What's All This Stuff About Germanium Diode Leakage?

If they look like Schottky diodes (small, orange glass packages), then they are Schottky. 1N60P are definitely Schottky. Most Schottky diodes are leaky, but not nearly as leaky as Germanium and their leakage current is not nearly as temperature-sensitive as Germanium. If the leakage current takes off when you touch the diode body, then that's a strong sign they are Germanium. Also, Ge diodes tend to have a higher forward resistance than Schottky or Silicon. I have a lot of Ge diodes with a higher Vf than 1N4148 when measured at 10mA.
 
Quick question - could you not use a current mirror to syphon off the leakage current? (at least from the operating point).
 
Most of the time, it's the AC leakage current that affects circuit performance. For example, in a BMP, the DC current in the diodes is zero because there is a series blocking cap. The AC leakage current reduces the gain of the soft clipping stages.
 
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