Probe Tip Position Correction for Thermal Expansion in Chip Inspection

Solution Overview

Problem

Conventional probe apparatuses face inefficiencies and reliability issues during high-temperature and low-temperature inspections due to thermal expansion of probe cards, leading to misalignment and potential damage to probes and target objects, as they require preheating or cooling and struggle to maintain precise contact.

Innovation Solution

An inspecting method that registers and corrects the tip positions of probes based on contact time with a target object at a predetermined temperature, allowing for stable inspection without preheating or cooling the probe card, thereby maintaining accurate alignment and reducing overdrive pressure.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If the target object is heated to high temperature for inspection, then the electrical characteristics at high temperature can be measured, but the probe card and probes experience thermal expansion causing misalignment and potential damage

Engineering Contradiction:

Improveinspection temperatureVSAvoidprobe alignment precision

Core Design Contradiction:

TemperatureVSManufacturing precision

Solution Approach 1:

The probe card is preheated to the inspection temperature before the target object is brought into contact with the probes. This preliminary thermal treatment prevents thermal expansion during inspection, maintaining precise alignment between probes and electrode pads throughout the measurement process

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The conventional method of gradually heating the target object during inspection is replaced by rapidly preheating the probe card before contact. This rushes through the thermal equilibrium process in advance, eliminating gradual thermal expansion that would cause alignment drift during measurement

Inventive Principle:

Principle #21Skipping (Rushing through)

2Manufacturing precision

If the probe card is preheated before inspection, then alignment precision is maintained, but the inspection time is increased due to the preheating process

Engineering Contradiction:

Improveprobe alignment precisionVSAvoidinspection time

Core Design Contradiction:

Manufacturing precisionVSLoss of time

Solution Approach 1:

The probe card is preheated to the inspection temperature before the target object is brought into contact with the probes. This preliminary thermal treatment prevents thermal expansion during inspection, maintaining precise alignment between probes and electrode pads throughout the measurement process

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The conventional method of gradually heating the target object during inspection is replaced by rapidly preheating the probe card before contact. This rushes through the thermal equilibrium process in advance, eliminating gradual thermal expansion that would cause alignment drift during measurement

Inventive Principle:

Principle #21Skipping (Rushing through)

3Productivity

If the probes are brought into contact with the target object without preheating the probe card, then the inspection can start immediately, but the probes experience thermal expansion causing misalignment and potential damage

Engineering Contradiction:

Improveinspection throughputVSAvoidprobe and target object integrity

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The probe card is preheated to the inspection temperature before the target object is brought into contact with the probes. This preliminary thermal treatment prevents thermal expansion during inspection, maintaining precise alignment between probes and electrode pads throughout the measurement process

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The conventional method of gradually heating the target object during inspection is replaced by rapidly preheating the probe card before contact. This rushes through the thermal equilibrium process in advance, eliminating gradual thermal expansion that would cause alignment drift during measurement

Inventive Principle:

Principle #21Skipping (Rushing through)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This method enhances operating efficiency and reliability by preventing misalignment and damage, allowing for precise electrical characteristic inspections without preheating or cooling the probe card, thus improving the overall inspection process.

Implementation Method 1

the probes are heated by the target object and thus are extended by thermal expansion. Further, a main body of probe card is gradually heated by the heat transferred from the target object

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

the probes are heated by the target object and thus are extended by thermal expansion. Further, a main body of probe card is gradually heated by the heat transferred from the target object to be thermally expanded

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentUS7702475B2Method for inspecting electrical characteristics of chips and a storage medium for storing a program of the method

Publication Date: 2010.04.20 TOKYO ELECTRON LTD

AI summary

An inspecting method includes registering a pre-obtained relationship between contact time of probes with a target object having a predetermined temperature and tip positions of the probes which vary in accordance with the contact time. The method further includes inspecting one or more chips at a time by estimating the tip positions of the probes based on the relationship and the contact time of the probes with the one or more chips and then correcting the tip positions of the probes from previous tip positions based on the estimated tip positions until the probes are stable without being extended or contracted.