Ramped, variable power UV adhesive cure process for improved alignment
View Patent ↗Methods and apparatuses for adhering optoelectronic components in optical, electronic or optoelectronic devices are disclosed. A UV-active adhesive is applied to an alignment sensitive component of the device. A first, relatively low dose of UV radiation sufficient to solidify an outer layer of the adhesive is applied to the adhesive. A second, relatively high dose of UV radiation sufficient to solidify the remaining thickness of the adhesive is then applied. The methods and apparatuses of the present invention advantageously reduce or eliminate changes in the position of a component during the adhesive curing process. The present method and apparatus allow for shorter total time for solidifying the adhesive, provide stable positioning during the adhesive solidification process, and enable increased manufacturing output and decreased waste.
1. A method of adhering components in an optical, electronic, or optoelectronic device, comprising:
a) applying a UV-active adhesive onto an alignment-sensitive component of the device;
b) placing the alignment-sensitive component into the device, the device being attached to an adjustable base;
c) applying a first, relatively low dose of UV radiation to the adhesive sufficient to solidify an outer layer of the adhesive; and
d) applying a second, relatively high dose of UV radiation to the adhesive sufficient to solidify a remaining thickness of the adhesive.
2. The method of claim 1 , wherein applying each of the first dose of UV radiation and the second dose of UV radiation comprises providing sufficient current or power to at least one LED to cause the at least one LED to emit UV light at the relatively low and the relatively high doses, respectively.
3. The method of claim 2 , wherein the first current is from about 10 to 100 mA, the second current is from about 25 to 200 mA, and the second current is higher than the first current.
4. The method of claim 1 , wherein the first dose of UV radiation is applied for about 1 second to about 15 seconds.
5. The method of claim 4 , wherein the second dose of UV radiation is applied for about 1 second to about 15 seconds.
6. The method of claim 1 , further comprising, after placing the alignment-sensitive component into the device and before applying the first dose of radiation, adjusting a position of the device while monitoring an output parameter of the alignment-sensitive component.
7. The method of claim 6 , further comprising determining a maximum value of the output parameter, and applying the first dose of UV radiation when the output parameter is at the maximum value.
8. The method of claim 1 , wherein the first dose and the second dose are applied for a total of from 3 to 25 seconds.
9. The method of claim 1 , wherein the alignment-sensitive component comprises a photodiode.
10. The method of claim 1 , further comprising placing the alignment-sensitive component into a metal housing.
11. The method of claim 1 , wherein the adhesive comprises a UV-active epoxy.
12. The method of claim 1 , wherein the first dose has a minimum intensity of about 50 mW/cm 2 .
13. The method of claim 1 , wherein the device is an optoelectronic transceiver.