Self-aligned masking for solar cell manufacture

A method of performing a patterned implant in a crystalline substrate, comprising:

• performing a first patterned implant configured to create an amorphous portion of said substrate, wherein a crystalline portion of said substrate remains;
• applying a photoresist to a surface of said substrate;
• applying light in a predetermined frequency range to said surface at a predetermined intensity level, whereby said intensity level is insufficient to set said photoresist;
• using the reflectivity of said substrate to augment said applied light, wherein an amount of light reflected by said amorphous portion is greater than an amount of light reflected by said crystalline portion, wherein the amount of light reflected by one of said portions, when added to said applied light is capable of setting said photoresist, and wherein the amount of light reflected by the other of said portions, when added to said applied light is incapable of setting said photoresist;
• removing photoresist which was not set;
• and
• exposing said substrate to a second implant, wherein said photoresist masks one of said amorphous portion or said crystalline portion from said second implant.

A method of performing a patterned implant in a crystalline substrate, comprising:

• performing a first patterned implant configured to create an amorphous portion of said substrate, wherein a crystalline portion of said substrate remains;
• applying a thermal polymer to a surface of said substrate;
• applying light in a predetermined frequency range to said substrate at a predetermined intensity level to heat said substrate;
• using the energy absorption of said substrate to heat said polymer, wherein said energy absorption of said amorphous portion is greater than said energy absorption of said crystalline portion such that said amorphous region is sufficiently heated to set said thermal polymer and said energy absorption of said crystalline portion is insufficient to set said thermal polymer;
• removing said thermal polymer which was not set;
• and
• exposing said substrate to a second implant, wherein said thermal polymer masks said amorphous portion from said second implant.