Method to solve alignment mark blinded issues and technology for application of semiconductor etching at a tiny area

A drop etcher apparatus, comprising:

• a control unit;
• a dispenser tube having:
• an upper end;
• a semiconductor structure;
• and a lower tip proximate an upper surface of the semiconductor structure;
• a chemical reservoir partially filled with a chemical within the dispenser tube;
• the chemical reservoir having an initial upper surface;
• and
• a dispenser line comprising a pressurized gas connecting the control unit to the upper end of the dispenser tube, wherein the control unit controls a flow of the pressurized gas to dispense a predetermined amount of a drop of the chemical to remove blinded alignment marks of the upper surface of the semiconductor structure, wherein the predetermined amount of the drop is dispensed through the lower tip of the dispensing tube to the upper surface of the semiconductor structure by exertion of pressure from the gas flowing through the dispenser line to the initial upper surface of the chemical reservoir;
• a filter interposed in the dispenser line through which the gas flows to filter the gas;
• a pressure regulator interposed in the dispenser line through which the gas flows to regulate the pressure of the gas;
• and
• a high-speed shut-off valve interposed in the dispenser line through which the gas flows to regulate the flow of the gas, wherein the high-speed shut-off valve has a radius, and wherein the pressure regulator, the high speed shut-off valve, and the filter are external to the control unit;
• wherein the upper surface of the semiconductor structure comprises an alignment mark area and a cell area, wherein the alignment mark area is spaced apart from a shallow trench isolation opening of the cell area, and wherein the lower tip of the dispensing tube is aligned with the blinded alignment marks of the alignment mark area.