Epitaxial lift off systems and methods
View Patent ↗Epitaxial lift off systems and methods are presented. In one embodiment a tape is disposed on the opposite side of the epitaxial material than the substrate is used to hold the epitaxial material during the etching and removal steps of the ELO process. In various embodiments, the apparatus for removing the ELO film from the substrates without damaging the ELO film may include an etchant reservoir, substrate handling and tape handling mechanisms, including mechanisms to manipulate (e.g., cause tension, peel, widen the etch gap, etc.) the lift off component during the lift off process.
1. A method for performing etching to separate an epitaxial lift off component from a support substrate using a belt and chain apparatus, the method comprising:
using an etchant application component that comprises a substrate pocket and an etchant supply component, wherein the etchant supply component includes a plurality of etching spray nozzles;
coupling the epitaxial lift off component to a tape using a tape application component, wherein a sacrificial layer is between the epitaxial lift off component and the substrate;
directing an etchant spray towards the tape and the substrate;
routing an etchant to the sacrificial layer using an etchant delivery system; and
separating the epitaxial lift off component from the substrate using a separation assistance component, wherein the separation assistance component comprises a drive link ramp, a chain drive, guide rails, and pin rails.
2. The method of claim 1 , wherein the drive link ramp comprises an elongated slot and a height that increases from a first end of the apparatus through an etching section.
3. The method of claim 1 , wherein the chain drive comprises a plurality of drive pins.
4. The method of claim 1 , wherein the separation assistance component further comprises a plurality of point loads configured to contact the center of the tape as the tape is driven along and up an increasing height of the drive link ramp.
5. The method of claim 1 , wherein each guide rail includes a guide slot that receives one side of the tape and a plurality of index pin receiving holes.
6. The method of claim 5 , wherein each pin rail includes a plurality of index pins.
7. The method of claim 6 , wherein the pin rails are operable to be lowered with respect to the guide rails such that the plurality of index pins extend into the plurality of index pin receiving holes and through a plurality of engagement slots along sides of the tape.
8. The method of claim 6 , wherein the separation assistance component further comprises two pin rails.
9. A method for performing etching to separate an epitaxial lift off component from a support substrate using a belt and chain apparatus, wherein the belt and chain apparatus comprises:
an etchant application component that comprises a substrate pocket and an etchant supply component, wherein the etchant supply component includes a plurality of etching spray nozzles;
a tape application component configured to couple the epitaxial lift off component to a tape, wherein a sacrificial layer is between the epitaxial lift off component and the substrate;
an etchant spray configured to be directed towards the tape and the substrate;
an etchant delivery system configured to route an etchant to the sacrificial layer; and
a separation assistance component configured to separate the epitaxial lift off component from the substrate, wherein the separation assistance component comprises a drive link ramp, a chain drive, guide rails, and pin rails.
10. The method of claim 9 , wherein the drive link ramp comprises an elongated slot and a height that increases from a first end of the apparatus through an etching section.
11. The method of claim 9 , wherein the separation assistance component further comprises a plurality of point loads configured to contact the center of the tape as the tape is driven along and up an increasing height of the drive link ramp, and wherein each pin rail includes a plurality of index pins.
12. The method of claim 11 , wherein each guide rail includes a guide slot that receives one side of the tape and a plurality of index pin receiving holes.
13. The method of claim 12 , wherein the pin rails are operable to be lowered with respect to the guide rails such that the plurality of index pins extend into the plurality of index pin receiving holes and through a plurality of engagement slots along sides of the tape.
14. The method of claim 13 , wherein the separation assistance component further comprises two pin rails.