Process monitor with statistically selected ring oscillator
First Claim
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1. A process monitor comprising:
- a test circuit formed on a product die having a distribution of cell types that is substantially identical to that of a plurality of circuits formed on the product die wherein the test circuit comprises a net chain delay circuit.
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Abstract
A process monitor includes a test circuit formed on a product die wherein the test circuit has a distribution of cell types that is substantially identical to that of the product die.
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5 Claims
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1. A process monitor comprising:
a test circuit formed on a product die having a distribution of cell types that is substantially identical to that of a plurality of circuits formed on the product die wherein the test circuit comprises a net chain delay circuit. - View Dependent Claims (5)
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2. A process monitor comprising:
a test circuit formed on a product die having a distribution of cell types that is substantially identical to that of a plurality of circuits formed on the product die wherein the test circuit has an average metal loading per stage that is substantially identical to that of the product die.
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3. A process monitor comprising:
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a test circuit formed on a product die having a distribution of cell types that is substantially identical to that of a plurality of circuits formed on the product die; and
a metal path having a length substantially equal to that of the test circuit for nulling out metal path delay.
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4. A process monitor comprising:
a test circuit formed on a product die having a distribution of cell types that is substantially identical to that of a plurality of circuits formed on the product die wherein the test circuit is routed to maximize metal path length for measuring the effects of over-etching and under-etching.
Specification