Semiconductor device and method of manufacturing the same

A method of manufacturing a semiconductor device, comprising:

• sequentially forming, on a first conductor, a first insulator, a second conductor, and a second insulator;
• forming a hole in which a top surface of the first conductor and side surfaces of the first insulator, the second conductor, and the second insulator are exposed;
• etching a portion of the second conductor from the hole;
• forming a third conductor in the etched portion of the second conductor;
• burying a sacrificial member in the hole;
• removing the second insulator and applying a protective member onto the second conductor;
• etching a portion of the second conductor other than a region in which the protective member is applied and a region therebelow;
• forming a third insulator on the second conductor;
• and
• forming a pillar including an oxide semiconductor in a region from which the sacrificial member has been removed, wherein
• the third conductor contacts a side surface of the pillar,
• the second conductor extends in a first direction, and contacts, on a side opposite to the pillar, the third conductor, and
• the third conductor is of a material with a higher work function than a material of the second conductor.

A semiconductor device, comprising:

• a first conductor;
• a first oxide semiconductor contacting, at one end, the first conductor, and extending in a first direction intersecting a surface of the first conductor;
• a first insulator surrounding a side surface of the first oxide semiconductor;
• a second conductor extending in a second direction intersecting the first direction, the second conductor and the first oxide semiconductor interposing the first insulator therebetween;
• a second oxide semiconductor contacting another end of the first oxide semiconductor;
• and
• a third conductor on the second oxide semiconductor, wherein
• the second oxide semiconductor has a larger area than the first oxide semiconductor in a top view.