Henry F. Gray, 62, a Naval Research Laboratory physicist and senior research scientist who was a pioneer in the field of vacuum microelectronics technology, died of cancer July 21 at the Hospice of Northern Virginia.

Vacuum microelectronics is a relatively recent development that combines some of the features of the old vacuum tubes with the advances of modern solid-state microelectronics, and Dr. Gray has been credited with helping to give the field its name.

In the mid-1980s, Dr. Gray and his associates at the Naval Research Laboratory developed a vacuum microelectronics transistor that has been considered for application in ultrathin high-definition television screens as well as in certain types of advanced computers.

Dr. Gray was engaged in research on other business applications of the technology such as super-high-frequency cellular telephone systems. He stopped working in December 1998, but sporadically returned to his office until his health began to fail in recent months.

In his work, Dr. Gray etched tiny vacuum components on a silicon chip to help create devices that he said could be, in certain circumstances, faster and more reliable than those relying solely on solid-state technology. The microtubes have the capability of high-speed operation, Dr. Gray said, because in the vacuum there is less resistance to the motion of electrons than within solid-state devices.

In an interview with The Washington Post in 1989, Dr. Gray said vacuum microelectronic devices could be of particular use in extreme or battlefield environments, where equipment could be subjected to enormous temperatures or intense radiation.

Dr. Gray was a native of Montclair, N.J. He received bachelor's and doctoral degrees in physics from the University of Notre Dame. He served in the Navy from 1959 to 1962.

He joined the Naval Research Laboratory in 1967 as an experimental surface physicist in the electronics science and technology division.

He was a member of Good Shepherd Catholic Church in Alexandria and the International Vacuum Microelectronics Conference.

Survivors include his wife, Joan G. Gray of Alexandria; three children, James R. Gray of New York City, Elizabeth Marie Gray of Volcano, Hawaii, and Catherine Ann Gray of Seattle; two brothers; and a sister.