Test Apparatus For Flip-Chip Micro-Light Emitting Diode (LED) Devices

1 . A test apparatus for an array of micro-light emitting diode (uLEDs), the test device comprising:

a primary release layer positioned on the array of uLEDs;

an N-contact test pad template in contact with N-contacts of the uLEDs and an N-contact testing bus; and

a P-contact test pad template in contact with P-contacts of the uLEDs and a P-contact testing bus.

2 . The test apparatus of claim 1 , wherein the N-contacts of the uLEDs are connected in parallel with the N-contact testing bus and/or the P-contacts of the uLEDs are connected in parallel with the P-contact testing bus.

3 . The test apparatus of claim 1 , wherein the primary release layer comprises a photoresist material.

4 . The test apparatus of claim 3 , wherein the photoresist material comprises polydimethylglutarimide (PMGI) and/or a cyclopentanone-based polymer.

5 . The test apparatus of claim 1 , wherein the uLED array comprises a device substrate comprising a material selected from the group consisting of: a sapphire, silicon carbide, and III-nitride.

6 . The test apparatus of claim 1 further comprising an array support.

7 . The test apparatus of claim 1 , wherein each of the N-contact test pad template and the P-contact test pad template comprises one or more of: copper (Cu), aluminum (Al), nickel (Ni), titanium (Ti), titanium-tungsten (TiW), silver (Ag), gold (Au), platinum (Pt), and palladium (Pd).

8 . The test apparatus of claim 1 effective for testing greater than or equal to 10,000 uLEDs at a time.

9 . The test apparatus of claim 8 effective for testing greater than or equal to 100,000 uLEDs at a time.

10 . The test apparatus of claim 9 effective for testing greater than or equal to 500,000 uLEDs at a time.

11 . A method of manufacturing a light source comprises:

testing an array of micro-light emitting diode (uLEDs) with the test apparatus according to claim 1 ; and

assembling a light source comprising uLEDs identified as acceptable upon the testing.

12 . The method of claim 11 , wherein the testing comprises:

applying power to the test apparatus;

detecting light emission from the test apparatus with an optical sensor; and

identifying acceptable and/or defective pixels.

13 . The method of claim 11 further comprising generating a pixel map of locations of the acceptable and/or defective pixels.

14 . The method of claim 13 further comprising conducting a pick-and-place operation including only uLEDs comprising the acceptable pixels.

15 . A method of manufacturing a test apparatus for testing an array of micro-light emitting diode (uLEDs), the method comprising:

depositing a primary release material on the array of uLEDs, each uLED comprising: a pixel, an N-contact, and a P-contact, each of the N-contact and the P-contact in contact with each of the pixels;

etching the primary release material to expose each of the N-contacts and the P-contacts, thereby forming a primary release layer; and

preparing an N-contact test pad template on each of the N-contacts, an N-contact testing bus in communication with the N-contact test pad template, a P-contact test pad template on each of the P-contacts, and a P-contact testing bus in communication with the P-contact test pad template.

16 . The method of claim 15 , wherein preparing the N-contact test pad template, the N-contact testing bus, the P-contact test pad template, and the P-contact testing bus comprises: depositing a test pad material on the array; and patterning the test pad material.

17 . The method of claim 15 , wherein preparing the N-contact test pad template, the N-contact testing bus, the P-contact test pad template, and the P-contact testing bus comprises: depositing a mask material in a pattern on the array, depositing a test pad material, and removing the mask material.

18 . The method of claim 15 , wherein the N-contacts of the uLEDs are connected in parallel with the N-contact testing bus, and/or the P-contacts of the uLEDs are connected in parallel with the P-contact testing bus.

19 . The method of claim 15 , wherein the primary release layer comprises a photoresist material.

20 . The method of claim 15 , wherein the N-contact test pad template, the N-contact testing bus, the P-contact test pad template, and the P-contact testing bus comprises one or more of: copper (Cu), aluminum (Al), nickel (Ni), titanium (Ti), titanium-tungsten (TiW), silver (Ag), gold (Au), platinum (Pt), and palladium (Pd).