# US 11,307,235 B2 · In-tool ESD events selective monitoring method and apparatus

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,307,235 B2
- Document ID: US11307235B2
- Status: Granted
- Kind: B2
- Application number: 15/267,640
- Filed: 2016-09-16
- Published: 2017-05-11
- Granted: 2022-04-19
- Earliest claimed: 2012-12-28
- Assignees: Illinois Tool Works Inc.
- Applicants: Illinois Tool Works Inc.
- Inventors: Lyle D. Nelsen; Steven B. Heymann; Mark E. Hogsett
- Web page: https://patentgrep.com/patent/US11307235B2

## CPC

- G01R 31/001: {Measuring interference from external sources to, or emission from, the device under test, e.g. EMC, EMI, EMP or ESD testing (measuring electromagnetic fields G01R29/08; circuits for generating HV pulses in dielectric strength testing G01R31/14)}
- G01R 31/002: {where the device under test is an electronic circuit}
- G01R 31/2893: {Handling, conveying or loading, e.g. belts, boats, vacuum fingers (G01R31/2867 takes precedence; handling semiconductor devices or wafers during manufacture or treatment H10P72/00)}
- H02H 1/0007: {concerning the detecting means (in general G01R or other subclasses of G01; reed switches H01H71/2445)}
- G01R 35/005: {Calibrating; Standards or reference devices, e.g. voltage or resistance standards, "golden" references (G01R33/0035, G01R35/002 take precedence)}
- G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12)
- H02H: EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS (indicating or signalling undesired working conditions G01R, e.g. G01R31/00, G08B; locating faults along lines G01R31/08; emergency protective devices H01H)

## Abstract

An embodiment of the invention provides an apparatus for detecting electrostatic discharges (ESD) events, comprising: an ESD detector configured to determine at least one process window that will permit the ESD detector to detect an ESD event; at least one antenna coupled to said ESD detector; and said ESD detector calibrated for at least one discharge energy. Another embodiment of the invention provides: a method for detecting electrostatic discharges (ESD) events, comprising: determining at least one process window that will permit an ESD detector to detect an ESD event; and calibrating the ESD detector for at least one discharge energy.

## Claims

### Claim 1

An apparatus for detecting electrostatic discharges (ESD) events, the apparatus comprising:
an ESD detector comprising an attenuator, the ESD detector being configured to detect an ESD event;
a controller configured to:
activate a process window in response to a signal corresponding to a command to process a device being handled or tested by a tool;
activate the ESD detector to detect and report the ESD event occurring during the process window; and
deactivate the process window and control the ESD detector to enter into a standby mode to ignore electromagnetic signals in response a signal corresponding to a command to end the process; and
at least one antenna coupled to said ESD detector; wherein
said ESD detector is calibrated for at least one discharge energy threshold or range of discharge energies by adjusting the attenuator to suppress electromagnetic interference (EMI) outside the at least one discharge energy threshold or the range of discharge energies detected during the process window.

### Claim 2 (depends on 1)

The apparatus of claim 1, wherein the ESD detector is configured to measure a pulse duration of a received pulse in order to determine if the received pulse is an ESD event.

### Claim 3 (depends on 1)

The apparatus of claim 1, wherein the ESD detector is configured to reject a received pulse that is less than a first pulse duration or is greater than second pulse duration.

### Claim 4 (depends on 1)

The apparatus of claim 1, wherein the ESD detector is configured to reject a received pulse that is outside a frequency range.

### Claim 5 (depends on 1)

The apparatus of claim 1, wherein the ESD detector is configured to filter a received pulse based on a power, duration, and amplitude of the received pulse.

### Claim 6 (depends on 1)

The apparatus of claim 1, further comprising:
a charged device model event simulators (CDMES) unit comprising a first conductive part and a second conductive part;
wherein the first conductive part and the second conductive part differ in electrical potentials; and
wherein an input high voltage provides a charge to the first conductive part;
wherein the first conductive part is movable toward the second conductive part; and
wherein a CDM event is triggered as the first conductive part moves toward the second conductive part.

### Claim 7 (depends on 1)

The apparatus of claim 1, wherein the at least one antenna comprises characteristics that allow an ESD radiated energy to be directionally detected and suppress other events not of interest.

### Claim 8 (depends on 1)

The apparatus of claim 1, wherein the ESD event occurs in a tool process area.

### Claim 9 (depends on 8)

The apparatus of claim 8, wherein:
said tool process area comprises a first process area and a second process area;
said at least one antenna comprises a first antenna coupled to said ESD detector and a second antenna coupled to said ESD detector; and
said first antenna positioned in said first process area and said second antenna positioned in said second process area.

### Claim 10

A method for detecting electrostatic discharges (ESD) events, the method comprising:
calibrating the ESD detector for at least one discharge energy threshold;
activating, via a controller, a process window in response to a signal corresponding to a command to process a device being handled or tested by a tool;
activating the ESD detector to detect and report the ESD event occurring during the process window;
during the process window, detecting an ESD event via the ESD detector;
adjusting a signal to noise ratio via a signal to noise filter of the ESD detector to suppress electromagnetic interference (EMI) outside the least one discharge energy threshold detected during the process window; and
deactivating the process window via the controller and controlling the ESD detector to ignore electromagnetic signals based in part on the adjusted signal to noise ratio.

### Claim 11 (depends on 10)

The method of claim 10, wherein the ESD detector is configured to measure a pulse duration of a received pulse in order to determine if the received pulse is an ESD event.

### Claim 12 (depends on 10)

The method of claim 10, wherein the ESD detector is configured to reject a received pulse that is less than a first pulse duration or is greater than second pulse duration.

### Claim 13 (depends on 10)

The method of claim 10, wherein the ESD detector is configured to reject a received pulse that is outside a frequency range.

### Claim 14 (depends on 10)

The method of claim 10, wherein the ESD detector is configured to filter a received pulse based on a power, duration, and amplitude of the received pulse.

### Claim 15 (depends on 10)

The method of claim 10, further comprising:
triggering an ESD event as a first conductive part moves toward a second conductive part;
wherein the first conductive part and the second conductive part differ in electrical potentials; and
wherein an input high voltage provides a charge to the first conductive part; and
wherein the first conductive part is movable toward the second conductive part.

### Claim 16 (depends on 10)

The method of claim 10, further comprising:
allowing, by the at least one antenna, an ESD radiated energy to be directionally detected and suppressing, by the at least one antenna, other events not of interest outside the least one discharge energy threshold.

### Claim 17 (depends on 10)

The method of claim 10, wherein the ESD events occur in a tool process area.

### Claim 18 (depends on 17)

The method of claim 17, wherein:
said tool process area comprises a first process area and a second process area;
said at least one antenna comprises a first antenna coupled to said ESD detector and a second antenna coupled to said ESD detector; and
said first antenna positioned in said first process area and said second antenna positioned in said second process area.