He developed the planar process, an important technology for reliably fabricating and manufacturing semiconductor devices, such as transistors and integrated circuits.
[3] In 1952, he moved to the United States to work at the California Institute of Technology, where he became acquainted with William Shockley, a physicist at Bell Labs who was intimately involved with the creation of the transistor.
Later, Hoerni attended a meeting where Atalla presented a paper about passivation based on the previous results at Bell Labs.
The planar process provided a powerful way of implementing an integrated circuit that was superior to earlier conceptions of the device.
He contributed the lion's share, $30,000, to Greg Mortenson's project to build a school in the remote village of Korphe, and later founded the Central Asia Institute with an endowment of $1 million to continue providing services for them after his death.
[17][18] Hoerni named Greg Mortenson as the first Executive Director of the organization, which continues to build schools in Pakistan and Afghanistan.
The author claimed that Jay Last pointed out that Hoerni had incredible stamina and could hike for hours on little food or water.