Wafer cleaning issues at the wet process
Principle #7 – Nesting dolls – place one object inside another.
The idea that is generated from this principle is as follows.
Why do we use only one single nozzle? Why not shower? The shower has several halls – a lot of nozzles. More than that, we can make halls with different diameters in the center and in the periphery of the shower to ensure equal coverage of the disc with the chemistry.
So, the idea is to replace the single nozzle with the shower
11
Principle #13 – The other way around – Turn the object “upside-down”
This is a great tip. Indeed, why the disk is kept “face-up” during the washing process?
It would be much better to keep the disc “face down” to improve the removal of the defects from the surface.
So, the idea is to keep the wafer “face down” during the washing process
9
Principle #15 – Dynamism – change an object from rigid to movable or adaptive
The idea that is generated is as follows:
Replace the constant flow of the chemistry with variable flow, especially in the and of the process, to ensure defects removal from the disc.
So, the idea is to change (even make pulses) flow while the cleaning process.
6
Principle #16 – Partial or accessive action – do slightly more or slightly less
If 100 percent of an object is hard to achieve using a given solution method then, by using 'slightly less' or 'slightly more' of the same method, the problem may be considerably easier to solve.
A wafer is not contaminated equally: there are some areas with more defects and some areas with fewer amount of defects
The idea is to use the shower with a graduated flow - the more the defects the higher the flow
5
The general conclusion is to eliminate the system of the air supply and exhaust. Let air enter the chamber and convert exhaust to drain with very little under-pressure. The will stabilize the performance, reduce the cost and make the system more simple.
3
Improve the process to enhance the effectiveness of the cleaning with the chemistry
1
Improve the rinsing process to ensure the defects removal
0
Try to eliminate the wasting. Do we really need this?
0
To increase the density of the chemistry by temperature reduction
0
Prevent evaporation of the chemistry from the wafer
0
Increase the pressure in the chamber
0
The wafer is contaminated not equally. Use special cleaning on the areas that are more contaminated
0
מערכת כיווון אוטמיטת למסוע
לטבול את הצלחת במים במקום לשטוף אותה בכל פעם
Increase the temperature of the solution to make the process more effective
Define the more contaminated areas and spend more time/chemical to clean the specific areas
Similar projects
The process is related to microelectronics - microchip manufacturing. The purpose of the process is to create a SiO2 layer on the surface of a Si wafer. Equipment: Vertical furnace to heat the wafers in the Q2 atmosphere and perform oxidation on the wafer surface. Process: The oxidation occurs on the front side and on the back side of the wafer Requirements: Create a SiO2 thin layer with a certain thickness and low sigma - low standard deviation of the thickness between the wafers and within the wafer Failure: Wafers from the lower zone have higher thickness and significantly higher within wafer sigma (standard deviation of the thickness within the wafer)
This project investigates radial non-uniformity of CDO low-k dielectric deposited by PECVD and its possible impact on wafer performance. Final test data indicate that faster dies are mainly located closer to the wafer center, while slower dies are more often found near the wafer periphery. The corresponding RC-delay trend also increases toward the wafer edge. The focus of the project is the capacitance component of RC-delay. CDO is expected to provide a low dielectric constant between BEOL metal lines, but the deposited film may not have uniform properties across the wafer. Near the wafer edge, the process can be influenced by different gas flow, plasma behavior, residence time, temperature, and pumping conditions. This may lead to stronger oxidation and deeper precursor decomposition near the periphery, forming CDO that is more oxygen-rich, less carbon-rich, denser, and closer in behavior to SiO₂. As a result, the dielectric constant k may increase toward the wafer edge, causing higher interline capacitance, higher RC-delay, and lower die speed. The project uses Functional Modeling to understand how PECVD chamber components and process conditions affect CDO film properties. The goal is to identify the main functional and problematic interactions and propose directions for compensation, such as radial gas-flow tuning, multi-zone showerhead design, edge compensation flow, and local plasma or temperature control.
This project investigates the nonuniform erosion of an expensive Ta sputtering target during Ta/TaN PVD. A deep racetrack groove forces target replacement while a significant amount of tantalum remains unused. Using PRIZ problem-solving tools, the project explores the system’s functions, identifies the root causes of localized erosion, and develops ways to improve target utilization without reducing deposition rate or production throughput.