Floating gate isolation and method of making the same

Method for manufacturing an array of semiconductor devices on a substrate, each device having a floating gate, comprising:

• first forming isolation zones in the substrate,
• thereafter forming a floating gate separator on the isolation zones at locations where separations between adjacent floating gates are to be formed,
• after forming the floating gate separator, reducing the dimensions of the floating gate separator followed by forming the floating gates on the substrate between parts of the floating gate separator, and
• thereafter removing the floating gate separator so as to obtain slits in between neighboring floating gates.

An array of semiconductor devices with a floating-gate to control-gate coupling ratio, comprising:

• a substrate with a planar surface,
• an isolation zone in the substrate in and substantially planar with the planar surface,
• at least two floating gates extending on the substrate in a first direction, each floating gate partially overlapping the isolation zone and comprising floating gate material,
• a slit between the two floating gates, and
• a control gate extending laterally with respect to the planar surface over the floating gates,
• wherein at least one of the floating gates is provided with a sharp tip of floating gate material both in the first direction and in a second direction including an angle with the first direction.