Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
123 words
In a method for forming CMOS transistors and NPN transistors on a single wafer, said method including the step of forming an N well as the collector of an NPN vertical transistor, an improvement for forming at least one isolated, vertical PNP transistor comprising the steps of: forming an N-well to contain said PNP transistor during said step of forming an NPN vertical transistor collector; implanting N type material to form an N base of said PNP transistor; implanting a P type material at an energy greater than 300 keV for singly ionized material or greater than 150 kV for doubly ionized material to form a collector of said PNP transistor; and forming a P region as an emitter of said PNP transistor.
Claim 2
Dependent Claim
123 words
In a method for forming CMOS transistors and NPN transistors on a single wafer, said method including the step of forming an N well as the collector of an NPN vertical transistor, an improvement for forming at least one isolated, vertical PNP transistor comprising the steps of: forming an N-well to contain said PNP transistor during said step of forming an NPN vertical transistor collector; implanting N type material to form an N base of said PNP transistor; implanting a P type material at an energy greater than 300 keV for singly ionized material or greater than 150 kV for doubly ionized material to form a collector of said PNP transistor; and forming a P region as an emitter of said PNP transistor.
Claim 3
Dependent Claim
24 words
The method of claim 1 wherein said N base is implanted at a dosage of between 3×10 13 and 1.5×10 14 /cm 2 .
Claim 4
Dependent Claim
16 words
The method of claim 2 wherein said N type material for said N base is phosphorus.
Claim 5
Dependent Claim
14 words
The method of claim 1 wherein said N base is formed before said collector.
Claim 6
Dependent Claim
18 words
The method of claim 1 wherein said emitter is a shallow P+ region less than 0.35 um thick.
Claim 7
Dependent Claim
12 words
The method of claim 1 wherein said doubly ionized material is Boron.
Claim 8
Dependent Claim
28 words
The method of claim 1 wherein said PNP emitter is formed in the same step as a formation of a P+ source and drain for said CMOS transistors.
Claim 9
Dependent Claim
23 words
The method of claim 1 wherein said PNP collector is formed in the same step as the P base of said NPN transistors.
Claim 10
Dependent Claim
136 words
In a method for forming CMOS transistors and NPN transistors on a single wafer, said method including the step of forming an N-well as the collector of an NPN vertical transistor, an improvement for forming at least one isolated, vertical PNP transistor comprising the steps of: forming an N-well to contain said PNP transistor during said step of forming an NPN vertical transistor collector; implanting phosphorus at a dosage of between 3×10 13 and 1.5×10 14 /cm 2 to form an N base of said PNP transistor; implanting, after said N base implantation, doubly ionized Boron, at an energy of at least 300 KeV to form a collector of said PNP transistor; and forming a P+ region as an emitter of said PNP transistor simultaneously with forming P+ source and drain regions for said CMOS transistors.
Claim 11
Dependent Claim
136 words
In a method for forming CMOS transistors and NPN transistors on a single wafer, said method including the step of forming an N-well as the collector of an NPN vertical transistor, an improvement for forming at least one isolated, vertical PNP transistor comprising the steps of: forming an N-well to contain said PNP transistor during said step of forming an NPN vertical transistor collector; implanting phosphorus at a dosage of between 3×10 13 and 1.5×10 14 /cm 2 to form an N base of said PNP transistor; implanting, after said N base implantation, doubly ionized Boron, at an energy of at least 300 KeV to form a collector of said PNP transistor; and forming a P+ region as an emitter of said PNP transistor simultaneously with forming P+ source and drain regions for said CMOS transistors.
Claim 12
Dependent Claim
25 words
The method of claim 9 further comprising the steps of: implanting an N+ buried layer below said N-wells; and growing a P type epitaxial layer.