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What I am trying to understand is how the diode is placed inside of the encapsulating glass container such as that pictured in the following:

Glass Diode

I've tried to read some patents, where I more or less couldn't understand any of the language. How do manufacturers get the glass to encapsulate the actual semiconductor material without destroying it?

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    \$\begingroup\$ Comments are not for extended discussion; this conversation has been moved to chat. \$\endgroup\$
    – Dave Tweed
    Jun 22 '18 at 15:48
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The silicon wafer or bead can withstand 900’C but the critical process is the low temp interlayer powdered glass that is now Pb-free using Bismuth and other metals mixed with Silicon Dioxide. This passivation layer reduces the high temp leakage and limits most diodes to 200’C or less. The outer layer of glass is then molded with powdered SiO2 to form the shape that appears. The trade secrets are in the passivation blends of powder , cleaning processes and standard wire bonding to the melted gold bond to the crystal.

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    \$\begingroup\$ Like the new screen name :) \$\endgroup\$
    – Snoop
    Jun 22 '18 at 17:30
  • \$\begingroup\$ Thank you! I've been wondering about this on and off for years, googled it today, and now I know! \$\endgroup\$
    – user121934
    Jan 3 '20 at 22:10

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