Method and apparatus for radiation hardened isolation
AssigneeHarris Corporation
InventorRobert T. Fuller
Life of this patent
Estimating the term…
Abstract
A radiation hardening isolation technique uses a poly buffered LOCOS structure (34, 36) to protect the device areas during field oxide 40 formation. The field oxide 40 is removed, and the polysilicon structure 34 is covered with a PSG or BPSG layer 42. Layer 42 is planarized and the polysilicon 34 is removed to provide a self-aligned device region 31.
Claims10
A method for fabricating a radiation hardened integrated circuits and isolating one radiation hardened device from other radiation hardened devices comprising the steps of:
- depositing a layer of polysilicon over a semiconductor substrate;
- patterning the layer of polysilicon to cover a device areas;
- covering the polysilicon layer with a layer of radiation hardening dielectric;
- planarizing the polysilicon and the radiation hardening dielectric to a common level;
- removing the polysilicon to expose device areas self-aligned to the radiation hardening dielectric;
- and
- forming semiconductor devices in the exposed device areas.
A method for fabricating a radiation hardened semiconductor device and isolating one radiation hardened device from other radiation hardened devices comprising the steps of:
- depositing a layer of polysilicon over a semiconductor substrate;
- covering the polysilicon layer with a first masking layer;
- patterning the first masking layer to cover a device areas;
- locally oxidizing the exposed substrate to form a field oxide between adjacent device areas;
- removing the first masking layer over the polysilicon;
- selectively removing the field oxide to expose the substrate outside the device areas;
- covering the substrate with a layer of radiation hardening dielectric;
- planarizing the polysilicon and the radiation hardening dielectric to a common level;
- removing the polysilicon to expose device areas self-aligned to the radiation hardening dielectric;
- and
- forming semiconductor devices in the exposed device areas.
Dependencies are inferred from the claim text.