Plasma doping process and apparatus therefor
First Claim
Patent Images
1. Method for plasma-doping of impurity on a semiconductor substrate comprising the steps of:
- placing an object semiconductor substrate on a first electrode in a vacuum chamber,introducing a gas of a controlled reduced pressure containing at least one impurity, into said vacuum chamber,impressing a radio frequency current of a high voltage in intermittence across said first electrode and a second electrode in said chamber thereby causing radio frequency discharging in said chamber, to generate plasma doping, andcontrolling a duty ratio of said intermittence in accordance with a program to control the amount of impurity doped on a surface of said substrate.
1 Assignment
0 Petitions
Accused Products
Abstract
In a plasma doping process utilizing a radio frequency discharging in a vacuum by for doping an impurity into a semiconductor substrate, the radio frequency discharging is made intermittently and under controlling of average current of the discharging, thereby the impurity concentration is desirably controlled; and especially by selecting the vacuum in a range between 1×10-4 -5×10-2 torr, undesirable deposition of the impurity on the substrate surface is evadable.
162 Citations
14 Claims
-
1. Method for plasma-doping of impurity on a semiconductor substrate comprising the steps of:
-
placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a controlled reduced pressure containing at least one impurity, into said vacuum chamber, impressing a radio frequency current of a high voltage in intermittence across said first electrode and a second electrode in said chamber thereby causing radio frequency discharging in said chamber, to generate plasma doping, and controlling a duty ratio of said intermittence in accordance with a program to control the amount of impurity doped on a surface of said substrate. - View Dependent Claims (3, 4)
-
-
2. Method for plasma-doping of impurity on a semiconductor substrate comprising the step of:
-
placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a controlled reduced pressure containing at least one impurity into said vacuum chamber, and impressing a radio frequency current of a high voltage in intermittence across said first electrode and said second electrode in said chamber, the frequency of said intermittence being 0.1 Hz to 50 Hz, thereby causing radio frequency discharging in said chamber to generate a plasma doping.
-
-
5. Method for plasma-doping of impurity on a semiconductor substrate comprising the steps of:
-
placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a controlled reduced pressure containing at least one impurity, into said vacuum chamber, impressing a radio frequency current of a high voltage across said first electrode and a second electrode in said chamber through means for measuring said radio frequency current, thereby causing radio frequency discharging in said chamber to generate a plasma, and controlling said radio frequency current based on a measurement thereof in accordance with a program, to control amount of impurity doped on the surface of said substrate. - View Dependent Claims (6, 7)
-
-
8. Method for plasma doping of impurity of a semiconductor substrate comprising the steps of:
-
placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a pressure of from 1×
10-3 torr to 5×
10-2 torr containing at least one impurity, into said vacuum chamber,intermittently impressing a radio frequency current of a high voltage across said first electrode and a second electrode in said chamber, and controlling the impressed period of said current to contol the amount of impurity doped on a surface of said substrate. - View Dependent Claims (9)
-
-
10. Method for plasma-doping of impurity on a semiconductor substrate comprising the steps of:
-
placing an object semiconductor substrate on a first electrode in a vacuum chamber, introducing a gas of a pressure of from 1×
10-4 torr to 5×
10-2 torr containing at least one impurity, into said vacuum chamber,intermittently impressing a radio frequency current of a high voltage across said first electrode and a second electrode in said chamber and microwave into said chamber thereby causing radio frequency discharging and electronic cyclotron resonance discharge in said chamber, to generate plasma doping, and controlling the impressed period of said current to control the amount of impurity doped on a surface of said substrate. - View Dependent Claims (11, 12, 13)
-
-
14. Method for plasma-doping of impurity on a semiconductor substrate comprising the steps of:
-
placing an object semiconductor substrate on a first electrode in a vacuum chamber. introducing a gas of a controlled reduced pressure containing at least one impurity, into said vacuum chamber, and impressing a radio frequency current of a high voltage in intermittence across said first electrode and a second electrode in said chamber thereby causing radio the frequency discharging in said chamber, frequency of said intermittence being changed to make plasma doping with depthwise modulated concentration in said semiconductor substrate.
-
Specification