Mixed crystal layer growing method and device, and semiconductor device
AssigneeFujitsu Limited
InventorsTakae Sukegawa, Hidekazu Sato
Life of this patent
Estimating the term…
Abstract
When a silicon-germanium mixed crystal layer is grown on a substrate by introducing a silicon source gas, a germanium source gas, a boron source gas, and a carbon source gas into a reaction chamber, the flow rate of the carbon source gas is set at 5 sccm or higher and the supply concentration of the carbon source gas is set as low as approximately 1.0% under the condition that the silicon-germanium mixed crystal layer is doped with carbon with a concentration of approximately 0.5%; resulting in, carbon with a concentration required to inhibit the diffusion of boron is doped into the layer and the concentration of carbon becomes equal to or higher than the concentration of boron in a region at any given depth.
Claims13
A mixed crystal layer growing method comprising the steps of:
- introducing source gases into the reaction chamber;
- and
- growing a silicon-germanium mixed crystal layer on a substrate placed in a reaction chamber,
- wherein the source gases include a silicon source gas, a germanium source gas, a first impurity source gas, and a second impurity source gas for inhibiting the diffusion or a first impurity in the mixed crystal layer, and the concentration of a second impurity is equal to or higher than the concentration of the first impurity in a region at any given depth of the silicon-germanium mixed crystal layer;
- wherein
- a supply timing from a supply source of the second impurity source gas is earlier than a supply timing from a supply source of the first impurity source gas, and a timing of stopping the supply from the supply source of the second impurity source gas is later than a timing of stopping the supply from the supply source of the first impurity source gas;
- and
- the timing of stopping the supply from the supply source of the first impurity source gas is the same as a timing of stopping a supply of the germanium source gas.
A mixed crystal layer growing method comprising the steps of:
- introducing source gases into the reaction chamber;
- and
- growing a silicon-germanium mixed crystal layer on a substrate placed in a reaction chamber,
- wherein the source gases include a silicon source gas, a germanium source gas, a first impurity source gas, and a second impurity source gas for inhibiting the diffusion of a first impurity in the mixed crystal layer, and the concentration of a second impurity is equal to or higher than the concentration of the first impurity in a region at any given depth of the silicon-germanium mixed crystal layer;
- wherein
- a supply timing from a supply source of the second impurity source gas is earlier than a supply timing from a supply source of the first impurity source gas, and a timing of stopping a supply from a supply source of the second impurity source gas is later than a timing of stopping a supply from a supply source of the first impurity source gas, wherein
- the occurrence of a difference in doping depth between the dopings of the first impurity source and the second impurity source into the silicon-germanium mixed crystal layer is prevented.
Dependencies are inferred from the claim text.