Chemical mechanical planarization devices

Lee SM, Mahajan V, Chen Z, Singh RK. Chemical mechanical planarization in IC devices, manufacturing III. Proc Electrochem Soc 2000 99-37 187-192. 

As a result of a ubiquitous society, displays for electronic appliances such as mobile computers and mobile phones demand high efficiency. High efficiency electronics were realized with the advent of nanoscale devices. Especially for nanoscale devices, the importance of the chemical-mechanical planarization (CMP) process emerged to achieve the integration and multilevel interconnections. The CMP process supports increasing capacity. 

A new method was developed using a modified polishing device for measuring galvanic corrosion during chemical mechanical planarization (CMP) of copper and tantalum [22]. CMP is used to pofish on a microscopic scale. In most cases, this is done using a colloidal slurry of abrasive microscopic particles. 

Typical microfabrication processes include the following steps wafer cleaning, photolithography, etching, thin film deposition, doping (by either thermal diffusion or ion implantation), bonding (wire and wafer bonding), and chemical-mechanical planarization (CMP).The complexity of microfabrication processes can be described by their mask count. This one represents the number of different pattern layers that will constitute the final device. Modem microprocessors are made with 30 masks while a few masks suffice for a microfluidic device or a laser diode. 

Bomcki, L., Sampumo, Y., Philipossian, A., (Araca incorporated), 2014b. Method and Device for the Injection of Chemical Mechanical Planarization Slurry. Korean patent, 1394745. Granted July 2014. 

By its virtue, chemical mechanical planarization (CMP) is a subtractive manufacturing process that polishes off overburden material as exemplified in Figure 17.3. So, naturally, once finished, it will reveal all the feamres underneath, circuits and defects alike. Also, in the semiconductor process flow, CMP is usually the terminal downstream process that completes the definition of a device or circuit. As a consequence, not only does it generate defects of its own, but it can also modulate defects from upstream processes. Therefore, the post-CMP defect target is usually the most stringent along the entire process flow because at this stage, defects have the most direct impacts on yield and reliability. 

Applications of chemical mechanical planarization (CMP) to More than Moore devices... 

Normally the surface of the deposited layers requires planarization to make the surface completely parallel to the substrate before the deposition of the next layer. This is critical because any curved or warped layer will compromise device integrity. For the planarization of the layers, polishing compounds in a form of a powder slurry have been used. The abrasive powders remove unnecessary parts of the layers by the synergistic effect of both physical and chemical forces and hence the process is called chemical-mechanical planarization (CMP). 

With the decrease of device dimensions, planarization of both front and back end layers by chemical mechanical polishing (CMP) now seems an absolute must for technologies smaller than 0.5 m. Unfortunately, CMP... 

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