon portion. The method includes: obtaining a thickness of the undoped polysilicon portion and a thickness of the doped polysilicon portion by using an optical linewidth measurement device; and etching the undoped polysilicon portion and the doped polysilicon portion by using two respective steps with different parameters, respective etching time for the undoped polysilicon portion and the doped polysilicon portion of every wafer being adjusted in real time by using an advanced process control system. This method enables the doped and undoped polysilicon portions of each polysilicon gate on every wafer to have substantially consistent profiles between each other.

Abstract: A high voltage bipolar transistor with shallow trench isolation (STI) comprises the areas of a collector formed by implanting first electric type impurities into active area and connected with pseudo buried layers at two sides; Pseudo buried layers which are formed by implanting high dose first type impurity through the bottoms of STI at two sides if active area, and do not touch directly; deep contact through field oxide to contact pseudo buried layers and pick up the collectors; a base deposited on the collector by epitaxial growth and in-situ doped by second electric type impurity, in which the intrinsic base touches local collector and extrinsic base is used for base pick-up; a emitter which is a polysilicon layer deposited on the intrinsic base and doped with first electric type impurities. This invention makes the depletion region of collector/base junction from 1D (vertical) distribution to 2D (vertical and lateral) distribution.

Abstract: The present invention discloses a method for reducing the morphological difference between N-doped and undoped poly-silicon gates after etching, comprising the following sequential steps: depositing a hard mask layer on a substrate template having N-doped poly-silicon and undoped poly-silicon to form an N-doped poly-silicon hard mask layer and an undoped poly-silicon hard mask layer respectively, and etching the undoped poly-silicon hard mask layer to make a thickness difference between the N-doped poly-silicon hard mask layer and the undoped poly-silicon hard mask layer; depositing an anti-reflection layer, and etching according to a predetermined pattern until exposing the N-doped poly-silicon, wherein when the N-doped poly-silicon is exposed, the undoped poly-silicon is etched to a certain degree; and removing residuals on the surface of the above formed structure, and etching to form an N-doped poly-silicon gate and an undoped poly-silicon gate, respectively.

Abstract: The present invention discloses a method for reducing the morphological difference between N-doped and undoped poly-silicon gates after etching, comprising the following sequential steps: depositing a hard mask layer on a substrate template having N-doped poly-silicon and undoped poly-silicon to form an N-doped poly-silicon hard mask layer and an undoped poly-silicon hard mask layer respectively, and etching the undoped poly-silicon hard mask layer to make a thickness difference between the N-doped poly-silicon hard mask layer and the undoped poly-silicon hard mask layer; depositing an anti-reflection layer, and etching according to a predetermined pattern until exposing the N-doped poly-silicon, wherein when the N-doped poly-silicon is exposed, the undoped poly-silicon is etched to a certain degree; and removing residuals on the surface of the above formed structure, and etching to form an N-doped poly-silicon gate and an undoped poly-silicon gate, respectively.

Abstract: A high voltage bipolar transistor with shallow trench isolation (STI) comprises the areas of a collector formed by implanting first electric type impurities into active area and connected with pseudo buried layers at two sides; Pseudo buried layers which are formed by implanting high dose first type impurity through the bottoms of STI at two sides if active area, and do not touch directly; deep contact through field oxide to contact pseudo buried layers and pick up the collectors; a base deposited on the collector by epitaxial growth and in-situ doped by second electric type impurity, in which the intrinsic base touches local collector and extrinsic base is used for base pick-up; a emitter which is a polysilicon layer deposited on the intrinsic base and doped with first electric type impurities. This invention makes the depletion region of collector/base junction from 1D (vertical) distribution to 2D (vertical and lateral) distribution.