Non-contact, electrostatic, discharge detector

• US 5,315,255 A
• Filed: 07/16/1992
• Issued: 05/24/1994
• Est. Priority Date: 07/16/1992
• Status: Expired due to Term

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Bettinger, Michael J.
• Primary Examiner(s): Wieder, Kenneth A.
• Assistant Examiner(s): BROWN, GLENN WARNER
• Application Number:
  US07/914,784
• Time in Patent Office: 677 Days
• Field of Search: 324/72, 324/457, 324/458, 324/536, 324/109, 324/122, 324/123 R, 324/327
• US Class Current: 324/457
• CPC Class Codes: G01R 29/0814 Field measurements related to measuring influence on or from apparatus, components or humans EMC, EMI and similar testing in general G01R31/001, e.g. in ESD, EMI, EMC, EMP testing, measuring radiation leakage; detecting presence of micro- or radiowave emitters; dosimetry; testing shielding; measurements related to lightning
• CPC Class Codes: G01R 29/12 Measuring electrostatic fields or voltage-potential

Abstract

A small, portable, non-intrusive device that detects the occurrence of an electrostatic discharge (ESD) during the handling, transporting, and testing of static sensitive electronic parts. It can be used to locate grounding problems in assembly equipment and is useful during repairs and assembly of electronic equipment. A preferred use is in the manufacture of semiconductor devices and the equipment containing these devices which are sensitive to ESD occurrences.

Claims

1. A non-contact, electrostatic discharge event detector comprising:

a high impedance antenna input circuit to pass through a single-event signal and suppress a repeated background signal, said input circuit further comprising;

i. an antenna connecting to a blocking capacitor;

ii. a high impedance FET having an input in series with the blocking capacitor; and

iii. a first output coupling capacitor connecting to the FET;

b. amplification means to amplify said single-event signal; and

c. monitoring means to audit and record said single-event signal for detection and signature analysis.

2. The event detector as recited in claim 1 wherein the amplification means further comprises:

a. a biFET operational amplifier;

b. a second output coupling capacitor; and

c. an adjustable resistor having input from the second coupling capacitor.

3. The event detector as recited in claim 2 wherein the output means further comprises:

a. a power amplifier integrated circuit (IC);

b. an adjustable feedback means;

c. an output capacitor; and

d. a monitoring means connected to the power amplifier.

4. The event detector as recited in claim 3 wherein the monitoring means consists of earphones.

5. The event detector as recited in claim 3 wherein the monitoring means consists of a spectrum analyzer.

6. A non-contact, electrostatic discharge (ESD) event detector comprising:

a. an electrometer input circuit further comprising;

i. an antenna connecting to a blocking capacitor;

ii. a high-impedance FET having an input from the blocking capacitor; and

iii. a first output coupling capacitor connecting to the FET;

b. a second stage amplifier having an input from the first output coupling capacitor further comprising;

i. a biFET operational amplifier;

ii. a second output coupling capacitor; and

iii. an adjustable resistor having input from the second coupling capacitor;

c. a power amplifier having input from the adjustable resistor further comprising;

i. a power amplifier integrated circuit (IC);

ii. an adjustable feedback means; and

iii. an output capacitor;

d. a power supply; and

e. a monitoring means connected to the power amplifier wherein a local electrostatic discharge event is detected, amplified, and monitored by an operator.

7. The ESD event detector as recited in claim 6 wherein the monitoring means is a headphone.

8. The ESD event detector as recited in claim 6 wherein the monitoring means is a spectrum analyzer.

9. The ESD event detector as recited in claim 6 wherein the monitoring means is a sound amplifier system.