Co-designer and developer of a crystal growing furnace, Lorenzini joined Rheem Semiconductor in 1960, the first spin-off from Fairchild Semiconductor, where he was involved in the design and development of that furnace. After two years at Rheem, he worked for brief periods at Allegheny Electronic Chemicals in Pennsylvania and Knapic Electrophysics in Palo Alto, California. When Knapic closed down shortly after he joined, Lorenzini bought the assets and launched his own company, Elmat, to grow crystals for silicon wafer manufacturing.
Elmat was acquired by General Instruments in 1968, and he established his second startup, Siltec, in 1969. Siltec, a provider of silicon wafers and wafer making equipment, launched its IPO in 1980, and by 1984 the company had grown to $50 million in revenues. He has served as President and CEO of Siltec from its inception until 1985, when he became Chairman. In 1986 Siltec was acquired by Mitsubishi.
In 1988 Lorenzini co-founded a third company, SunPower, with Professor Richard Swanson, producing silicon PV cells and panels for generating solar power. He graduated from Stanford University in 1958 with a Bachelor's degree in Materials Science, and subsequently earned a Master's degree in 1960, also from Stanford. Lorenzini received the SEMI Award for his pioneering work in silicon crystal growth in 1979.
