Semi-Automatic Pixel Prober

Model 780-Px

 

  

Introduction.

  As demand for larger Flat Panel Display increases, in conjunction with desire to improve yield and manufacturing efficiency, Manufacturers of Flat Panel Display (TFT) are making larger glasses with 4, 6 or even 9 displays on a Mother Glass. In this ‘large glass’ scenario, either for device characteristic, leakage or uniformity, Manufacturers need to probe and test any individual pixel on the large glass. The TNP’s Pixel Prober was designed in response to this new industry’s demands.  

System Description

  System ported large, double platforms frame (see Fig. 1):

q       Lower platform has a large X-Y Stage to accommodate large glass (up to 1x1.2 meter for 5th gen.). The stage is controlled by a Joystick Controller (computer control is optional). Operator uses this joystick (or computer) to index the specific panel on the large glass into operating area of the upper level. A Theta Control allows Operator to adjust for perfect alignment. This stage is referred to as “Lower Stage”.

q       Upper platform comprises of 4 cameras, 3 monitors and 3 programmable –with built-in edge sensors- probes. They are designed to cover the entire area of a display panel on the large glass below.  

o       P1: Probe #1, probes across the Data lines of the display panel on the X-Axis.

o       C1: Lipstick Camera #1, attached to P1, looking at P1 probing area. Camera Focus controlled by Computer. Also served as ‘right alignment’ camera.

o       M1: monitor #1 showing image from C1. Same image could also be selected and displayed on computer monitor.

o       P2: Probe #2, probes along the Gate lines of the display panel on the Y-Axis.

o       C2: Lipstick Camera #2, attached to P2, looking at P2 probing area. Camera Focus controlled by Computer.

o       M2: monitor #2 showing image from C2. Same image could also be selected and displayed on computer monitor.

o       PC: Center Probe, running on both X&Y-Axes, probes inside any pixel of the display panel.

o       CC: Center Lipstick Camera, attached to PC probing area, looking at PC probe. Camera Focus controlled by Computer.

o       MC: Center monitor, showing image from CC. Same image could also be selected and displayed on computer monitor.

o       C3: Lipstick Camera #3. Served as ‘left alignment’ camera.

o       Monitor Select Switch shows either image from C2 or C3 to be display on M2

 

Figure 1

Operations:

  Operator loads large glass with 6 display panels into the lower stage. Operator makes sure that glass is straight against alignment pins on stage. Vacuum is activated to hold panel in place.

  Operator initiates PMAGIC and specifies parameter file appropriate for the panel being tested. After initialization, PMAGIC will send C1 to extreme right position for alignment. Operator sets Monitor Select SW. to ‘Alignment’ to show image from C3 on M2. With Joystick control, operator set lower stage to have both left and right Fiducial align on M1 and M2. Using Theta Control if necessary.

 

 

 

 

 

 

                               Mother Glass with 6 display panels as used in example above

 

After Glass Alignment is achieved, operator put Monitor Select SW. back to ‘Run’. From here on, M2 will show image from C2.

Operator clicks [Continue] button on PMAGIC Windows. In response, PMAGIC will ask, “Defect Data file available? YES/NO”. If operator clicks ‘NO’, PMAGIC will default to Manual Mode.  

In Manual Mode PMAGIC would first send P1, P2 and PC to home positions. Here, operator would see Data 1, Gate 1 and Pixel (1; 1) on monitor M1, M2 and MC, accordingly(1).

PMAGIC prompts operator, step-by-step in this Mode. Example:

PMAGIC Prompt: Enter Data Line.

Operator types: 1715 [ENTER]

PMAGIC Prompt: Enter Gate Line.

Operator types: 729 [ENTER]

PMAGIC will immediately drive P1 to Data Line 1715, P2 to Gate Line 729 and PC to the pixel where the specified Gate and Data line meet(2). When Operator clicks [PROBES DOWN], PMAGIC will drive all 3 probes until they touch down on panel at their appropriate locations. PMAGIC will stop the probes, individually, after each achieves a pre-determine over-travel distance (0-255 microns). Upon finishing this task, PMAGIC will prompt [Start Test]. Operator performs required tasks to get the measurements/readings at current pixel (transistor). When finish, Operator will notify PMAGIC by clicking [Test Complete] button. PMAGIC raises all probes from panel for clearance by a pre-determined distance and prompt operator again for next test site. Operator would enter Data line = 0 and Gate Line = 0 to indicate [End of Panel].

Upon completion of each panel, PMAGIC sends all 3 probes to home position: Data 1, Gate 1 and Pixel (1; 1). Operator uses joystick to index lower stage to bring next panel into working area of the upper platform.

If Defect Data File is available, PMAGIC will read the data (via GPIB, RS-232, Floppy, Hard Disk, LAN…). PMAGIC will, then, go to any defect location as specified by operator or stepping to [Next Defect] if received such command from operator… At each defect location, PMAGIC will pause and let operator perform required measuring tasks… process repeats and continues as in Manual Mode.

Please ask your local Representative for copy of PMAGIC Instruction Manual to get more of PMAGIC features and system options, including:

• Custom software operates under Microsoft Windows 95/98 environment allowing user-friendly semi-automatic operation. Provides "point-and-shoot" on screen navigation.

• Multimedia Video Digitizing Graphics card displays live video image on the computer screen. It supports point-and-shoot, drag-and-drop, line width measuring, storage/retrieval and printing of video images.

• Reading data (panel or BATCH) from PDI’s Defect Data Files and perform “Search” function to the desired defect locations. Data format by other manufacturers also available upon request.

 After reading the X, Y coordinates, via RS-232C, from floppy disk, LAN, GPIB or operator’s keyboard entries, PMAGIC will move probes to defect location and stop, giving Operator time to perform required measuring tasks.

·   Script Language: this built-in feature to PMAGIC allows user to custom the way PMAGIC runs to suit customer's own mode of operation. It also provides the flexibility to automate and run many different panel and glass sizes. Operator accesses a specific Script file for a specific panel size and type. Number of panel setup is unlimited.

(1)  Pixel Prober is designed to address and probe all pixels and lines, without GREY or BLACKOUT area.

(2 For connections to drivers outside the panel, manufacturers usually group Gate and Data Lines in to many groups along the edges of the panel, with large and uneven gaps between groups. PMAGIC would convert the Gate and Data Line numbers into the correct lines and groups, by skipping over gaps, for proper probing of the correct Gate and Data Lines.