摘要:
This invention is directed to a method for rapid plasma etching of materials which are difficult to etch at a high rate. The method is particularly useful in plasma etching silicon nitride layers more than five microns thick. The method includes the use of a plasma source gas that includes an etchant gas and a sputtering gas. Two separate power sources are used in the etching process and the power to each power source as well as the ratio between the flow rates of the etchant gas and sputtering gas can be advantageously adjusted to obtain etch rates of silicon nitride greater than two microns per minute. Additionally, an embodiment of the method of the invention provides a two etch step process which combines a high etch rate process with a low etch rate process to achieve high throughput while minimizing the likelihood of damage to underlying layers. The first etch step of the two-step method provides a high etch rate of about two microns per minute to remove substantially all of a layer to be etched. In the second step, a low etch rate process having an etch rate below about two microns per minute is used to remove any residual material not removed by the first etch step.
摘要:
A two etchant etch method for etching a layer that is part of a masked structure is described. The method is useful, for example, in microelectrical mechanical system (MEMS) applications, and in the fabrication of integrated circuits and other electronic devices. The method can be used advantageously to optimize a plasma etch process capable of etching strict profile control trenches with 89°+/−1° sidewalls in silicon layers formed as part of a mask structure where the mask structure induces variations in etch rate. The inventive two etchant etch method etches a layer in a structure with a first etchant etch until a layer in a fastest etching region is etched. The layer is then etched with a second etchant until a layer in a region with a slowest etch rate is etched. A second etchant may also be selected to provide sidewall passivation and selectivity to an underlying layer of the structure.
摘要:
A two-step etch method for etching a masked layer or layers that include fast and slow etching regions is described. Fast and slow etching regions may arise in a variety of devices, such as microelectrical mechanical system (“MEMS”) applications and mixed signal (i.e. analog and digital) integrated circuits, as well as other integrated circuits and devices. In one embodiment, a first etchant is used to etch through the layer in the fastest etching region, and then a second etchant is used to complete etching through the layer in the slowest etching region.
摘要:
A two etchant etch method for etching a layer that is part of a masked structure is described. The method is useful, for example, in microelectrical mechanical system (MEMS) applications, and in the fabrication of integrated circuits and other electronic devices. The method can be used advantageously to optimize a plasma etch process capable of etching strict profile control trenches with 89°+/−1° sidewalls in silicon layers formed as part of a mask structure where the mask structure induces variations in etch rate. The inventive two etchant etch method etches a layer in a structure with a first etchant etch until a layer in a fastest etching region is etched. The layer is then etched with a second etchant until a layer in a region with a slowest etch rate is etched. A second etchant may also be selected to provide sidewall passivation and selectivity to an underlying layer of the structure.
摘要:
This invention is directed to a method for etching films on semiconductor substrates and cleaning etch chambers. The method includes an improved processing sequence and cleaning method where residue formed from processing a previous substrate are cleaned by the etching process used to remove an exposed layer of material from the present substrate. The process provides improved substrate throughput by combining the step to clean residue from a previous substrate with an etch step conducted on the present substrate. Applicants have found the method particularly useful in processing structures such as DRAM stacks, especially where the residue is formed by a trench etched in the previous silicon substrate and the exposed layer etched from the present substrate is silicon nitride.
摘要:
This invention is directed to a method for etching films on semiconductor substrates and cleaning etch chambers. The method includes an improved processing sequence and cleaning method where residue formed from processing a previous substrate are cleaned by the etching process used to remove an exposed layer of material from the present substrate. The process provides improved substrate throughput by combining the step to clean residue from a previous substrate with an etch step conducted on the present substrate. Applicants have found the method particularly useful in processing structures such as DRAM stacks, especially where the residue is formed by a trench etched in the previous silicon substrate and the exposed layer etched from the present substrate is silicon nitride.
摘要:
A process for etching a pattern-masked conductor substrate anisotropically so as to obtain very high etch rates comprising adding a polymer-forming fluorocarbon gas and an etch gas at high flow rates to an etch chamber at etching pressures of 77 millitorr to 100 Torr using a high source power and bias power to the substrate support electrode to form a high density plasma. The gases can be added together, sequentially or alternately.
摘要:
A method for controlling a profile of a structure formed on a substrate using nitrogen trifluoride (NF3) in a high density plasma (HDP) process. Changing the amount of NF3 in the plasma controls the profile of the structure. It has been found that the best results are obtained with an inductively coupled plasma wherein the ion density is at least 1012 ions/cm3. The method is particularly suited to etch processes such as deep trench etch in silicon wafers.
摘要:
A method for operating a plasma reactor to etch high-aspect-ratio features on a workpiece in a vacuum chamber. The method comprises the performance of an etch process followed by a flash process. During the etch process, a first gas is supplied into the vacuum chamber, and a plasma of the first gas is maintained for a first period of time. The plasma of the first gas comprises etchant and passivant species. During the flash process, a second gas comprising a deposit removal gas is supplied into the vacuum chamber, and a plasma of the second gas is maintained for a second period of time. The DC voltage between the workpiece and the plasma of the second gas during the second period of time is significantly less than the DC voltage between the workpiece and the plasma of the first gas during the first period of time.
摘要:
Thermo-optic devices including a bottom cladding layer, a patterned core material and a top cladding layer, each having a different refractive index, can be made by depositing a heater material, such as tungsten or chromium, on the outside of the bottom and/or top cladding layer. Depending on the refractive index differences between the cladding layers and the core layers, the amount of heater material can also be varied. The heater material can surround the cladding layers, can be present on the sidewalls and top only, or the sidewalls alone, to provide sufficient heat to change the refractive index of the layers and thus the path of light passing-through the device. These devices when built into the substrate can be connected to underlying devices for vertical integration, or connected to other devices and components formed on the same substrate for increased integration.