Thin film silicon on insulator semiconductor integrated circuit with electrostatic damage protection and method

A method of protecting integrated circuits formed in thin film silicon on insulator substrates from electrostatic damage, comprising:

• forming a surface silicon controlled rectifier in a thin silicon device layer, the surface silicon controlled rectifier comprising:
• a first transistor having a control electrode, a first current carrying electrode, and a second current carrying electrode, the control electrode of the first transistor coupled to the first current carrying electrode of the first transistor;
• and
• a second transistor having a control electrode, a first current carrying electrode, and a second current carrying electrode, the control electrode of the second transistor coupled to the first current carrying electrode of the second transistor, the second current carrying electrode of the second transistor coupled to the control electrode of the first transistor and the second current carrying electrode of the first transistor coupled to the control electrode of the second transistor;
• forming a low voltage triggering apparatus in said thin silicon device layer;
• electrically coupling said low voltage triggering apparatus to said surface silicon controlled rectifier to form an electrostatic damage protection device;
• and
• electrically coupling said electrostatic damage protection device to an input/output circuit.

A method of forming a low voltage triggered silicon controlled rectifier on a thin film silicon on insulator substrate comprising the steps of:

• forming a first transistor having a base, an emitter and a collector in a thin silicon device layer;
• forming a second transistor having a base, an emitter and a collector in said thin silicon device layer, wherein said collector of said first transistor is electrically coupled to said base of said second transistor and wherein said collector of said second transistor is electrically coupled to said base of said first transistor;
• and
• forming a low voltage triggering apparatus wherein said low voltage triggering apparatus is electrically coupled to said base of said first transistor and said base of said second transistor, and wherein said low voltage triggering apparatus is self-triggering at a predictable current.