EP0322050A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Electronic device manufacture with deposition of material, particularly cadmium mercury telluride
Assignee: Philips Electronics UK Ltd
•
Filing: 1988-12-16
•
Granted: —
•
Expires: 2008-12-16
Abstract
Abstract In the manufacture of an electronic device, e.g. an infrared detector of cadmium mercury telluride, a gas stream (36) comprising two or more reactants is passed over a heated substrate (29) in a reaction zone (C) of a reactor vessel (1) so as to deposit material in a layer (30) on the substrate (29). One reactant, e.g. a readily decomposible cadmium alkyl (Me₂Cd), is supplied to the reaction zone (C) by means of an injection tube (12) which passes through a heated first zone (A) of the vessel (1). The tube (12) has a narrow bore (y) to provide a high flow velocity for this reactant (Me₂Cd) through the first zone (A). In accordance with the invention, the tube (12) widens in at least one dimension (x), towards its outlet end, so as to provide a wider outlet for injecting the reactant (Me₂Cd) into the gas stream (38,36) with a lower flow velocity which matches more closely the flow velocity of the gas stream (38,36). A more balanced mixing is achieved leading to improved compositional homogeneity in the deposited layer (30), even for difficult materials such as cadmium mercury telluride. The heated first zone (A) may comprise a capsule (2) containing e.g. a pool of mercury (3), and such a capsule (2) preferably has an outlet (a) of smaller cross-sectional area within which the widened outlet of the injection tube (12) is concentrically arranged so that the gas stream (38) is symmetrically constricted around the outlet of the injection tube (12).
Inventors
- 👤 Peter Arthur Charles Whiffin
- 👤 Christopher David Maxey
- 👤 Brian Colin Easton
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 21:02
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/44; C23C16/455; C23C16/45561; C30; C30B; C30B25/00; C30B25/02; C30B25/14; C30B29/00; C30B29/10; C30B29/46; C30B29/48; H; H10; H10P; H10P14/00; H10P14/20; H10P14/24; H10P14/34; H10P14/3402; H10P14/3424; H10P14/3432; H10P14/3438; H10P14/3441
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
186 words
In a method of manufacturing an electronic device, a gas stream comprising at least first and second reactants is passed over a heated substrate in a reaction zone of a reactor vessel so as to deposit material in a layer on the substrate, the first reactant being supplied to the reaction zone separately from the second reactant by means of an injection tube which passes in the reactor vessel through a heated first zone of the vessel so as to inject the first reactant into the gas stream at a location between the first zone and the substrate, the tube having a narrow bore to provide a high flow velocity for the first reactant through the first zone, characterised in that the tube has said narrow bore over most of its length in the first zone and then, towards its outlet end, the tube widens in at least one dimension so as to provide an unobstructed wider outlet for injecting the first reactant into the gas stream with a lower flow velocity which matches more closely the flow velocity of the gas stream at said location.
Claim 2
Dependent Claim
186 words
In a method of manufacturing an electronic device, a gas stream comprising at least first and second reactants is passed over a heated substrate in a reaction zone of a reactor vessel so as to deposit material in a layer on the substrate, the first reactant being supplied to the reaction zone separately from the second reactant by means of an injection tube which passes in the reactor vessel through a heated first zone of the vessel so as to inject the first reactant into the gas stream at a location between the first zone and the substrate, the tube having a narrow bore to provide a high flow velocity for the first reactant through the first zone, characterised in that the tube has said narrow bore over most of its length in the first zone and then, towards its outlet end, the tube widens in at least one dimension so as to provide an unobstructed wider outlet for injecting the first reactant into the gas stream with a lower flow velocity which matches more closely the flow velocity of the gas stream at said location.
Claim 3
Dependent Claim
230 words
In a method of manufacturing an electronic device comprising cadmium mercury telluride, a mercury source is heated in a first zone of a reactor vessel to maintain an atmosphere of mercury vapour in a second, reaction zone of the reactor vessel, and a gas stream comprising a volatile tellurium compound and a volatile cadmium compound is passed over a heated substrate in the reaction zone in the presence of the mercury vapour so as to deposit material for a layer of cadmium mercury telluride on the substrate, the volatile cadmium compound being supplied to the reaction zone separately from the volatile tellurium compound by means of an injection tube which passes in the reactor vessel through the first zone so as to inject the volatile cadmium compound into the gas stream at a location between the mercury source and the substrate, the tube having a narrow bore to provide a high flow velocity for the cadmium compound through the first zone, characterised in that the tube has said narrow bore over most of its length in the first zone and then, towards its outlet end, the tube widens in at least one dimension so as to provide an unobstructed wider outlet for injecting the volatile cadmium compound into the gas stream with a lower flow velocity which matches more closely the flow velocity of the gas stream at said location.
Claim 4
Dependent Claim
230 words
In a method of manufacturing an electronic device comprising cadmium mercury telluride, a mercury source is heated in a first zone of a reactor vessel to maintain an atmosphere of mercury vapour in a second, reaction zone of the reactor vessel, and a gas stream comprising a volatile tellurium compound and a volatile cadmium compound is passed over a heated substrate in the reaction zone in the presence of the mercury vapour so as to deposit material for a layer of cadmium mercury telluride on the substrate, the volatile cadmium compound being supplied to the reaction zone separately from the volatile tellurium compound by means of an injection tube which passes in the reactor vessel through the first zone so as to inject the volatile cadmium compound into the gas stream at a location between the mercury source and the substrate, the tube having a narrow bore to provide a high flow velocity for the cadmium compound through the first zone, characterised in that the tube has said narrow bore over most of its length in the first zone and then, towards its outlet end, the tube widens in at least one dimension so as to provide an unobstructed wider outlet for injecting the volatile cadmium compound into the gas stream with a lower flow velocity which matches more closely the flow velocity of the gas stream at said location.
Claim 5
Dependent Claim
69 words
A method as claimed in claim 1, further characterised in that in the first zone the gas stream flows through a capsule containing a source of a reactant, and that the cross-section of the capsule narrows towards at least one end to provide the capsule with an outlet of smaller cross-sectional area, and that the outlet of the injection tube is concentrically arranged within the outlet of the capsule.
Claim 6
Dependent Claim
68 words
A method as claimed in claim 2, further characterised in that in the first zone the gas stream flows through a capsule containing a pool of mercury, and that the cross-section of the capsule narrows towards at least one end to provide the capsule with an outlet of smaller cross-sectional area, and that the outlet of the injection tube is concentrically arranged within the outlet of the capsule.
Claim 7
Dependent Claim
53 words
A method as claimed in claim 3 or claim 4, further characterised in that a mixing zone is present between the capsule and the reaction zone, and the mixing zone has a larger cross-sectional area than that of the outlet of the capsule and than that of the reaction zone over the substrate.
Claim 8
Independent Claim
51 words
A method as claimed in anyone of the preceding claims, further characterised in that the gas stream flows through the reaction zone between a lower major surface formed by a heated susceptor having the substrate thereon and an upper major surface formed by a flat upper wall of the reactor vessel.
Claim 9
Dependent Claim
33 words
A method as claimed in claim 6, further characterised in that said at least one dimension in which the tube widens is substantially parallel to the flat upper wall of the reactor vessel.
Claim 10
Independent Claim
48 words
A method as claimed in anyone of the preceding claims, further characterised in that the wider outlet is spaced from the heated substrate by a distance along the reactor vessel, which distance is at least 2 times the average cross-sectional dimension of the reactor vessel at that location.
Claim 11
Independent Claim
31 words
A method as claimed in anyone of the preceding claims, further characterised in that a dopant for the layer is supplied to the reaction zone by means of the injection tube.
Claim 12
Dependent Claim
198 words
A reactor vessel for use in a method claimed in anyone of the preceding claims, having a reaction zone preceded by a first zone, support means for supporting a substrate in the reaction zone, heating means for heating the first zone and the reaction zone, respective first and second supply means for supplying a first reactant and a second reactant in a gas stream to the reaction zone, the first supply means comprising an injection tube which passes in the reactor vessel through the first zone of the vessel so as to inject the first reactant into the gas stream at a location between the first zone and the substrate, the tube having a narrow bore to provide a high flow velocity for the first reactant through the first zone, characterised in that the tube has said narrow bore over most of its length in the first zone and then, towards its outlet end, the tube widens in at least one dimension so as to provide an unobstructed wider outlet for injecting the first reactant into the gas stream with a lower flow velocity which matches more closely the flow velocity of the gas stream at said location.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.