Abstract Disclosed herein is a method of manufacturing a lateral transistor, in which a semiconductor crystal comprising two layers, namely, a first layer and a second layer formed so that said first layer contains two conductivity types of impurities, that is, first and second impurities which are opposite to and the same as a conductivity type of impurities contained in the second layer, respectively, said second impurities being lower in concentration and greater in diffusion constant than the first impurities; a part of the semiconductor crystal being selectively etched until the second layer is exposed; a region which has the same conductivity type as the first layer and which is small in impurity concentration being formed by the epitaxial growth method in the thus etched part; then a main base region being formed by diffusing of the second impurities into the thus formed region, whereby various advantages such as alleviation of the Early effect, avoidance of punch-through, a high accuracy in control of a base width and reduction of a base resistance are obtained.
A METHOD OF MANUFACTURING A LATERAL TRANSISTOR WHICHL COMPRISES THE STEPS OF, FORMING AS A LAYER ON A SUBSTRATE OF SEMICONDUCTOR MATERIAL WHICH CONTAINS AN IMPURITY OF A FIRST CONDUCTIVITY TYPE, A FIRST REGION CONTAINING AN IMPURITY HAVING A HIGH DIFFUSION CHARACTERISTIC OF THE SAME TYPE AS SAID SUBSTRATE AND AN IMPURITY OF THE OPPOSITE CONDUCTIVITY TYPE HAVING A HIGH CONCENTRATION AND LOW DIFFUSION CHARACTERISTIC, PROVIDING A MASK OVER SAID FIRST REGION, PROVIDING A WINDOW IN SAID MASK, FORMING THROUGH SAID FIRST REGION A RECESS TO EXPOSE SAID SUBSTRATE THROUGH SAID WINDOW, SUCCESSIVELY DEPOSITING IN SAID RECESS BY EPITAXIAL GROWTH THROUGH SAID WINDOW LIGHTLY DOPED SECOND AND HEAVILY DOPED THIRD REGIONS OF SEMICONDUCTOR MATERIAL OF SAID OPPOSITE CONDUCTIVITY TYPE, SAID THIRD REGION BEING ISOLATED FROM SAID FIRST REGION BY SAID SECOND REGION, EFFECTING BY HEAT DIFFUSION A DIFFUSION OF IMPURITITY OF SAID FIRST CONDUCTIVITY TYPE FROM SAID REGION INTO SAID SECOND REGION TO FORM BETWEEN SAID FIRST AND SECOND REGIONS A BASE REGION THE WIDTH OF WHICH IS DETERMINED BY THE DIFFERENCE IN DIFFUSION OF SAID IMPURITIES OF SAID CONDUCTIVITY TYPE AND SAID SECOND CONDUCTIVITY TYPE, AND FORMING ELECTRICAL CONTACT WITH SAID FIRST, THIRD AND BASE REGIONS, RESPECTIVELY.
Claim 2
Independent Claim
198 words
A METHOD OF MANUFACTURING A LATERAL TRANSISTOR WHICHL COMPRISES THE STEPS OF, FORMING AS A LAYER ON A SUBSTRATE OF SEMICONDUCTOR MATERIAL WHICH CONTAINS AN IMPURITY OF A FIRST CONDUCTIVITY TYPE, A FIRST REGION CONTAINING AN IMPURITY HAVING A HIGH DIFFUSION CHARACTERISTIC OF THE SAME TYPE AS SAID SUBSTRATE AND AN IMPURITY OF THE OPPOSITE CONDUCTIVITY TYPE HAVING A HIGH CONCENTRATION AND LOW DIFFUSION CHARACTERISTIC, PROVIDING A MASK OVER SAID FIRST REGION, PROVIDING A WINDOW IN SAID MASK, FORMING THROUGH SAID FIRST REGION A RECESS TO EXPOSE SAID SUBSTRATE THROUGH SAID WINDOW, SUCCESSIVELY DEPOSITING IN SAID RECESS BY EPITAXIAL GROWTH THROUGH SAID WINDOW LIGHTLY DOPED SECOND AND HEAVILY DOPED THIRD REGIONS OF SEMICONDUCTOR MATERIAL OF SAID OPPOSITE CONDUCTIVITY TYPE, SAID THIRD REGION BEING ISOLATED FROM SAID FIRST REGION BY SAID SECOND REGION, EFFECTING BY HEAT DIFFUSION A DIFFUSION OF IMPURITITY OF SAID FIRST CONDUCTIVITY TYPE FROM SAID REGION INTO SAID SECOND REGION TO FORM BETWEEN SAID FIRST AND SECOND REGIONS A BASE REGION THE WIDTH OF WHICH IS DETERMINED BY THE DIFFERENCE IN DIFFUSION OF SAID IMPURITIES OF SAID CONDUCTIVITY TYPE AND SAID SECOND CONDUCTIVITY TYPE, AND FORMING ELECTRICAL CONTACT WITH SAID FIRST, THIRD AND BASE REGIONS, RESPECTIVELY.