Films etching

Fig. 4. XPS spectrum of (a) as-deposited Co2MnSi films and XPS spectra of Co2MnSi films etched for (b) 0.5 min, (c) 1 min...

Fig. 5. FESEM micrographs of Co2MnSi films etched in (a) 20% Cb/Ar, (b) 60% Cb/Ar, (c) 10% 02/10% Cb/Ar and (d) FESEM micrograph of etched MTJ stack arrays using TiN mask at 20% O2/10%Cb/Ar. TiN hard mask were used...

Figure 1. Cross sections of films etched with liquid or plasma etchants. The isotropic profile represents no overetch, and can be generated with liquid or plasma etch techniques. The anisotropic profile requires plasma...

This expression is independent of the film thickness. Thus, when one considers reflective monitoring of metal film etching, only at the interface between film and substrate will a change in reflectivity be observed due to the change in refractive index. Although this is extremely useful for end point detection one still must apply films of known thickness for cases in which etch rate information is desired. 

Liquid etching has been the preferred method for pattern delineation for thin films for many years (I). Its pervasive use has been due primarily to two considerations. First, although the exact chemistry is often poorly understood, the technology of liquid etching is firmly established. Second, the selectivity (ratio of film etch rate to the etch rate of the underlying film or substrate) can be essentially infinite with the proper choice of etchant solution. 

Table I. Properties of rf Glow Discharges (Plasmas) Used for Thin-Film Etching and Deposition...

Glow discharges or plasmas have been used extensively to promote chemical reactions for thin-film etching and deposition in a variety of technologically important areas. The reactive chemical atmosphere and complex discharge-surface interactions in these systems permit the attainment of unique etch profiles and film properties. 

Fig. 30a-c Topography a before b after developing the polymer film by immersing the surface for 10 s in methylethylketone at room temperature c cross sections of both topographies (black lines) reveal film etching down to the gold substrate (scan width 20 pm, z scale 166 nm (a) and 175 nm (b), 500x500 pixel)... 

Fig. 9. AES atomic concentration depth profile for a PBTMSS film on Au/Si. Film etched for 1 min. in a barrel reactor at 850 mTorr O2.

A second method of surface smoothing is to deposit a thick layer of SiOj and then a thin the layer by RIE or sputter etching. Because the sputter yield of the SiOj is greatest at an angle of 45°, the corners in the SiOj film etch quicker than the rest of the film and are therefore rounded by the etch process. With some deposition systems, for example, biased electron cyclotron resonance (ECR) plasma deposition, it is possible to deposit and etch concurrently, yielding a one-step process with a reduced deposition rate. ... 

Film Etch Rates. The etch rates of the SOG films were determined In various wet and dry media. The results are summarized In Table IV. 

The plasma etch rates of the SOG films were determined In an MRC Model 51 RIE parallel plate etcher which had 6 in. diameter electrodes. The electrode spacing was 2 in. and the substrates were placed on the powered electrode which was water cooled. The chamber pressure was about 200 mTorr for plasma etching and 10-15 mTorr for reaction ion etching (RIE). A net total power of 50W was used in each experiment. In contrast to their wet etch behavior, the SOG films etch only slightly faster than thermal Si02 in CF4 + O2 plasmas. This Is so since plasma etch rates are determined to a greater... 

This suggests that if there is a non-equivalency in etch rates, it is preferable that it be in favor of the CVD film etch rate. 

FM73 (rubber modified 120 °C curing film Etched aluminum 2,107 [14]... 

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