Short circuit detection method for high precision thin film circuit of liquid crystal display panel

Abstract

The invention relates to a liquid crystal display screen high accuracy film circuit testing method which comprises the following steps: dividing the chip latch of the liquid crystal display screen high accuracy film circuit into two parts which were divided by line and row, choosing partly chip latch corresponding driving film circuit to extract to the chip center direction, using the tester to do short-circuiting check to the extracted driving film circuit.

Description

technical field [0001] The invention relates to a short-circuit detection method of a high-precision thin-film circuit of a liquid crystal display, which is a detection method invented for the short-circuit defect of a liquid crystal display thin-film circuit of a substrate chip on a glass surface. Background technique [0002] The liquid crystal display product of glass surface substrate chip refers to the liquid crystal display whose chip is fixed on the glass through anisotropic conductive glue, and the display circuit in the screen is driven by the chip. [0003] The characteristics of this kind of liquid crystal display are: 1. The liquid crystal display is driven by a chip fixed on the glass; 2. The metal thin film circuit in the display is highly dense: dozens of metal thin film circuits are etched in every millimeter of space. The narrowest metal thin film wire is only 12 microns, and the distance between metal thin film wires is usually only 15 microns. [0004] Th...

AI Technical Summary

Problems solved by technology

[0009] 2. Inconvenient ordering and long delivery time

Probes or other parts are imported from abroad, the transportation risks are high, and the arrival time is long, which brings inconvenience to production testing

[0010] 3. The liquid crystal display circuit pattern detection machine is a precision machine, which needs to be specially trained for the operating staff to use and maintain knowledge

Otherwise, the machine equipment will be damaged

[0011] 4. Limitations of in-box inspection: (1) Strict requirements on line width and spacing: LCD circuit pattern inspection machine can only be used for products with an interval of 80 microns (thin film conductor width greater than 70 microns / spacing greater than 10 microns) to test

However, for products with thin-film wire widths less than 70 microns or pitches less than 10 microns, the LCD circuit pattern detector cannot detect them.

There are also some new equipment that can detect products with a spacing (thin film conductor width + spacing) of 55 microns, but it is powerless to detect products with a spacing of less than 55 microns, and the equipment is more expensive

[0012] (2), detection is not complete: ① can not detect irregular graphics products

Only pure dot matrix products can be detected, and short circuit detection cannot be performed for segmented products

②Even if it is a dot matrix product, it cannot be fully checked

In actual production and application, this kind of detection is generally limited to detecting whether the thin-film circuit used for row driving in dot matrix products is short-circuited, but cannot detect the thin-film circuit used for column driving

[0013] (3), the probe is easy to scratch the detected graphic circuit during detection

[0019] Although the out-of-box inspection can detect the overall display effect of the product, it is impossible to determine whether the cause of the short circuit defect is the poor quality of the chip itself, the poor quality of the chip bonding, or the short circuit of the high-precision thin film circuit inside the LCD screen.

It takes a lot of time to identify the cause of failure for each non-conforming product

[0020] If the high-precision thin film circuit inside the LCD screen is short-circuited, the chip may be damaged when the chip is recovered

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