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HPIM0602 | by jeri ellsworth
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This is an example of a "hand drawn" cmos inverter.


I started with steam thick oxide on a rectangular piece of wafer.


All the oxide cuts were made by carefully placing the etchant (no lithography)


Diffusion was done with carefully placed boron and phosphorous doping glass emulsion.


The contacts and gate electrode were conductive epoxy.


It had some interesting characteristics. Example 12v's pinch off on the p transistor and and n transistor that was slightly on between .0v and .1v gate voltage.


I won best of show. I was very proud, because it took me 2yrs to find a simple method to do this.


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Taken on November 28, 2007