CN-121995293-A - MEMS probe performance test method and system

CN121995293ACN 121995293 ACN121995293 ACN 121995293ACN-121995293-A

Abstract

The invention provides a method and a system for testing performance of an MEMS probe. The method comprises the steps of stroke-pressure relation test, current-carrying-pressure change test, step-increasing current-carrying-power-off test and power-carrying-on time pressure data acquisition, wherein the stroke-pressure relation test is used for calibrating an initial contact zero point, controlling a pressure sensor probe to press down a probe tip in a fixed step length, collecting needle pressure data under different strokes, generating a curve, judging the mechanical property of the probe according to the curve slope of a specific interval, and determining the current-carrying property parameter of the probe by carrying out power-on-power-off test on the probe circulation with step-increasing current after the initial needle pressure is recorded under the fixed stroke until the needle pressure change rate exceeds a threshold value. The system comprises a control and processing module, a three-dimensional motion platform, a pressure sensing module, a current source module, a visual positioning module and a data recording and displaying module. The invention realizes the integrated quantitative evaluation of the mechanical and electrical properties of the MEMS probe.

Inventors

ZHANG JIYANG
JIANG WENDE
Lou Zhaoyi

Assignees

上海道格特科技有限公司

Dates

Publication Date: 20260508
Application Date: 20260120

Claims (8)

1. The MEMS probe performance testing method is characterized by comprising the following steps of: Calibrating an initial contact zero point of a tip of an MEMS probe to be tested and a pressure sensor probe, starting from the initial contact zero point, controlling the pressure sensor probe to downwards press towards the tip direction in a fixed step length, and collecting acupressure data corresponding to different downwards pressing stroke points; The current-carrying and pressure-changing testing step comprises the steps of pressing down the pressure sensor probe to a preset fixed stroke of the probe tip, collecting initial acupressure data when the probe is not electrified, electrifying the probe for a first preset time period with a set initial current value, collecting a plurality of electrified acupressure data at fixed time intervals during electrifying, stopping electrifying and lifting the pressure sensor probe to rest the probe for a second preset time period, pressing down the probe to the fixed stroke again, repeating electrifying, data collecting and resting processes after increasing the current value, circularly executing the steps until the calculated change rate of the electrified acupressure data relative to the initial acupressure data exceeds a preset threshold value, and determining current-carrying performance parameters of the probe according to the recorded current value and the corresponding acupressure data.
2. The method of claim 1, wherein determining the mechanical properties of the probe based on the slope of the pressure change over the set travel range comprises calculating the slope of the travel-pressure relationship curve over the travel range from 60 μm to 80 μm, and determining that the mechanical properties of the probe are acceptable if the slope is less than 0.02.
3. The method according to claim 1, wherein the pressure sensor probe is controlled to be pressed downwards towards the needle tip in a fixed step length, specifically, from the initial contact zero point, the probe is controlled to be pressed downwards to 100 μm of the total stroke in 10 steps in a step length of 10 μm, and the corresponding acupressure value is recorded after each step of pressing downwards is stabilized.
4. The method of claim 1, wherein the predetermined threshold is 20% and the rate of change is calculated as I initial acupressure-energized acupressure I/initial acupressure.
5. The method according to claim 1, wherein the increasing current value is in particular 100mA per cycle, the first predetermined time period is 120 seconds, the fixed time interval is 30 seconds, and the second predetermined time period is 30 seconds.
6. A MEMS probe performance test system, comprising: the control and processing module is used for executing test flow control, data acquisition instruction issuing and data processing analysis; the three-dimensional motion platform is connected with the control and processing module and comprises an XY plane motion module for loading the MEMS probe to be tested and a Z-axis motion module for driving the pressure sensing module; the pressure sensing module is arranged on the Z-axis motion module of the three-dimensional motion platform, and the probe is used for applying downward pressure to the tip of the MEMS probe to be tested and measuring the needle pressure in real time; The current source module is connected with the control and processing module and used for providing programmable step current for the MEMS probe to be tested according to a test instruction; the visual positioning module is used for acquiring the image of the MEMS probe tip to be detected and guiding the three-dimensional motion platform to finish positioning; And the data recording and displaying module is used for storing the test data and displaying the test curve and the result.
7. The system of claim 6, further comprising a test fixture mounted on the XY plane motion module of the three-dimensional motion platform for fixedly loading the MEMS probe to be tested, wherein the test fixture comprises a test PCB provided with a gold-plated area electrically contacted with the probe tail and a connection terminal electrically connected with the gold-plated area, and the connection terminal is connected with the current source module to form a current loop.
8. The system of claim 6, wherein a data analysis template is preset in the control and processing module for automatically generating a stroke-pressure relationship curve and a current-pressure change curve according to the data collected by the pressure sensing module.

Description

MEMS probe performance test method and system Technical Field The invention relates to the technical field of semiconductor testing, in particular to a method for testing the comprehensive mechanical and electrical properties of a micro-electromechanical system (MEMS) probe and a testing system for realizing the method. Background MEMS probes are critical to the stability of their performance as key interface components in wafer testing (CP testing). At 60-80 μm hold-down, the ideal probe should provide a stable and consistent contact pressure (acupressure) over a set range of working strokes (Overdrive, OD) while maintaining a stable pressure when carrying a specific test current to ensure good electrical contact and reduce damage to the device under test. Currently, the evaluation of the MEMS probe in the industry focuses on single performance such as simple conduction test or static pressure measurement, and lacks a method capable of systematically simulating actual test conditions and quantitatively analyzing the comprehensive performance of the probe in dynamic pressing and electrifying heating states. The probe model selection is often dependent on experience, and risks such as poor test repeatability, yield fluctuation and even chip damage caused by inconsistent probe force or insufficient current carrying capacity are easily introduced. Therefore, developing a set of method and system capable of comprehensively and accurately evaluating the stroke-pressure characteristic and the current-carrying-pressure variation characteristic of the MEMS probe has urgent demands and great significance for improving the reliability, consistency and efficiency of semiconductor testing. Disclosure of Invention The invention provides a method and a system for testing the performance of an MEMS probe, which are used for solving the problems that the performance evaluation of the MEMS probe is incomplete and is not systematic and the comprehensive performance of the MEMS probe in a simulated real working state cannot be quantified in the prior art. The method aims to accurately measure the change rule of the probe needle pressure along with the pressing stroke and evaluate the pressure stability of the probe needle pressure under the step increasing current load, thereby providing objective and quantized data basis for scientific selection, adaptation verification, quality control and performance degradation analysis of the probe. In order to achieve the above purpose, the invention adopts the following technical scheme: in a first aspect, the present invention provides a method for testing performance of a MEMS probe, the method integrating a stroke-pressure relationship test and a current-carrying-pressure variation test, specifically comprising the steps of: s1 test of stroke-pressure relation S11, preparing and positioning. And installing the MEMS probe to be tested on a special test jig, and fixing the jig on a motion platform of a test system. And identifying the position of the probe tip through a vision system, and controlling the motion platform to move the probe tip to the position right below the pressure sensor probe. S12, zero point calibration. And controlling the pressure sensor probe to slowly move downwards (negative Z axis), and recording the current position as a contact point when the pressure reading first appears a stable value larger than zero. And continuing fine tuning until the pressure value is just zeroed and the probe is kept electrically conductive with the conductive pad on the test fixture, and accurately defining the position as a mechanical zero point (0 OD point). S13, step depression and data acquisition. From the 0OD point, the pressure sensor probe is controlled to be pressed down toward the probe tip in a fixed step size (e.g., 10 μm). After each step is pressed down and stabilized, the current accumulated pressing stroke (OD value) and the corresponding real-time acupressure value are recorded. This process is repeated and pressure data is collected at a series of predetermined travel points (e.g., from 10 μm to 100 μm). And S14, curve generation. The acquired (down stroke, acupressure) data pair is processed, and a stroke-pressure relation curve of the probe is automatically generated. And S15, performance judgment. Based on the generated stroke-pressure relationship curve, the slope of the curve over a preset critical stroke interval (e.g., 60 μm to 80 μm) is calculated. If the slope value is smaller than the set qualification threshold (such as 0.02), the mechanical property of the probe is judged to be qualified, which indicates that the pressure change in the working interval is gentle and the consistency is good. S2 Current carrying-pressure Change test S21, initial state setting. The pressure sensor probe is controlled to be depressed to a preset fixed stroke (e.g., od=100 μm). In this state, a stable acupressure value at the time of no current flow is recorded as an initi