The interactions of photons below about 800 nm provide thermal effects and quantum photo-effects. The performance of rapid thermal processing (RTP) techniques can be improved manifold by exploiting the use of quantum photo-effects in thermal processing. Photo excitations of species taking part in a chemical reaction or solid-state phenomena (e.g. annealing, solid-phase epitaxy etc.) lead to reduced activation energy. The quantum photo-effects dominated RTP is called rapid photothermal processing (RPP). At lower processing temperatures (compared to RTP), semiconductor devices with batter performance, reliability and yields can be processed by RPP. Manufacturing of silicon integrated circuits (ICs) with dimension as low as 20 nm feature sizes is expected to dominate the 21st century. The ultra small feature size coupled with 12 in. (may be even 18 in.) diameter wafers will force the IC manufacturers to reduce the processing temperature to the point that only RPP can provide the desired performance, reliability and yields. This new era of low processing temperature of silicon IC processing will provide new capabilities in the processing of compound semiconductors related electronic and optical devices. The low-processing temperature aspect of RPP coupled with high throughput also opens new doors for large area devices such as solar cells and flat panel displays. The major challenge is the development of commercial equipment for manufacturing of ICs, solar cells and flat panel etc.