Memory circuit, dynamic random access memory and operation method thereof
The present disclosure provides a dynamic random access memory, which includes a storage diode and a control-FET. The storage diode is composed of a gate-floating FET, and two source/drains of the gate-floating FET serve as a cathode and an anode of the storage diode. The control FET is electrically connected to the cathode or the anode of the storage diode.
1. A dynamic random access memory, comprising:
a storage diode consisting of a gate-floating FET (field-effect transistor), wherein two source/drains of the gate-floating FET serve as a cathode and an anode of the storage diode, wherein the storage diode comprises:
a first gate; and
a first source/drain region and a second source/drain region disposed at opposite sides of the first gate, wherein the second source/drain region is electrically connected to a source line, and the first gate is floated; and
a control FET electrically connected to the cathode or the anode of the storage diode.
2. The dynamic random access memory of claim 1 , wherein the control FET comprises:
a second gate; and
a second source/drain region and a third source/drain region disposed at opposite sides of the second gate.
3. The dynamic random access memory of claim 2 , wherein the control FET further comprises:
a first channel region disposed between the second source/drain region and the third source/drain region; and
a first dielectric layer region disposed between the second gate and the first channel region.
4. The dynamic random access memory of claim 3 , wherein the control FET and the storage diode share the second source/drain region.
5. The dynamic random access memory of claim 1 , wherein the storage diode further comprises:
a second channel region disposed between the first source/drain region and the second source/drain region; and
a second dielectric layer region disposed between the first gate and the second channel region.
6. The dynamic random access memory of claim 2 , wherein the second source/drain region is electrically connected to a bit line, and the second gate is electrically connected to a word line.
7. A memory circuit, comprising:
a plurality of memory units arranged in an array, each of the memory units comprising a dynamic random access memory, and the dynamic random access memory comprising:
a control FET having a gate electrically connected to a word line; and
a storage diode consisting of a gate-floating FET, wherein two opposite ends of the storage diode are electrically connected to a source line and one end of the control FET respectively, and another end of the control FET is electrically connected to a bit line.
8. The memory circuit of claim 7 , wherein each of the memory units further comprises another dynamic random access memory, and the another dynamic random access memory comprises:
another control FET having a gate electrically connected to another word line; and
another storage diode consisting of another gate-floating FET, wherein two opposite ends of the another storage diode are electrically connected to another source line and one end of the another control FET respectively, and another end of the another control FET is electrically connected to the bit line.
9. An operation method of a dynamic random access memory, the dynamic random access memory comprising a storage diode and a control FET connected in series, and the storage diode consisting of a gate-floating FET, and the operation method comprising steps of:
when writing the dynamic random access memory, applying a control voltage to a word line, applying a writing voltage to a bit line, and applying a zero voltage to a source line, wherein a gate of the control FET is electrically connected to the word line, two opposite ends of the storage diode are electrically connected to the source line and one end of the control FET respectively, and another end of the control FET is electrically connected to the bit line.
10. The operation method of claim 9 , wherein the control voltage turns on the control FET, and the writing voltage causes the storage diode to generate a Zener tunneling mechanism, so that the storage diode stores charge.
11. The operation method of claim 9 , further comprising:
when refreshing the dynamic random access memory, applying the control voltage to the word line, applying the writing voltage to the bit line, and applying the zero voltage to the source line.
12. The operation method of claim 9 , further comprising:
when reading the dynamic random access memory, applying the control voltage to the word line, applying a read voltage to the source line, and sensing a read current through the bit line.
13. The operation method of claim 12 , wherein a polarity of the read voltage is opposite to a polarity of the writing voltage.