Methods of simultaneous contact and metal lithography patterning

A lithographic method in which both positive and reversal image processes are sequentially carried out in a single layer of photoresist comprising the steps of:

• applying, drying, exposing and developing a selected region of positive photoresist containing a basic material deposited on the surface of a body to provide a positive image defining a contact area on said surface,
• re-exposing the remaining photoresist with a negative mask defining a selected zone which includes the previously defined contact area,
• baking for a period of time to decarboxylate the decomposition products formed in the photoresist in the re-exposed zone, thus fixing the negative image in the photoresist,
• blanket exposing the entire body to render alkali soluble the remaining photoresist which has not previously been exposed, and
• developing, in a weak alkaline developer to remove said alkali soluble photoresist from the surface of the body leaving the re-exposed, baked decarboxylated photoresist on said surface.

A photolithographic method of processing a semiconductor in which both positive and reversal image processes are sequentially carried out in a single layer of positive photoresist containing a basic material comprising the steps of:

• applying, drying, exposing and developing selected regions of a photoresist on the oxide coated surface of a semiconductor body to provide a positive image defining contact via areas in said oxide coating,
• etching said vias while protecting the unexposed remaining photoresist from exposure,
• re-exposing the remaining photoresist with a negative mask defining contact metallurgy in zones which include the previously defined vias,
• baking for a period of time to decarboxylate the decomposition products formed in the photoresist in the re-exposed zones, thus fixing the negative image in the photoresist,
• blanket exposing the entire body to render alkali soluble the remaining photoresist which have not previously been exposed,
• developing, in a weak alkaline developer to remove said alkali soluble photoresist the re-exposed, baked, decarboxylated photoresist in all areas where metallurgy is not wanted, and
• depositing metal on the semiconductor and removing the remaining re-exposed, baked, photoresist and any overlying metal.

A lithographic method in which both positive and reversal image processes are sequentially carried out in a single layer of positive photoresist containing a basic material comprising the steps of:

• applying, drying and exposing selected portions of the photoresist deposited on the surface of a body, to form a negative image defining a contact area to be created on the surface,
• baking for a period of time to decarboxylate the decomposition products of the photoresist in the exposed area, thus fixing the negative image in the photoresist,
• exposing a contact zone within the defined contact area by exposing the area through a positive mask and developing said zone to expose selected regions on the surface of the body,
• blanket exposing the entire body to render alkali soluble all previously unexposed photoresist,
• treating the body with a week alkaline developer to remove the alkali soluble photoresist leaving the baked photoresist on said surface, and
• removing the remaining baked photoresist.

A photolithograhic method of processing a photoresist in which both positive and reversal image processes are sequentially carried out in a single layer of positive photoresist containing a basic material comprising the steps of:

• applying, drying and exposing selected portions of the photoresist on the oxide coated surface of a semiconductor body, through a negative mask defining contact areas to be created on the body,
• baking for a period of time to decarboxylate the decomposition products of the photoresist in the exposed areas, thus fixing the negative image in the photoresist,
• exposing contact zones within the defined contact areas by exposing the defined contact areas through a positive mask, and developing said zones to expose selected regions on the oxide coated surface,
• etching vias through said oxide in said regions while protecting the unexposed remaining photoresist from exposure,
• blanket exposing the entire body to render alkali soluble all previously unexposed photoresist,
• treating the body with a weak alkaline developer to remove the alkali soluble photoresist leaving the baked photoresist on said surface in all areas where metallurgy is not wanted,
• depositing metal on said body and removing the remaining baked photoresist and any overlying metal.