Methods for manufacturing a display device

Abstract

wherein A(T) is the coefficient of thermal expansion of the transfer head, E(T) is the coefficient of thermal expansion of the substrate, T1 is room temperature, T2 is the temperature of the transfer head, and T3 is the temperature of the substrate.

What is claimed is: 
     
         1 . A method for manufacturing a display device, comprising:
 providing a plurality of light-emitting units;   providing a substrate;   transferring the plurality of light-emitting units to a transfer head; and   attaching at least one of the plurality of light-emitting units on the transfer head to the substrate by a bonding process;   wherein the transfer head and the substrate satisfy the following equation during the bonding process:
   0≤|∫ T1   T2   A ( T ) dT−∫   T1   T3   E ( T ) dT |<0.01,
 
   wherein A(T) is a coefficient of thermal expansion of the transfer head,   E(T) is a coefficient of thermal expansion of the substrate,   T1 is room temperature,   T2 is a temperature of the transfer head, and   T3 is a temperature of the substrate.   
     
     
         2 . The method as claimed in  claim 1 , wherein the transfer head and the substrate satisfy the following equation during the bonding process:
   0≤|∫ T1   T2   A ( T ) dT−∫   T1   T3   E ( T ) dT|< 0.005.
   
     
     
         3 . The method as claimed in  claim 1 , wherein a material of the transfer head is different from a material of the substrate. 
     
     
         4 . A method for manufacturing a display device, comprising:
 providing a plurality of light-emitting units;   providing a first substrate;   forming an adhesive layer on a transfer head;   attaching the plurality of light-emitting units to the adhesive layer; and   attaching at least one of the light-emitting units to the first substrate.   
     
     
         5 . The method as claimed in  claim 4 , wherein at least a portion of the adhesive layer is arch-shaped. 
     
     
         6 . The method as claimed in  claim 4 , wherein forming the adhesive layer comprises:
 forming a spacer layer on the transfer head, wherein the spacer layer comprises a plurality of openings; and   filling an adhesive material into the plurality of openings to form the adhesive layer, and the adhesive layer comprising a plurality of adhesive patterns.   
     
     
         7 . The method as claimed in  claim 6 , wherein a height of the spacer layer is less than a height of the adhesive pattern. 
     
     
         8 . The method as claimed in  claim 6 , wherein a height of the spacer layer is greater than the height of the adhesive pattern. 
     
     
         9 . The method as claimed in  claim 4 , wherein the adhesive layer comprises a bottom layer and a plurality of protruding portions, and the plurality of protruding portions are disposed on the bottom layer. 
     
     
         10 . The method as claimed in  claim 9 , wherein forming the adhesive layer on the transfer head comprises:
 providing a second substrate, wherein the second substrate includes a plurality of recesses;   coating an adhesive material on the second substrate to form the bottom layer and the protruding portions;   attaching the bottom layer to the first substrate; and   removing the second substrate.   
     
     
         11 . The method as claimed in  claim 9 , wherein attaching the plurality of light-emitting units to the adhesive layer comprises:
 attaching the plurality of light-emitting units to the plurality of protruding portions of the adhesive layer.   
     
     
         12 . The method as claimed in  claim 4 , wherein the adhesive layer comprises silicon. 
     
     
         13 . A method for manufacturing a display device, comprising:
 providing a plurality of light-emitting units;   providing a substrate;   transferring the plurality of light-emitting units to a transfer head; and   applying a laser-light to at least one of the light-emitting units so that the at least one of the light-emitting units projected by the laser-light on the transfer head is attached to the substrate.   
     
     
         14 . The method as claimed in  claim 13 , wherein the transfer head further comprises a plurality of lenses, and the laser-light is projected onto the at least one of the light-emitting units through at least one of the lenses. 
     
     
         15 . The method as claimed in  claim 13 , further comprising:
 forming a plurality of bonding pads on the substrate;   forming a capping layer to cover the bonding pad;   attaching the at least one of the light-emitting units to the bonding pads; and   curing the capping layer.   
     
     
         16 . The method as claimed in  claim 13 , further comprising heating a first portion of the substrate, and the first portion corresponds to the at least one of the light-emitting units attached to the substrate. 
     
     
         17 . The method as claimed in  claim 16 , wherein the substrate further comprises a second portion adjacent to the first portion, and a temperature difference between the first portion and the second portion is in a range from 50° C. to 350° C. when heating the first portion of the substrate. 
     
     
         18 . The method as claimed in  claim 17 , further comprising:
 providing a heat plate, wherein the heat plate includes a thermal conductive part and a thermal isolation part adjacent to the thermal conductive part; and   disposing the substrate on the heat plate so the first portion of the substrate is on the thermal conductive part and the second portion is on the thermal isolation part.   
     
     
         19 . The method as claimed in  claim 18 , wherein a width of the thermal isolation part is less than a pitch of the light-emitting units. 
     
     
         20 . The method as claimed in  claim 18 , wherein the heat plate comprises a buffer layer on the thermal isolation part.