Semiconductor device

Abstract

Abstract PURPOSE:To obtain a high voltage generating circuit capable of corresponding to the thickness of a film of oxide film by inspecting whether a stable writing is obtained or not after a voltage Vpp is impressed and by automatically raising Vref by one step when the inspected result is NO. CONSTITUTION:When a clock 1(30) goes to H level, a raised Vpp is impressed correspondingly to a raised Vref 33 and at the same time, a capacitor C1 is charged again by a power source voltage. When it is judged to be unsatisfactory as a result of this writing inspection, further, a clock 2(31) is outputted and an electric charge of the capacitor C1 and a capacitor C2 is distributed to a parallel circuit of the capacitor C1 and the capacitor C2. As a result of this, a voltage of a node point N2 is raised further, a peak value (h) of the Vpp is also raised and a writing is performed again. When it is judged that the writing is fully performed, a reset pulse 32 is outputted in place of the clock 2(31) and the voltage of the node point N2 goes to a voltage Vs. Thereby, even if the thickness of the film of oxide film is not uniform, an effective writing can be constantly performed and a reliability is improved.

Inventors

• 👤 Yasushi Terada
• 👤 寺田　康
• 👤 Takeshi Nakayama
• 👤 武志 中山
• 👤 Kazuo Kobayashi
• 👤 和男 小林

Bibliographic Details