Context: Semi-additive is the most common process: The unpatterned board has a thin layer of copper already on it. A reverse mask is then applied. (Unlike a subtractive process mask, this mask exposes those parts of the substrate that will eventually become the traces.) Additional copper is then plated onto the board in the unmasked areas; copper may be plated to any desired weight. Tin-lead or other surface platings are then applied. The mask is stripped away and a brief etching step removes the now-exposed bare original copper laminate from the board, isolating the individual traces. Some single-sided boards which have plated-through holes are made in this way. General Electric made consumer radio sets in the late 1960s using additive boards.

Question: In the semi-additive process, what do the areas exposed by the mask become at the end?
Answer: traces

Question: What metal is used to plate the unmasked parts of the board in the semi-additive method?
Answer: copper

Question: After the mask comes off of the board, what step takes off the original plating?
Answer: etching

Question: What company used to make radios with additive boards in the mid-20th century?
Answer: General Electric

Question: What weight of plating is possible with copper?
Answer: any

Question: Fully additive is the most common what?
Answer: Unanswerable

Question: Additional silver is plated onto what?
Answer: Unanswerable

Question: Who made consumer radio sets in the late 1940s using additive boards?
Answer: Unanswerable

Question: The patterned board has a thin layer of what already on it?
Answer: Unanswerable